53 results on '"Katherine Langford"'
Search Results
2. Oxidative stress in the algae Chlamydomonas reinhardtii exposed to biocides
- Author
-
Katherine Langford, Knut Erik Tollefsen, Ana Catarina Almeida, Tânia Gomes, and Kevin V. Thomas
- Subjects
Chlorophyll ,0301 basic medicine ,Health, Toxicology and Mutagenesis ,Chlamydomonas reinhardtii ,010501 environmental sciences ,Aquatic Science ,Photosynthesis ,Photochemistry ,medicine.disease_cause ,01 natural sciences ,Electron Transport ,Lipid peroxidation ,03 medical and health sciences ,chemistry.chemical_compound ,medicine ,Carotenoid ,0105 earth and related environmental sciences ,Photosystem ,chemistry.chemical_classification ,Reactive oxygen species ,Dose-Response Relationship, Drug ,biology ,Photosystem II Protein Complex ,Glutathione ,biology.organism_classification ,Carotenoids ,High-Throughput Screening Assays ,Oxidative Stress ,030104 developmental biology ,chemistry ,Biochemistry ,Lipid Peroxidation ,Reactive Oxygen Species ,Oxidation-Reduction ,Water Pollutants, Chemical ,Oxidative stress ,Disinfectants ,Environmental Monitoring - Abstract
The toxicity of biocides can be associated with the formation of reactive oxygen species (ROS) and subsequent oxidative damage, interfering with the normal function of photosynthetic organisms. This study investigated the formation and effects of ROS in the unicellular green algae Chlamydomonas reinhardtii exposed to three environmentally relevant biocides, aclonifen, dichlofluanid and triclosan. After a first screening to identify which biocides induced ROS, a 24h multi-endpoint analysis was used to verify the possible consequences. A battery of high-throughput methods was applied in algae for measuring ROS formation, reduced glutathione (GSH), lipid peroxidation (LPO), photosystem (PS) II performance and pigments (chlorophylls a, b and carotenoids). Results show that only aclonifen induced ROS after the first 6h exposure, with the other two biocides not showing any ROS formation. Aclonifen, a Protox and carotenoid inhibitor, induced a concentration-dependent ROS formation, LPO and interfered with algae pigments content, while no alterations were detected in GSH content. A significant effect was also seen in the photosynthetic process, especially a reduction in the maximum and effective quantum yields, accompanied by alterations in energy dissipation in PSII reaction centers and the impairment of the electron transport rate. This study demonstrated the successful use of a battery of high-throughput methods for quickly screening biocides capacity to induce the formation of ROS and the subsequent effects in C. reinhardtii, thus revealing their mode of action (MoA) at concentrations before an impact on growth can become effective.
- Published
- 2017
- Full Text
- View/download PDF
3. Tralopyril bioconcentration and effects on the gill proteome of the Mediterranean mussel Mytilus galloprovincialis
- Author
-
Ksenia J. Groh, René Schönenberger, Julita Stadnicka-Michalak, Carlos M. Barroso, Isabel Oliveira, Katherine Langford, Ricardo Beiras, Kevin V. Thomas, and Marc J.-F. Suter
- Subjects
Gills ,Male ,Proteomics ,0301 basic medicine ,Gill ,Mediterranean mussel ,animal structures ,Proteome ,Bioenergetics ,Health, Toxicology and Mutagenesis ,Bioconcentration ,010501 environmental sciences ,Aquatic Science ,Biology ,01 natural sciences ,03 medical and health sciences ,Toxicity Tests, Acute ,Animals ,Pyrroles ,Toxicity Tests, Chronic ,0105 earth and related environmental sciences ,Mytilus ,Mussel ,biology.organism_classification ,Oxidative Stress ,030104 developmental biology ,Biochemistry ,Environmental chemistry ,Inactivation, Metabolic ,Toxicity ,Female ,Biomarkers ,Water Pollutants, Chemical ,Disinfectants - Abstract
Antifouling (AF) systems are used worldwide as one of the most cost-effective ways of protecting submerged structures against heavy biofouling. The emergence of environmentally friendly AF biocides requires knowledge on their environmental fate and toxicity. In this study we measured the bioconcentration of the emerging AF biocide tralopyril (TP) in the Mediterranean mussel Mytilus galloprovincialis and investigated the effects of TP on the mussel gill proteome following acute (2days) and chronic (30days) exposure, as well as after a 10-day depuration period. The experiments were carried out with 1μg/L TP; blank and solvent (5×10(-5)% DMSO) controls were also included. Proteomics analysis was performed by mass spectrometry-based multidimensional protein identification technology (MudPIT). Differentially expressed proteins were identified using a label-free approach based on spectral counts and G-test. Our results show that TP is rapidly accumulated by mussels at concentrations up to 362ng/g dw (whole tissues), reaching steady-state condition within 13days. Ten days of depuration resulted in 80% elimination of accumulated TP from the organism, suggesting that a complete elimination could be reached with longer depuration times. In total, 46 proteins were found to be regulated in the different exposure scenarios. Interestingly, not only TP but also DMSO alone significantly modulated the protein expression in mussel gills following acute and chronic exposure. Both compounds regulated proteins involved in bioenergetics, immune system, active efflux and oxidative stress, often in the opposite way. Alterations of several proteins, notably several cytoskeletal ones, were still observed after the depuration period. These may reflect either the continuing chemical effect due to incomplete elimination or an onset of recovery processes in the mussel gills. Our study shows that exposure of adult mussels to sublethal TP concentration results in the bioconcentration of this biocide in the tissues and modulates the expression of several proteins that may intervene in important metabolic pathways.
- Published
- 2016
- Full Text
- View/download PDF
4. Oxidative stress potential of the herbicides bifenox and metribuzin in the microalgae Chlamydomonas reinhardtii
- Author
-
Katherine Langford, Ana Catarina Almeida, Kevin V. Thomas, Tânia Gomes, and Knut Erik Tollefsen
- Subjects
Photosystem II ,Health, Toxicology and Mutagenesis ,Chlamydomonas reinhardtii ,Context (language use) ,010501 environmental sciences ,Aquatic Science ,Photosynthesis ,medicine.disease_cause ,01 natural sciences ,Lipid peroxidation ,03 medical and health sciences ,chemistry.chemical_compound ,Eco-toxicology: 489 [VDP] ,Metribuzin ,medicine ,Økotoksikologi: 489 [VDP] ,Microalgae ,030304 developmental biology ,0105 earth and related environmental sciences ,0303 health sciences ,Bifenox ,biology ,Herbicides ,Triazines ,Phenyl Ethers ,Photosystem II Protein Complex ,biology.organism_classification ,Oxidative Stress ,chemistry ,Biochemistry ,13. Climate action ,Lipid Peroxidation ,Reactive Oxygen Species ,Oxidative stress ,Water Pollutants, Chemical - Abstract
The widespread presence of herbicides in the aquatic environment has raised awareness about the need to develop further in depth ecotoxicological risk assessments, more specifically on potential effects on photosynthetic organisms as microalgae. The majority of the information available regarding the toxicity of herbicides towards microalgae is related to traditional toxicological and regulatory-relevant endpoints such as growth inhibition, leaving a significant gap on knowledge regarding underlying interactions and damage to biological targets. In this context, this study aimed to supplement the general toxicity information of bifenox and metribuzin in the microalgae Chlamydomonas reinhardtii using a battery of selected high-throughput methods. This multiple-endpoint approach included the measurement of formation of reactive oxygen species (ROS), alterations in reduced glutathione (GSH) content, formation of lipid peroxidation (LPO), photosystem II (PSII) performance and loss of photosynthetic pigments after 24 h exposure. Results obtained showed that both herbicides caused a concentration-dependent increase in ROS formation, with bifenox showing higher but less reactive ROS. This increase in ROS production by bifenox and metribuzin was followed by alterations in the antioxidant capacity of algae, oxidative damage in the form of LPO and alterations in pigment content. Furthermore, both herbicides impacted the photosynthetic activity of algae, as seen by alterations in the maximum and effective quantum efficiency of PSII, PSII photochemistry and energy dissipation pathways, impact in the water-splitting apparatus and reduction in the electron transport rate. The inhibitory effect of metribuzin on photosynthetic processes/components was larger than that seen for bifenox. The impact of bifenox and metribuzin in the photosynthetic processes of C. reinhardtii seems to be in close association with the formation of ROS and consequent oxidative stress and damage in algal cells. Overall, this study showed that the high-throughput methods developed could successfully characterise both potential Modes of Action and adverse effects of bifenox and metribuzin in C. reinhardtii.
- Published
- 2019
5. Benzoylurea pesticides used as veterinary medicines in aquaculture: Risks and developmental effects on nontarget crustaceans
- Author
-
Katherine Langford, Ailbhe Macken, and Adam Lillicrap
- Subjects
business.industry ,Health, Toxicology and Mutagenesis ,Benzoylurea ,fungi ,Biology ,Pesticide ,biology.organism_classification ,Crustacean ,Acute toxicity ,Toxicology ,chemistry.chemical_compound ,Diflubenzuron ,chemistry ,Aquaculture ,Azamethiphos ,medicine ,Environmental Chemistry ,business ,Copepod ,medicine.drug - Abstract
Diflubenzuron and teflubenzuron are benzoylureas that are used in aquaculture to control sea lice. Flubenzurons have low toxicity to many marine species such as fish and algae but by their nature are likely to have significant adverse effects on nontarget species such as crustaceans and amphipods. Although the exact mechanism of toxicity is not known, these compounds are thought to inhibit the production of the enzyme chitin synthase during molting of immature stages of arthropods. These chitin synthesis inhibitors are effective against the larval and pre-adult life stages of sea lice. Due to their low solubility and results of recent monitoring studies conducted in Norway, the sediment compartment is considered the most likely reservoir for these compounds and possible remobilization from the sediment to benthic crustaceans could be of importance. For this reason, the epibenthic copepod Tisbe battagliai was selected for investigations into the acute and developmental effects of these compounds. For comparative purposes, azamethiphos was investigated to identify differences in sensitivity and act as a negative control for developmental effects at environmentally relevant concentrations. Standard acute studies with adult copepods showed little or no acute toxicity at milligrams per liter levels with the flubenzurons, whereas a naupliar developmental test demonstrated that environmentally relevant concentrations (e.g., nanograms per liter) caused a complete cessation of molting and finally death in the exposed copepods.
- Published
- 2015
- Full Text
- View/download PDF
6. Identification of algal growth inhibitors in treated waste water using effect-directed analysis based on non-target screening techniques
- Author
-
Peter Oswald, Ludek Blaha, Kevin V. Thomas, Klára Hilscherová, Jaroslav Slobodnik, Zuzana Toušová, Malcolm J. Reid, Jean Froment, Katherine Langford, and Knut Erik Tollefsen
- Subjects
Biocide ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Fractionation ,010501 environmental sciences ,Wastewater ,01 natural sciences ,chemistry.chemical_compound ,Microalgae ,Environmental Chemistry ,Atrazine ,Acetochlor ,Waste Management and Disposal ,Effluent ,0105 earth and related environmental sciences ,Czech Republic ,010401 analytical chemistry ,Pesticide ,Pollution ,6. Clean water ,Growth Inhibitors ,0104 chemical sciences ,chemistry ,13. Climate action ,Environmental chemistry ,Toxicity ,Phenothrin ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
Growth inhibition of freshwater microalga Pseudokirchneriella subcapitata caused by a waste water treatment plant (WWTP) effluent extract was investigated using an effect directed analysis (EDA) approach. The objective was to identify compounds responsible for the toxicity by combining state-of-the-art sampling, bioanalytical, fractionation and non-target screening techniques. Three fractionation steps of the whole extract were performed and bioactive fractions were analysed with GC (xGC)-MS and LC-HRMS. In total, 383 compounds were tentatively identified, and their toxicity was characterized using US EPA Ecotox database, open scientific literature or modelled by ECOSAR. Among the top-ranking drivers of toxicity were pesticides and their transformation products, pharmaceuticals (barbiturate derivatives and macrolide antibiotics e.g. azithromycin), industrial compounds or caffeine and its metabolites. Several of the top-ranking pesticides are no longer registered for use in plant protection products or biocides in the Czech Republic (e.g. prometryn, atrazine, acetochlor, resmethrin) and some are approved only for use in biocides (e.g. terbutryn, carbendazim, phenothrin), which indicates that their non-agricultural input into aquatic environment via WWTPs should be carefully considered. The study demonstrated a functional strategy of combining biotesting, fractionation and non-target screening techniques in the EDA study focused on the identification of algal growth inhibitors in WWTP effluent.
- Published
- 2018
7. Mixture toxicity of five biocides with dissimilar modes of action on the growth and photosystem II efficiency of Chlamydomonas reinhardtii
- Author
-
Kevin V. Thomas, Ana Catarina Almeida, Katherine Langford, Karina Petersen, and Knut Erik Tollefsen
- Subjects
0301 basic medicine ,Biocide ,Photosystem II ,Endpoint Determination ,Health, Toxicology and Mutagenesis ,Chlamydomonas reinhardtii ,010501 environmental sciences ,Biology ,Toxicology ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Metribuzin ,Botany ,Toxicity Tests ,Mode of action ,0105 earth and related environmental sciences ,Bifenox ,Aniline Compounds ,Herbicides ,Triazines ,Phenyl Ethers ,Photosystem II Protein Complex ,biology.organism_classification ,Triclosan ,030104 developmental biology ,chemistry ,Environmental chemistry ,Toxicity ,Growth inhibition ,Water Pollutants, Chemical ,Disinfectants - Abstract
Biocides are extensively used and universally distributed. Some are highly toxic to algae, including antifoulants, herbicides, and fungicides. The inhibition of algal growth is an important regulatory endpoint for toxicity assessment of single compounds. However, in the aquatic environment, mixtures of compounds with unknown toxicities and mode of action (MoA) co-exist, making single toxicity assessment inadequate to ensure protection of the aquatic environment. This study aimed to characterize the combined toxicity of five environmentally relevant biocides—aclonifen, bifenox, dichlofluanid, metribuzin, and triclosan—with different MoA on growth and photosystem (PS) II efficiency of Chlamydomonas reinhardtii. For growth inhibition, herbicides bifenox and metribuzin were the most toxic, whereas triclosan was least. Only aclonifen and metribuzin exerted a significant effect on PSII, which was also correlated with reduced algal growth. The combined effect of the five biocides on growth inhibition was predominantly additive and presumed to act by independent MoA with potential antagonism observed only at low concentrations and at shorter duration of exposure. The binary mixture of metribuzin and aclonifen exhibited additive effects on diminished PSII efficiency, and effects were apparently induced by an independent MoA. Potential synergy of this mixture on growth inhibition was identified at the highest concentrations. Growth inhibition was found to be a more valuable endpoint for regulatory studies than PSII inhibition due to its environmental relevance, integration of multiple MoA and sensitivity.
- Published
- 2017
8. Measurement of naphthenic acids in the receiving waters around an offshore oil platform by passive sampling
- Author
-
Katherine Langford, Steven Brooks, Rolf Sundt, and Christopher Harman
- Subjects
Marine pollution ,Health, Toxicology and Mutagenesis ,Environmental chemistry ,Environmental Chemistry ,Environmental science ,Submarine pipeline ,North sea ,Produced water ,Passive sampling - Abstract
Polar organic chemical integrative samplers (POCIS) were deployed in the vicinity of an offshore oil installation and analyzed for naphthenic acids (NAs). The POCIS accumulated a range of mono- to tetracyclic NAs, with different degrees of alkylation, with monocyclic acids being the most abundant. Currently, POCIS or similar polar samplers may be the only way to measure exposure to NAs from offshore discharges in situ. In addition, they may be a valuable tool for monitoring similar organic acids in general. Environ Toxicol Chem 2014; 33:1946–1949. © 2014 SETAC
- Published
- 2014
- Full Text
- View/download PDF
9. Release of emamectin from sediment: effects of oil, organic material or infauna?
- Author
-
Eirin Sva Stomperudhaugen, Katherine Langford, Morten Schaanning, and Ketil Hylland
- Subjects
Total organic carbon ,biology ,Chemistry ,Ecology ,Stratigraphy ,Bioirrigation ,Sediment ,Contamination ,biology.organism_classification ,Brissopsis lyrifera ,chemistry.chemical_compound ,Flux (metallurgy) ,Environmental chemistry ,Bioturbation ,Earth-Surface Processes ,Emamectin - Abstract
The aim of this study was to quantify the release of the hydrophobic contaminant emamectin (EMA) from marine sediments in response to inputs of organic material (OM) and/or oil, in the presence or absence of two different bioturbating species. Specifically, it was designed to test whether oil would decrease the release of EMA and whether OM and/or the presence of bioturbating macrofauna would increase the release of EMA from sediment. Experimental sediments were spiked with EMA (5 μg kg−1 wet sediment). The different treatments were prepared by the addition of OM (310 g algae m−2) and/or an aliphatic oil (29.6 g oil m−2). In addition, two bioturbating species, Brissopsis lyrifera or Ennucula tenuis, were added in some aquaria, resulting in a total of 12 treatments with four replicates each. Water samples for analyses of silicate and EMA and sediment samples for analyses of total organic carbon (TOC) were taken at the start and end of the experimental exposure. In addition, oxygen was measured during the experimental period of 8 days. Fluxes were calculated and compared between treatments using generalised linear models (GLMs). The EMA release flux was significantly increased in treatments with added OM, possibly reflecting the presence of soluble complexes formed between EMA and dissolved OM. The presence of B. lyrifera caused a small, but statistically significant, increase in EMA release from sediment. This species would be expected to have a stronger effect on bioirrigation and particle mixing than E. tenuis, particularly when the population density of the latter species is low (as in the present experiment). There were no consistent effects of oil in this experiment, but the presence of oil decreased the EMA release flux when co-occurring with added OM and/or B. lyrifera. Increased retention of hydrophobic contaminants in the presence of oil is consistent with the existing literature on contaminant fate. The results from this study highlight the need to consider both the infauna present in polluted areas and the level of organic enrichment of the sediment when modelling the environmental fate of hydrophobic contaminants. It also highlights that labile OM and refractory oil appear to differ in their effects on the remobilisation of hydrophobic organic contaminants, by reducing and increasing release, respectively.
- Published
- 2014
- Full Text
- View/download PDF
10. Aryl Hydrocarbon Receptor Agonists in European Herring Gull (Larus argentatus) Eggs From Norway
- Author
-
Knut Erik Tollefsen, Kevin V. Thomas, Martine Muusse, Guttorm Christensen, and Katherine Langford
- Subjects
Agonist ,biology ,Norway ,medicine.drug_class ,Eggs ,Health, Toxicology and Mutagenesis ,Gene Expression ,Zoology ,Dioxins ,Toxicology ,Aryl hydrocarbon receptor ,biology.organism_classification ,Charadriiformes ,Receptors, Aryl Hydrocarbon ,Environmental chemistry ,biology.animal ,biology.protein ,medicine ,Animals ,CALUX ,Herring gull ,Luciferases ,Larus ,Environmental Monitoring - Abstract
Herring gull eggs from two locations in Norway, an island situated in the north (Musvaer, 69.88° N, 18.55° E) and an island in the southeast (Reiaren, 59.15° N, 10.46° E) of the country, were analyzed for the presence of aryl hydrocarbon receptor (AhR) agonists. AhR agonist activity was determined using the dioxin-responsive chemically activated luciferase expression (DR-CALUX) assay to calculate the toxic equivalent quotient (TEQ)CALUX. TEQCALUX ranged from 16 to 401 pg TEQ/g lipid in the samples from the north (n = 11) and between 6 and 360 pg TEQ/g lipid (n = 12) in the southeastern samples. The large variance between the individual samples is postulated to be due to different feeding habits of individual birds. The levels of AhR agonists detected might lead to adverse effects for the developing embryo or to a significant increase of contaminant load for human consumers of eggs.
- Published
- 2014
- Full Text
- View/download PDF
11. Extreme irgarol tolerance in an Ulva lactuca L. population on the Swedish west coast
- Author
-
Åsa Arrhenius, Katherine Langford, Ida Wendt, Thomas Backhaus, Timur Tunovic, Hans Blanck, Annelie Hilvarsson, and Kristina Holm
- Subjects
Chlorophyll a ,Zoospore ,Population ,Fjord ,Aquatic Science ,Oceanography ,Risk Assessment ,Ulva ,chemistry.chemical_compound ,Greening ,Algae ,Botany ,West coast ,education ,Ships ,Sweden ,geography ,education.field_of_study ,geography.geographical_feature_category ,biology ,Herbicides ,Triazines ,Ecology ,biology.organism_classification ,Adaptation, Physiological ,Pollution ,chemistry ,Ulva lactuca ,Water Pollutants, Chemical - Abstract
The herbicide irgarol 1051 is commonly used on ship hulls to prevent growth of algae, but as a component of self-eroding paints it can also spread in the surrounding waters and affect non-target organisms. The effect of irgarol on settlement and growth of zoospores from the marine macro algae Ulva lactuca from the Gullmar fjord on the Swedish west coast was investigated in the present study. The zoospores were allowed to settle and grow in the presence of irgarol, but neither settlement – nor growth inhibition was observed at concentrations of up to 2000 nmol l−1. This is between 10 and 100 times higher than effect concentrations reported earlier for algae. Irgarol also induced the greening effect (4-fold increase in chlorophyll a content) in the settled zoospore/germling population, typical for photosystem II inhibitors like irgarol. This study support previous findings that irgarol constitutes a selection pressure in the marine environment.
- Published
- 2013
- Full Text
- View/download PDF
12. Biotransformation kinetics and sorption of cocaine and its metabolites and the factors influencing their estimation in wastewater
- Author
-
Katherine Langford, Kevin V. Thomas, Benedek G. Plósz, Morten Borup, and Malcolm J. Reid
- Subjects
Environmental Engineering ,Metabolite ,Wastewater ,chemistry.chemical_compound ,Cocaine ,Biotransformation ,Humans ,Computer Simulation ,Anaerobiosis ,Waste Management and Disposal ,Water Science and Technology ,Civil and Structural Engineering ,Chromatography ,Ecological Modeling ,Pollution ,Aerobiosis ,Kinetics ,Biodegradation, Environmental ,Activated sludge ,chemistry ,Environmental chemistry ,Benzoylecgonine ,Adsorption ,Xenobiotic ,Quantitative analysis (chemistry) ,Biomarkers ,Water Pollutants, Chemical ,Drug metabolism - Abstract
The quantitative analysis of human urinary metabolites as biomarkers in wastewater streams has been used to estimate the rates of illicit drug use in the wider community. The primary underlying assumption in such studies is that a sample of wastewater is equivalent to a cumulative sample of urine. Drug metabolism in humans is predominantly enzymatically mediated, but these processes are not exclusive to the human body, and are found to occur in the environment and the sewer network. Understanding what happens to drugs and their urinary metabolites in the sewer system between the point of excretion and sampling is particularly important since it is possible that in-sewer transformation may influence final biomarker concentration. The present study uses batch experiments to measure and assess the biotransformation processes of cocaine and its two major human metabolites, benzoylecgonine and ecgonine methyl ester. The activated sludge modelling framework for xenobiotic organic micro-pollutants (ASM-X) is used for model structure identification and calibration. Biotransformation was observed to follow pseudo first-order kinetics. The biodegradation kinetics of cocaine, benzoylecgonine and ecgonine methyl ester is not significantly affected by the availability of dissolved oxygen. Results obtained in this study show that omitting in-pipe biotransformation affects the accuracy of back-calculated cocaine use estimates. This varies markedly depending on the in-sewer hydraulic retention time, total biomass concentration and the relative concentration of each metabolite. However, back-calculated cocaine use estimates derived from wastewater concentrations of benzoylecgonine and ecgonine methyl ester do show very close agreement if ex-vivo biotransformation of these compounds is considered.
- Published
- 2013
- Full Text
- View/download PDF
13. The occurrence of second generation anticoagulant rodenticides in non-target raptor species in Norway
- Author
-
Kevin V. Thomas, Malcolm J. Reid, and Katherine Langford
- Subjects
Bubo ,Eagle ,Veterinary medicine ,Environmental Engineering ,Difenacoum ,Bromadiolone ,Biology ,chemistry.chemical_compound ,biology.animal ,medicine ,Animals ,Environmental Chemistry ,Rodenticide ,Waste Management and Disposal ,Raptors ,Bird Diseases ,Norway ,Flocoumafen ,Poisoning ,Anticoagulants ,Rodenticides ,Pollution ,Difethialone ,Liver ,chemistry ,Rodent Control ,medicine.symptom ,Brodifacoum ,Environmental Monitoring - Abstract
Second generation anticoagulant rodenticides (SGARs) are commonly used for rodent pest control in Norway resulting in the potential exposure of non-target raptor species. In this study the occurrence of flocoumafen, difethialone, difenacoum, bromadiolone and brodifacoum was determined in the livers of five species of raptors found dead in Norway between 2009 and 2011. The SGARs brodifacoum, bromadiolone, difenacoum and flocoumafen were detected in golden eagle ( Aquila chrysaetos ) and eagle owl ( Bubo bubo ) livers at a total SGAR concentration of between 11 and 255 ng/g in approximately 70% of the golden eagles and 50% of the eagle owls examined in this study. In the absence of specific golden eagle and eagle owl toxicity thresholds for SGARs, a level of > 100 ng/g was used as a potential lethal range, accepting that poisoning may occur below this level. Thirty percent (7/24) of the golden eagle and eagle owl livers contained total SGAR residue levels above this threshold. Further estimation of the potential mortality impact on the sampled raptor populations was not possible.
- Published
- 2013
- Full Text
- View/download PDF
14. Characterization of AhR agonist compounds in roadside snow
- Author
-
Gerard Cornelissen, Kevin V. Thomas, Ketil Hylland, Katherine Langford, Knut Erik Tollefsen, Martine Muusse, and Peter Haglund
- Subjects
Agonist ,Chromatography ,biology ,Norway ,medicine.drug_class ,Polychlorinated dibenzodioxins ,Fraction (chemistry) ,Contamination ,Mass spectrometry ,Aryl hydrocarbon receptor ,Biochemistry ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,chemistry.chemical_compound ,Receptors, Aryl Hydrocarbon ,chemistry ,Snow ,Environmental chemistry ,biology.protein ,medicine ,CALUX ,Polycyclic Compounds ,Gas chromatography ,Particle Size - Abstract
Aryl hydrocarbon receptor (AhR) agonistic contaminants were identified in roadside snow samples. Snow was collected in Oslo, Norway, and compared to a background sample collected from a mountain area. The water and particulate fractions were analysed for AhR agonists using a dioxin-responsive, chemically activated luciferase expression (CALUX) cell assay and by gas chromatography coupled to high-resolution time-of-flight mass spectrometry with targeted analysis for polycyclic aromatic hydrocarbons (PAHs) and broad-spectrum non-target analysis. The AhR agonist levels in the dissolved fractions in the roadside samples were between 15 and 387 pg/L CALUX toxic equivalents (TEQ(CALUX)). An elevated AhR activity of 221 pg TEQ(CALUX) per litre was detected in the mountain sample. In the particle-bound fractions, the TEQ(CALUX) was between 1,350 and 7,390 pg/L. One possible explanation for the elevated levels in the dissolved fraction of the mountain sample could be the presence of black carbon in the roadside samples, potentially adsorbing dioxin-like compounds and rendering them unavailable for AhR interaction. No polychlorinated dibenzodioxins and dibenzofurans or polychlorinated biphenyls were detected in the samples; the occurrence of PAHs, however, explained up to 9 % of the AhR agonist activity in the samples, whilst comprehensive two-dimensional gas chromatography coupled to mass spectrometry GCxGC-ToF-Ms identified PAH derivatives such as polycyclic aromatic ketones and alkylated, nitrogen sulphur and oxygen PAHs in the particle fractions. The (large) discrepancy between the total and explained activity highlights the fact that there are other as yet unidentified AhR agonists present in the environment.
- Published
- 2012
- Full Text
- View/download PDF
15. Lack of response in a marine pelagic community to short-term oil and contaminant exposure
- Author
-
Katherine Langford, Ketil Hylland, and Hege Vestheim
- Subjects
Ecology ,Pelagic zone ,Aquatic Science ,Contamination ,Biology ,Food web ,Mesocosm ,chemistry.chemical_compound ,Nutrient ,chemistry ,Environmental chemistry ,medicine ,Mineral oil ,Microcosm ,Ecology, Evolution, Behavior and Systematics ,medicine.drug ,Emamectin - Abstract
Oil and contaminant inputs are co-occurring features of most estuaries and harbours in industrialised countries. However, there is limited knowledge as to how these different pressures interact. Oil may modulate the accumulation and effects of contaminants, and community response to contaminant stress would be expected to be coupled to food web structure. We performed an outdoor land-based 100-L microcosm experiments using natural coastal sea water in order to address these questions. Either mineral oil, emamectin (EMA; a pharmaceutical used in aquaculture and agriculture), or a combination was dosed to three replicate tanks for each treatment. Samples were taken at the start and each day of a four-day exposure period. For each sample, algal production and nutrients were quantified. Bacterial abundance was assessed by flow cytometry and the fate of emamectin investigated by filtration followed by extraction and LC/MS/MS analysis. Mesozooplankton were counted in samples taken at the end of the experiment. There were clear changes in chlorophyll a and bacterial numbers over the time course of the experiment in all treatments, but addition of oil, EMA or their combination did not alter nutrient concentrations, ecosystem components or the community structure compared to the control. There was however an unexplained apparent positive effect of low concentrations of acetone (0.005%) used as solvent in the mesocosms. Emamectin was predominantly found in the water phase at the end of the experiment with higher concentrations in both fractions of EMA–oil treatments compared to treatments with EMA only. The study shows that even high concentrations of the environmental stressors oil and emamectin may not have dramatic effects in a dynamic pelagic system over a four-day period, presumably indicating that longer exposure will be required for any effects through top-down processes to become evident.
- Published
- 2012
- Full Text
- View/download PDF
16. Effects of Dispersed Aggregates of Carbon and Titanium Dioxide Engineered Nanoparticles on Rainbow Trout Hepatocytes
- Author
-
Julia Farkas, Quinglan Wu, Katherine Langford, Kevin V. Thomas, Knut Erik Tollefsen, Eivind Farmen, and Paul Christian
- Subjects
Fullerene ,Health, Toxicology and Mutagenesis ,chemistry.chemical_element ,Nanoparticle ,Fresh Water ,Nanotechnology ,Toxicology ,Nanomaterials ,chemistry.chemical_compound ,Animals ,Particle Size ,Cytotoxicity ,Titanium ,Cytotoxins ,Cobalt ,Carbon ,Oxidative Stress ,chemistry ,Chemical engineering ,Oncorhynchus mykiss ,Titanium dioxide ,Hepatocytes ,Nanoparticles ,Engineered Nanoparticle ,Reactive Oxygen Species ,Water Pollutants, Chemical - Abstract
The purpose of this study was to investigate the cytotoxicity and oxidative stress responses of selected engineered carbon and titanium dioxide (TiO2) nanomaterials to rainbow trout (Oncorhynchus mykiss) primary hepatocytes. The engineered nanomaterials tested were C(60) fullerenes, multiwall nanotubes (MWNT), single-wall nanotubes (SWNT) (functionalized and nonfunctionalized), and TiO2 of 5 and 200 nm in size. Characterization of these materials showed that they were typically present in solution as agglomerates. The engineered nanoparticle agglomerates were cytotoxic at nominal concentrations of3 mg/L, and certain MWNT and SWNT produced significant intracellular reactive oxygen species (ROS) production as well as cytotoxicity. Analyses of the MWNT responsible for ROS production and cytotoxicity for selected transition metals demonstrated the presence of residual cobalt (Co), which was not present in the nonreactive/non-bioactive MWNT. Cobalt alone was not able to induce the observed effects in hepatocyte cells; however, coexposure with MWNT resulted in an increase in cytotoxicity. Data suggest that trace metals often associated with commercial nanotubes are responsible for the observed biological effects. In addition, other mechanisms, such as the proposed facilitated transport (e.g., Trojan horse) type mechanism of uptake, may provoke an increased response compared to aqueous exposures of trace metals in the absence of carbon nanoparticles.
- Published
- 2011
- Full Text
- View/download PDF
17. Determination of pharmaceutical compounds in hospital effluents and their contribution to wastewater treatment works
- Author
-
Kevin V. Thomas and Katherine Langford
- Subjects
Drug ,media_common.quotation_subject ,Waste Disposal, Fluid ,Mass Spectrometry ,medicine ,Medical Waste Disposal ,Effluent ,Environmental Restoration and Remediation ,lcsh:Environmental sciences ,General Environmental Science ,media_common ,lcsh:GE1-350 ,Waste management ,Chemistry ,Atenolol ,Pulp and paper industry ,Hospitals ,Waste treatment ,Pharmaceutical Preparations ,Wastewater ,Anti cancer drugs ,Sewage treatment ,Water Pollutants, Chemical ,Chromatography, Liquid ,medicine.drug ,Waste disposal - Abstract
A method was developed for the simultaneous determination of almost 40 pharmaceuticals; including antidepressants, non-steroidal anti-inflammatories, analgesics, hypolipidemics, α- and β-blockers, an anti cancer drug, anti-fungal agents, an opiate, an antibiotic, an anti-coagulant, a diuretic, an anti-anginal and an anti-diabetic compound. This was used to assess the contribution of pharmaceuticals originating from hospital effluents to one of Oslo city's wastewater treatment works. Some pharmaceuticals were found to contribute to more of the wastewater loading than others. 11% of the propranolol entering the wastewater treatment works stems from hospital effluent, approximately 2% of the atenolol, carbemazepine, metaprolol and atorvastatin, and for several other compounds the contribution is less than 1%.This assessment shows that point sources discharges from hospitals typically make a small contribution to the overall pharmaceutical load when compared to municipal areas, however this varies from substance to substance and is not the case when a drug's use is primarily hospital based. Keywords: Pharmaceuticals, LC/MS, Wastewater, Hospitals
- Published
- 2008
18. A two stage algorithm for target and suspect analysis of produced water via gas chromatography coupled with high resolution time of flight mass spectrometry
- Author
-
Katherine Langford, Saer Samanipour, Malcolm J. Reid, and Kevin V. Thomas
- Subjects
Target analysis ,010501 environmental sciences ,Signal-To-Noise Ratio ,01 natural sciences ,Biochemistry ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,Calibration ,Blossom algorithm ,0105 earth and related environmental sciences ,Chromatography ,Chemistry ,010401 analytical chemistry ,Organic Chemistry ,Water ,General Medicine ,Hydrocarbons ,0104 chemical sciences ,Signal-to-noise ratio (imaging) ,Stage (hydrology) ,Gas chromatography ,Gas chromatography–mass spectrometry ,Time-of-flight mass spectrometry ,Algorithms ,Water Pollutants, Chemical - Abstract
Gas chromatography coupled with high resolution time of flight mass spectrometry (GC–HR-TOFMS) has gained popularity for the target and suspect analysis of complex samples. However, confident detection of target/suspect analytes in complex samples, such as produced water, remains a challenging task. Here we report on the development and validation of a two stage algorithm for the confident target and suspect analysis of produced water extracts. We performed both target and suspect analysis for 48 standards, which were a mixture of 28 aliphatic hydrocarbons and 20 alkylated phenols, in 3 produced water extracts. The two stage algorithm produces a chemical standard database of spectra, in the first stage, which is used for target and suspect analysis during the second stage. The first stage is carried out through five steps via an algorithm here referred to as unique ion extractor (UIE). During the first step the m/z values in the spectrum of a standard that do not belong to that standard are removed in order to produce a clean spectrum and then during the last step the cleaned spectrum is calibrated. The Dot-product algorithm, during the second stage, uses the cleaned and calibrated spectra of the standards for both target and suspect analysis. We performed the target analysis of 48 standards in all 3 samples via conventional methods, in order to validate the two stage algorithm. The two stage algorithm was demonstrated to be more robust, reliable, and less sensitive to the signal-to-noise ratio (S/N), when compared to the conventional method. The Dot-product algorithm showed lower potential in producing false positives compared to the conventional methods, when dealing with complex samples. We also evaluated the effect of the mass accuracy on the performances of Dot-product algorithm. Our results indicated the crucial importance of HR-MS data and the mass accuracy for confident suspect analysis in complex samples.
- Published
- 2016
19. Identification of petrogenic produced water components as acetylcholine esterase inhibitors
- Author
-
Inger Lise Nerland Bråte, Katherine Langford, Kevin V. Thomas, Steven Brooks, Knut Erik Tollefsen, and Jean Froment
- Subjects
Fish Proteins ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,010501 environmental sciences ,Toxicology ,Mass spectrometry ,01 natural sciences ,High-performance liquid chromatography ,Gas Chromatography-Mass Spectrometry ,chemistry.chemical_compound ,Pollachius virens ,Butylated hydroxytoluene ,Animals ,Seawater ,Solid phase extraction ,Polycyclic Aromatic Hydrocarbons ,Chromatography, High Pressure Liquid ,0105 earth and related environmental sciences ,chemistry.chemical_classification ,Chromatography ,biology ,Solid Phase Extraction ,Fishes ,General Medicine ,biology.organism_classification ,Pollution ,Produced water ,Enzyme ,chemistry ,Acetylcholinesterase ,Gas chromatography ,Cholinesterase Inhibitors ,North Sea ,Water Pollutants, Chemical - Abstract
Effect-directed analysis (EDA) was applied to identify acetylcholine esterase (AChE) inhibitors in produced water. Common produced water components from oil production activities, such as polycyclic aromatic hydrocarbons (PAHs), alkylphenols, and naphthenic acids were tested for AChE inhibition using a simple mixture of PAHs and naphthenic acids. Produced water samples collected from two offshore platforms in the Norwegian sector of the North Sea were extracted by solid phase extraction and fractionated by open-column liquid solid chromatography and high-performance liquid chromatography (HPLC) before being tested using a high-throughput and automated AChE assay. The HPLC fractions causing the strongest AChE inhibition were analysed by gas chromatography coupled to a high-resolution time-of-flight mass spectrometry (GC-HR-ToF-MS). Butylated hydroxytoluene and 4-phenyl-1,2-dihydronaphthalene were identified as two produced water components capable of inhibiting AChE at low concentrations. In order to assess the potential presence of such compounds discharged into aquatic ecosystems, AChE activity in fish tissues was measured. Saithe (Pollachius virens) caught near two offshore platforms showed lower enzymatic activity than those collected from a reference location. Target analysis of saithe did not detected the presence of these two putative AChE inhibitors and suggest that additional compounds such as PAHs, naphthenic acids and yet un-identified compounds may also contribute to the purported AChE inhibition observed in saithe.
- Published
- 2016
20. Degradation of nonylphenolic surfactants in activated sludge batch tests
- Author
-
Mark D. Scrimshaw, John N. Lester, Katherine Langford, and Jason W. Birkett
- Subjects
endocrine system ,Time Factors ,Environmental Engineering ,Endocrine System ,Waste Disposal, Fluid ,Surface-Active Agents ,chemistry.chemical_compound ,Phenols ,Waste Management and Disposal ,Water Science and Technology ,Civil and Structural Engineering ,Chromatography ,Sewage ,biology ,Ecological Modeling ,Biodegradation ,Pollution ,Enzyme assay ,Nonylphenol ,Biodegradation, Environmental ,Activated sludge ,Endocrine disruptor ,chemistry ,Wastewater ,Environmental chemistry ,biology.protein ,Degradation (geology) ,Sewage treatment ,Water Pollutants, Chemical - Abstract
The fate of nonylphenol polyethoxylate surfactants in the activated sludge wastewater treatment process is a concern due to the formation of estrogenic nonlyphenols on degradation and due to the large amounts discharged to the aquatic environment through sewage treatment works. Batch tests using activated sludge from a Husmann apparatus were used to determine the effects of these compounds physico-chemical properties and biological sludge characteristics on biodegradation. Degradation of nonylphenol polyethoxylates with up to 12 ethoxy groups was observed in unacclimated sludge with a concomitant production of nonylphenol and short chain nonylphenol polyethoxylate compounds. Degradation was determined to be a biotic process involving intracellular enzyme activity, which resulted in sludge age being an influential parameter. With increasing sludge age there is an increase in mixed liquor solids concentration in activated sludge which results in greater bacterial numbers and the potential for greater species diversity which therefore increases compound degradation. However, increased degradation of long chain compounds resulted in an accumulation of shorter chain compounds and nonylphenol, which are more resistant to degradation.
- Published
- 2005
- Full Text
- View/download PDF
21. Analytical Methods for the Determination of Alkylphenolic Surfactants and Polybrominated Diphenyl Ethers in Wastewaters and Sewage Sludges. II Method Development
- Author
-
John N. Lester, Mark D. Scrimshaw, and Katherine Langford
- Subjects
Chromatography ,Aqueous solution ,Sewage ,Chemistry ,Phenyl Ethers ,Polybrominated Biphenyls ,Extraction (chemistry) ,Aqueous two-phase system ,General Medicine ,Gas Chromatography-Mass Spectrometry ,Solvent ,Surface-Active Agents ,Electron capture detector ,Polybrominated diphenyl ethers ,Phenols ,Liquid–liquid extraction ,Environmental chemistry ,Halogenated Diphenyl Ethers ,Environmental Chemistry ,Waste Management and Disposal ,Water Pollutants, Chemical ,Sludge ,Chromatography, Liquid ,Environmental Monitoring ,Water Science and Technology - Abstract
Analytical methods for the determination of two groups of compounds, the non-polar alkyl phenols along with their more polar ethoxylates, and the hydrophobic polybrominated flame retardants in wastewater samples have been developed. The methods allow for determination of the analytes in both the aqueous and solid phases, which were separated by centrifugation and filtration. Extraction from the aqueous phase involved the use of SPE for the surfactants, however, liquid-liquid extraction was found to be more efficient for the PBDE. Alkyl phenols and their ethoxylates were extracted from the solid phase by shaking with solvent and Soxhlet was used for extraction of PBDE. Sample cleanup was based on alumina columns for the PBDE and surfactants when extracted form solids. Quantification of surfactants utilised LC-MS with ESI in both positive and negative ionisation mode, and GC-MS (NCI) was used to determine the PBDE, with the exception of the deca congener, where a 10 m column installed on GC-ECD resulted in short run times and reduced thermal decomposition. Method recoveries for the surfactants were above 80%, and for PBDE 92.5% from the solid phase and 95+/-5% from the liquid phase.
- Published
- 2004
- Full Text
- View/download PDF
22. Legemidler som forurensning
- Author
-
Merete Grung, Katherine Langford, and Kevin V. Thomas
- Subjects
Chronic exposure ,Pollution ,education.field_of_study ,media_common.quotation_subject ,Population ,General Medicine ,complex mixtures ,Environmentally friendly ,Aquatic organisms ,Environmental risk ,Aquatic environment ,Environmental health ,Environmental science ,Sewage treatment ,education ,media_common - Abstract
The pharmaceuticals we humans use to treat illness and disease typically enter the aquatic environment via the sewer network and wastewater treatment works. Understanding the risks posed to the aquatic environment by these chemicals requires an understanding of the concentrations that exist in the environment and whether they are sufficiently high to have adverse effects on aquatic organisms. The main source of pharmaceuticals to wastewater treatment works is pharmaceuticals used by the general population. Only a small contribution is believed to come from hospitals. The predicted environmental concentrations of pharmaceuticals suggest that certain pharmaceuticals may pose a risk to the environment, but measurement of the actual concentrations present in effluents and recipient waters suggest that sophisticated wastewater treatment is effective for significantly reducing effluent concentrations, and that environmental concentrations of pharmaceuticals, in the Oslo Fjord, for example, are generally low. Humans also excrete the metabolites of the pharmaceuticals that they have used and these too may be released into the environment, sometimes in greater concentrations than the parent drug. The occurrence of most pharmaceuticals and their metabolites in the environment poses little acute environmental risk. However, the effects of long-term chronic exposure to these compounds are still poorly understood and the long-terms risks to the environment are still not clear. What is clear is that certain pharmaceuticals pose a greater environmental risk than others, and that where possible this knowledge should be used to inform users of more environmentally friendly alternatives.
- Published
- 2012
- Full Text
- View/download PDF
23. Environmental occurrence and risk of organic UV filters and stabilizers in multiple matrices in Norway
- Author
-
Kevin V. Thomas, Katherine Langford, Eirik Fjeld, Malcolm J. Reid, and Sigurd Øxnevad
- Subjects
Risk ,Aquatic Organisms ,Geologic Sediments ,UV filter ,Fresh Water ,Wastewater ,chemistry.chemical_compound ,Animals ,Leachate ,Effluent ,lcsh:Environmental sciences ,General Environmental Science ,lcsh:GE1-350 ,Total organic carbon ,Sewage ,Norway ,Fishes ,Biota ,Octocrylene ,chemistry ,Environmental chemistry ,Bioaccumulation ,Sewage treatment ,Sunscreening Agents ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
Eight organic UV filters and stabilizers were quantitatively determined in wastewater sludge and effluent, landfill leachate, sediments, and marine and freshwater biota. Crab, prawn and cod from Oslofjord, and perch, whitefish and burbot from Lake Mjøsa were selected in order to evaluate the potential for trophic accumulation. All of the cod livers analysed were contaminated with at least 1 UV filter, and a maximum concentration of almost 12 μg/g wet weight for octocrylene (OC) was measured in one individual. 80% of the cod livers contained OC, and approximately 50% of cod liver and prawn samples contained benzophenone (BP3). Lower concentrations and detection frequencies were observed in freshwater species and the data of most interest is the 4 individual whitefish that contained both BP3 and ethylhexylmethoxycinnamate (EHMC) with maximum concentrations of almost 200 ng/g wet weight. The data shows a difference in the loads of UV filters entering receiving water dependent on the extent of wastewater treatment. Primary screening alone is insufficient for the removal of selected UV filters (BP3, Padimate, EHMC, OC, UV-234, UV-327, UV-328, UV-329). Likely due in part to the hydrophobic nature of the majority of the UV filters studied, particulate loading and organic carbon content appear to be related to concentrations of UV filters in landfill leachate and an order of magnitude difference in these parameters correlates with an order of magnitude difference in the effluent concentrations of selected UV filters (Fig. 2). From the data, it is possible that under certain low flow conditions selected organic UV filters may pose a risk to surface waters but under the present conditions the risk is low, but some UV filters will potentially accumulate through the trophic food chain. Keywords: UV filters, UV stabilizers, Sunscreen, Bioaccumulation, Wastewater, Landfill leachate
- Published
- 2014
24. Benzoylurea pesticides used as veterinary medicines in aquaculture: Risks and developmental effects on nontarget crustaceans
- Author
-
Ailbhe, Macken, Adam, Lillicrap, and Katherine, Langford
- Subjects
Copepoda ,Life Cycle Stages ,Ivermectin ,Benzamides ,Organothiophosphates ,Toxicity Tests, Acute ,Animals ,Veterinary Drugs ,Aquaculture ,Diflubenzuron ,Pesticides ,Disaccharides ,Water Pollutants, Chemical - Abstract
Diflubenzuron and teflubenzuron are benzoylureas that are used in aquaculture to control sea lice. Flubenzurons have low toxicity to many marine species such as fish and algae but by their nature are likely to have significant adverse effects on nontarget species such as crustaceans and amphipods. Although the exact mechanism of toxicity is not known, these compounds are thought to inhibit the production of the enzyme chitin synthase during molting of immature stages of arthropods. These chitin synthesis inhibitors are effective against the larval and pre-adult life stages of sea lice. Due to their low solubility and results of recent monitoring studies conducted in Norway, the sediment compartment is considered the most likely reservoir for these compounds and possible remobilization from the sediment to benthic crustaceans could be of importance. For this reason, the epibenthic copepod Tisbe battagliai was selected for investigations into the acute and developmental effects of these compounds. For comparative purposes, azamethiphos was investigated to identify differences in sensitivity and act as a negative control for developmental effects at environmentally relevant concentrations. Standard acute studies with adult copepods showed little or no acute toxicity at milligrams per liter levels with the flubenzurons, whereas a naupliar developmental test demonstrated that environmentally relevant concentrations (e.g., nanograms per liter) caused a complete cessation of molting and finally death in the exposed copepods.
- Published
- 2014
25. Characterization of AhR agonists reveals antagonistic activity in European herring gull (Larus argentatus) eggs
- Author
-
Guttorm Christensen, Knut Erik Tollefsen, Lenka Vaňková, Katherine Langford, Martine Muusse, Tânia Gomes, Kevin V. Thomas, and Anton Kočan
- Subjects
Environmental Engineering ,Eggs ,Dioxins ,Northern norway ,chemistry.chemical_compound ,Charadriiformes ,Herring ,biology.animal ,South east ,Environmental Chemistry ,CALUX ,Animals ,Food science ,Waste Management and Disposal ,Ovum ,biology ,Chemistry ,Norway ,Hexachlorobenzene ,biology.organism_classification ,Aryl hydrocarbon receptor ,Pollution ,Receptors, Aryl Hydrocarbon ,Environmental chemistry ,embryonic structures ,biology.protein ,Herring gull ,Environmental Pollutants ,Larus ,Biomarkers ,Environmental Monitoring - Abstract
European herring gull ( Larus argentatus ) eggs from two Norwegian islands, Musvaer in the south east and Reiaren in Northern Norway, were screened for dioxins, furans, and dioxin-like and selected non-dioxin-like polychlorinated biphenyls (PCBs), and subjected to non-target analysis to try to identify the aryl hydrocarbon receptor (AhR) agonists, responsible for elevated levels measured using the dioxin responsive chemically activated luciferase expression (DR-CALUX) assay. Eggs from Musvaer contained chemically calculated toxic equivalent (WHO TEQ) levels of between 109 and 483 pg TEQ/g lw, and between 82 and 337 pg TEQ/g lw was determined in eggs from Reiaren. In particular PCB126 contributed highly to the total TEQ (69–82%). In 19 of the 23 samples the calculated WHO TEQ was higher than the TEQ CALUX . Using CALUX specific relative effect potencies (REPs), the levels were lower at between 77 and 292 pg/g lw in eggs from Musvaer and between 55 and 223 pg/g lw in eggs from Reiaren, which was higher than the TEQ CALUX in 16 of the 23 samples. However, the means of the REP values and the TEQ CALUX were not significantly different. This suggests the presence of compounds that can elicit antagonist effects, with a low binding affinity to the AhR. Non-target analysis identified the presence of hexachlorobenzene (HCB) (quantified at 9.6–185 pg/g lw) but neither this compound nor high concentrations of PCB126 and non-dioxin-like PCBs could explain the differences between the calculated TEQ or REP values and the TEQ CALUX . Even though, for most AhR agonists, the sensitivity of herring gulls is not known, the reported levels can be considered to represent a risk for biological effects in the developing embryo, compared to LC50 values in chicken embryos. For human consumers of herring gull eggs, these eggs contain TEQ levels up to four times higher than the maximum tolerable weekly intake.
- Published
- 2014
26. Do antiparasitic medicines used in aquaculture pose a risk to the Norwegian aquatic environment?
- Author
-
Sigurd Øxnevad, Katherine Langford, Merete Schøyen, and Kevin V. Thomas
- Subjects
Aquatic Organisms ,Cost effectiveness ,Aquaculture ,Biology ,Risk Assessment ,Cypermethrin ,Toxicology ,chemistry.chemical_compound ,Risk Factors ,Water Supply ,Crustacea ,Nitriles ,Pyrethrins ,Environmental Chemistry ,Animals ,Environmental quality ,Ivermectin ,Antiparasitic Agents ,business.industry ,Norway ,Water ,Biota ,General Chemistry ,Reference Standards ,Shrimp ,Fishery ,Diflubenzuron ,Deltamethrin ,chemistry ,Benzamides ,business ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
Aquaculture production is an important industry in many countries and there has been a growth in the use of medicines to ensure the health and cost effectiveness of the industry. This study focused on the inputs of sea lice medication to the marine environment. Diflubenzuron, teflubenzuron, emamectin benzoate, cypermethrin, and deltamethrin were measured in water, sediment, and biota samples in the vicinity of five aquaculture locations along the Norwegian coast. Deltamethrin and cypermethrin were not detected above the limits of detection in any samples. Diflubenzuron, teflubenzuron, and emamectin benzoate were detected, and the data was compared the UK Environmental Quality Standards. The concentrations of emamectin benzoate detected in sediments exceed the environmental quality standard (EQS) on 5 occasions in this study. The EQS for teflubenzuron in sediment was exceeded in 67% of the samples and exceeded for diflubenzuron in 40% of the water samples collected. A crude assessment of the concentrations detected in the shrimp collected from one location and the levels at which chronic effects are seen in shrimp would suggest that there is a potential risk to shrimp. It would also be reasonable to extrapolate this to any species that undergoes moulting during its life cycle.
- Published
- 2014
27. Polybrominated diphenyl ether (PBDE) flame retardants
- Author
-
Katherine Langford, Frank Rahman, Mark D. Scrimshaw, and John N. Lester
- Subjects
Male ,Pollution ,endocrine system ,Environmental Engineering ,media_common.quotation_subject ,Polybrominated Biphenyls ,Dioxins ,Mice ,Structure-Activity Relationship ,chemistry.chemical_compound ,Risk Factors ,Occupational Exposure ,Halogenated Diphenyl Ethers ,Animals ,Humans ,Environmental Chemistry ,Ecotoxicology ,Waste Management and Disposal ,Toxic equivalency factor ,reproductive and urinary physiology ,Flame Retardants ,media_common ,Molecular Structure ,Phenyl Ethers ,Diphenyl ether ,Particulates ,Polychlorinated Biphenyls ,humanities ,Hydrocarbons, Brominated ,chemistry ,Phthalic Anhydrides ,Bioaccumulation ,Environmental chemistry ,Environmental Pollutants ,Fire retardant - Abstract
Polybrominated diphenyl ether, PBDE, flame retardants are now a world-wide pollution problem reaching even remote areas. They have been found to bioaccumulate and there are concerns over the health effects of exposure to PBDEs, they also have potential endocrine disrupting properties. They are lipophilic compounds so are easily removed from the aqueous environment and are predicted to sorb onto sediments and particulate matter or to fatty tissue, aiding their distribution throughout the environment. PBDEs are structurally similar to PCBs and DDT and, therefore, their chemical properties, persistence and distribution in the environment follow similar patterns. Concentrations of PBDEs found in environmental samples are now higher than those of PCBs. Evidence to date demonstrates that PBDEs are a growing problem in the environment and concern over their fate and effects is warranted. The manufacture of reactive and additive flame retardants is briefly discussed and their fate and behaviour in the environment is assessed. PBDE toxicology is reviewed and methods of analysis are evaluated.
- Published
- 2001
- Full Text
- View/download PDF
28. Measurement of naphthenic acids in the receiving waters around an offshore oil platform by passive sampling
- Author
-
Christopher, Harman, Katherine, Langford, Rolf C, Sundt, and Steven, Brooks
- Subjects
Carboxylic Acids ,Water ,Oil and Gas Fields ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
Polar organic chemical integrative samplers (POCIS) were deployed in the vicinity of an offshore oil installation and analyzed for naphthenic acids (NAs). The POCIS accumulated a range of mono- to tetracyclic NAs, with different degrees of alkylation, with monocyclic acids being the most abundant. Currently, POCIS or similar polar samplers may be the only way to measure exposure to NAs from offshore discharges in situ. In addition, they may be a valuable tool for monitoring similar organic acids in general.
- Published
- 2014
29. Effects of five antifouling biocides on settlement and growth of zoospores from the marine macroalga Ulva lactuca L
- Author
-
Åsa Arrhenius, Katherine Langford, Timur Tunovic, Hans Blanck, Ida Wendt, Thomas Backhaus, Kristina Holm, and Annelie Hilvarsson
- Subjects
Biocide ,biology ,Pyridines ,Health, Toxicology and Mutagenesis ,Copper toxicity ,Lactuca ,General Medicine ,Toxicology ,biology.organism_classification ,medicine.disease ,Pollution ,Biofouling ,Ulva ,Environmental chemistry ,Toxicity ,Botany ,medicine ,Ecotoxicology ,Ulva lactuca ,Boranes ,Copper ,Water Pollutants, Chemical ,EC50 ,Disinfectants - Abstract
Antifouling biocides are found in the marine ecosystem were they can affect non-target organisms. In this study the effects of five antifouling biocides on the settlement and growth of Ulva lactuca zoospores were investigated. The biocides investigated were copper (Cu(2+)), 4,5-dichloro-2-n-octyl-3(2H)-isothiazolone (DCOIT), triphenylborane pyridine (TPBP), tolylfluanid and medetomidine. Full concentration-response curves where determined for each compound. EC50 values were determined for copper, DCOIT, TPBP and tolylfluanid, all of which inhibited settlement and growth in a concentration dependent manner with the following toxicity ranking; tolylfluanid (EC50 80 nmol L(-1)) ~ DCOIT (EC50 83 nmol L(-1)) > TPBP (EC50 400 nmol L(-1)) > Cu(2+) (EC50 2,000 nmol L(-1)). Medetomidine inhibited settlement and growth only at the extreme concentration of 100,000 nmol L(-1) (93% effect). The low toxicity is possibly a consequence of a lack of receptors that medetomidine can bind to in the U. lactuca zoospores.
- Published
- 2013
30. Estimation of cocaine consumption in the community: a critical comparison of the results from three complimentary techniques
- Author
-
Hallvard Gjerde, Jørg Mørland, Katherine Langford, Merete Grung, Malcolm J. Reid, Kevin V. Thomas, and Ellen J. Amundsen
- Subjects
media_common.quotation_subject ,Population ,Survey sampling ,Oral Fluid Analysis ,Cocaine ,Statistics ,Range (statistics) ,Population Survey ,Medicine ,Quality (business) ,Set (psychology) ,education ,media_common ,Consumption (economics) ,Estimation ,education.field_of_study ,business.industry ,Research ,General Medicine ,Drug Epidemiology ,Cocaine use ,Sewage Analysis ,Public Health ,business - Abstract
Objectives A range of approaches are now available to estimate the level of drug use in the community so it is desirable to critically compare results from the differing techniques. This paper presents a comparison of the results from three methods for estimating the level of cocaine use in the general population. Design The comparison applies to; a set of regional-scale sample survey questionnaires, a representative sample survey on drug use among drivers and an analysis of the quantity of cocaine-related metabolites in sewage. Setting 14 438 participants provided data for the set of regional-scale sample survey questionnaires; 2341 drivers provided oral-fluid samples and untreated sewage from 570 000 people was analysed for biomarkers of cocaine use. All data were collected in Oslo, Norway. Results 0.70 (0.36–1.03) % of drivers tested positive for cocaine use which suggest a prevalence that is higher than the 0.22 (0.13–0.30) % (per day) figure derived from regional-scale survey questionnaires, but the degree to which cocaine consumption in the driver population follows the general population is an unanswered question. Despite the comparatively low-prevalence figure the survey questionnaires did provide estimates of the volume of consumption that are comparable with the amount of cocaine-related metabolites in sewage. Per-user consumption estimates are however highlighted as a significant source of uncertainty as little or no data on the quantities consumed by individuals are available, and much of the existing data are contradictory. Conclusions The comparison carried out in the present study can provide an excellent means of checking the quality and accuracy of the three measurement techniques because they each approach the problem from a different viewpoint. Together the three complimentary techniques provide a well-balanced assessment of the drug-use situation in a given community and identify areas where more research is needed.
- Published
- 2012
31. Modelling micro-pollutant fate in wastewater collection and treatment systems: status and challenges
- Author
-
Benedek G. Plósz, Katherine Langford, Christoph Ort, Peter A. Vanrolleghem, Henrik Fred Larsen, Glen T. Daigger, Lorenzo Benedetti, Rajesh Seth, h. Monteith, Jean-Philippe Steyer, Technical University of Denmark [Lyngby] (DTU), Norwegian Institute for Water Research (NIVA), Universiteit Gent = Ghent University [Belgium] (UGENT), CH2M Hill Inc, Partenaires INRAE, Hydromantis Environm Software Solut Inc, Central Queensland University (CQU), Urban Water Management, Swiss Federal institute of aquatic science and technology, University of Windsor [Ca], Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Dept Genie Civil & Genie Eaux, ModelEAU, Université Laval [Québec] (ULaval), Norwegian Research Council [SIP-ES243159], Norwegian Institute for Water Research, NIVA [O10091], NSERC, and European Union [036845, SUSTDEV-2005-3.H.3.2]
- Subjects
Environmental Engineering ,trace chemicals ,Adsorption desorption ,[SDV]Life Sciences [q-bio] ,media_common.quotation_subject ,0207 environmental engineering ,02 engineering and technology ,010501 environmental sciences ,parent chemical retransformation ,01 natural sciences ,Risk Assessment ,Waste Disposal, Fluid ,Xenobiotics ,Bioreactors ,risk assessment and regulations ,Environmental monitoring ,media_common.cataloged_instance ,Quality (business) ,Anaerobiosis ,European Union ,European union ,Cities ,020701 environmental engineering ,Environmental planning ,0105 earth and related environmental sciences ,Water Science and Technology ,media_common ,Pollutant ,Environmental engineering ,Models, Theoretical ,6. Clean water ,biotransformation and cometabolism ,Wastewater ,13. Climate action ,sorption-desorption ,[SDE]Environmental Sciences ,North America ,Environmental science ,Risk assessment ,Water Pollutants, Chemical ,Waste disposal ,Environmental Monitoring - Abstract
International audience; This paper provides a comprehensive summary on modelling of micro-pollutants' (MPs) fate and transport in wastewater. It indicates the motivations of MP modelling and summarises and illustrates the current status. Finally, some recommendations are provided to improve and diffuse the use of such models. In brief, we conclude that, in order to predict the contaminant removal in centralised treatment works, considering the dramatic improvement in monitoring and detecting MPs in wastewater, more mechanistic approaches should be used to complement conventional, heuristic and other fate models. This is crucial, as regional risk assessments and model-based evaluations of pollution discharge from urban areas can potentially be used by decision makers to evaluate effluent quality regulation, and assess upgrading requirements, in the future.
- Published
- 2012
- Full Text
- View/download PDF
32. [Pharmaceuticals as pollution]
- Author
-
Merete, Grung, Katherine, Langford, and Kevin V, Thomas
- Subjects
Drug-Related Side Effects and Adverse Reactions ,Sewage ,Norway ,Humans ,Environmental Exposure ,Risk Assessment ,Drug Residues - Abstract
The pharmaceuticals we humans use to treat illness and disease typically enter the aquatic environment via the sewer network and wastewater treatment works. Understanding the risks posed to the aquatic environment by these chemicals requires an understanding of the concentrations that exist in the environment and whether they are sufficiently high to have adverse effects on aquatic organisms. The main source of pharmaceuticals to wastewater treatment works is pharmaceuticals used by the general population. Only a small contribution is believed to come from hospitals. The predicted environmental concentrations of pharmaceuticals suggest that certain pharmaceuticals may pose a risk to the environment, but measurement of the actual concentrations present in effluents and recipient waters suggest that sophisticated wastewater treatment is effective for significantly reducing effluent concentrations, and that environmental concentrations of pharmaceuticals, in the Oslo Fjord, for example, are generally low. Humans also excrete the metabolites of the pharmaceuticals that they have used and these too may be released into the environment, sometimes in greater concentrations than the parent drug. The occurrence of most pharmaceuticals and their metabolites in the environment poses little acute environmental risk. However, the effects of long-term chronic exposure to these compounds are still poorly understood and the long-terms risks to the environment are still not clear. What is clear is that certain pharmaceuticals pose a greater environmental risk than others, and that where possible this knowledge should be used to inform users of more environmentally friendly alternatives.
- Published
- 2012
33. An activated sludge modeling framework for xenobiotic trace chemicals (ASM-X): assessment of diclofenac and carbamazepine
- Author
-
Kevin V. Thomas, Katherine Langford, and Benedek G. Plósz
- Subjects
Diclofenac ,Sewage ,Bioengineering ,Carbamazepine ,Applied Microbiology and Biotechnology ,Anoxic waters ,Models, Biological ,Water Purification ,Xenobiotics ,chemistry.chemical_compound ,Activated sludge ,Wastewater ,chemistry ,Biotransformation ,Environmental chemistry ,medicine ,Environmental science ,Sewage treatment ,Xenobiotic ,Water Pollutants, Chemical ,Biotechnology ,medicine.drug - Abstract
Conventional models for predicting the fate of xenobiotic organic trace chemicals, identified, and calibrated using data obtained in batch experiments spiked with reference substances, can be limited in predicting xenobiotic removal in wastewater treatment plants (WWTPs). At stake is the level of model complexity required to adequately describe a general theory of xenobiotic removal in WWTPs. In this article, we assess the factors that influence the removal of diclofenac and carbamazepine in activated sludge, and evaluate the complexity required for the model to effectively predict their removal. The results are generalized to previously published cases. Batch experimental results, obtained under anoxic and aerobic conditions, were used to identify extensions to, and to estimate parameter values of the activated sludge modeling framework for Xenobiotic trace chemicals (ASM-X). Measurement and simulation results obtained in the batch experiments, spiked with the diclofenac and carbamazepine content of preclarified municipal wastewater shows comparably high biotransformation rates in the presence of growth substrates. Forward dynamic simulations were performed using full-scale data obtained from Bekkelaget WWTP (Oslo, Norway) to evaluate the model and to estimate the level of re-transformable xenobiotics present in the influent. The results obtained in this study demonstrate that xenobiotic loading conditions can significantly influence the removal capacity of WWTPs. We show that the trace chemical retransformation in upstream sewer pipes can introduce considerable error in assessing the removal efficiency of a WWTP, based only on parent compound concentration measurements. The combination of our data with those from the literature shows that solids retention time (SRT) can enhance the biotransformation of diclofenac, which was not the case for carbamazepine. Model approximation of the xenobiotic concentration, detected in the solid phase, suggest that between approximately 1% and 16% of the total solid carbamazepine and diclofenac concentrations, respectively, is due to sorption-the remainder being non-bioavailable and sequestered. We demonstrate the effectiveness of the model's predictive power over conventional tools in a statistical analysis, performed at four levels of structural complexity. To assess WWTP retrofitting needs to remove xenobiotic trace chemicals, we suggest using mechanistic models, e.g., ASM-X, in regional risk assessments. For preliminary evaluations, we present operating charts that can be used to estimate average xenobiotic removal rates in WWTPs as a function of SRT and the xenobiotics mass loads normalised to design treatment capacity.
- Published
- 2012
34. Analysis and Interpretation of Specific Ethanol Metabolites, Ethyl Sulfate, and Ethyl Glucuronide in Sewage Effluent for the Quantitative Measurement of Regional Alcohol Consumption
- Author
-
Jørg Mørland, Katherine Langford, Kevin V. Thomas, and Malcolm J. Reid
- Subjects
Chromatography ,Ethanol ,Chemistry ,business.industry ,Medicine (miscellaneous) ,Sewage ,Alcohol ,Urine ,Toxicology ,Ethyl sulfate ,Psychiatry and Mental health ,chemistry.chemical_compound ,Ethyl glucuronide ,Ingestion ,business ,Effluent - Abstract
Background: The quantitative measurement of urinary metabolites in sewage streams and the subsequent estimation of consumption rates of the parent compounds have previously been demonstrated for pharmaceuticals and narcotics. Ethyl sulfate and ethyl glucuronide are excreted in urine following the ingestion of alcohol, and are useful biomarkers for the identification of acute alcohol consumption. This study reports a novel ion-exchange-mediated chromatographic method for the quantitative measurement of ethyl sulfate and ethyl glucuronide in sewage effluent, and presents a novel calculation method for the purposes of relating the resulting sewage concentrations with rates of alcohol consumption in the region. Methods: A total of 100 sewage samples covering a 25-day period were collected from a treatment plant servicing approximately 500,000 people, and analyzed for levels of ethyl sulfate and ethyl glucuronide. The resulting data were then used to estimate combined alcohol consumption rates for the region, and the results were compared with alcohol related sales statistics for the same region. Results: Ethyl glucuronide was found to be unstable in sewage effluent. Ethyl sulfate was stable and measurable in all samples at concentrations ranging from 16 to 246nM. The highest concentrations of the alcohol biomarker were observed during weekend periods. Sixty one percent of the total mass of ethyl sulfate in sewage effluent corresponds to alcohol consumption on Friday and Saturday. Sales statistics for alcohol show that consumption in the region is approximately 6,750kg/d. The quantity of ethyl sulfate passing through the sewage system is consistent with consumption of 4,900 to 7,800kg/d. Conclusions: Sewage epidemiology assessments of ethyl sulfate can provide accurate estimates of community alcohol consumption, and detailed examination of the kinetics of this biomarker in sewage streams can also identify time-dependent trends in alcohol consumption patterns.
- Published
- 2011
- Full Text
- View/download PDF
35. Quantitative assessment of time dependent drug-use trends by the analysis of drugs and related metabolites in raw sewage
- Author
-
Jørg Mørland, Kevin V. Thomas, Malcolm J. Reid, and Katherine Langford
- Subjects
Pharmacology ,Consumption (economics) ,Evening ,Prescription Drugs ,Time Factors ,Sewage ,business.industry ,Names of the days of the week ,Illicit Drugs ,Solid Phase Extraction ,Toxicology ,Dependent drug ,Substance Abuse Detection ,Psychiatry and Mental health ,Environmental health ,Quantitative assessment ,Drug consumption ,Medicine ,Humans ,Pharmacology (medical) ,Cocaine metabolites ,business ,Water Pollutants, Chemical ,Half-Life - Abstract
Background : Accurate and timely information on the scale and dynamics of drug consumption is important for assessing the needs of law enforcement and public health services in a community. Aims : This paper presents a detailed examination of a comprehensive sewage-sampling campaign for the purposes of increasing an understanding of the dynamics of drug-flows in sewage streams, and developing new methodology by which this technique can support traditional drug-use surveys. Methods : A total of 104 sewage samples were collected from a treatment plant servicing approximately 500 000 people and analysed for levels of methamphetamine, cocaine and cocaine metabolites. Careful examination of the kinetics of drug-flow profiles was then performed in order to identify trends or patterns of use within the community. Results : Results were validated against identical measurements of pharmaceutical reference compounds. Consumption profiles for cocaine and methamphetamine were found to differ in terms of frequency and timing of use. The majority of cocaine consumption occurs during the evening hours and 45% of consumption of this drug occurs in weekend periods. The flow of methamphetamine in the sewage system appears more evenly spread throughout the week. Conclusions : This result is consistent with both an extended excretion half-life and a pattern of use that is more evenly balanced across all days of the week. Comprehensive investigation in to the scale and kinetics of drug flow in a sewage stream can therefore provide valuable information, not only in terms of the volume of drug consumed, but also in terms of identifying differing usage-patterns over daily and weekly time-scales.
- Published
- 2011
36. Input of selected human pharmaceutical metabolites into the Norwegian aquatic environment
- Author
-
Katherine Langford and Kevin V. Thomas
- Subjects
Geologic Sediments ,Chromatography ,Sewage ,Chemistry ,Norway ,Public Health, Environmental and Occupational Health ,General Medicine ,Carbamazepine ,Management, Monitoring, Policy and Law ,Waste Disposal, Fluid ,Diclofenac ,Wastewater ,Pharmaceutical Preparations ,Rivers ,Simvastatin ,Environmental chemistry ,medicine ,Sewage treatment ,Cities ,Effluent ,Surface water ,Water Pollutants, Chemical ,medicine.drug ,Waste disposal ,Environmental Monitoring - Abstract
The occurrence of the metabolites of five human pharmaceuticals was investigated in treated wastewater, surface waters and sediments. Metabolites of carbamazepine (carbamazepine epoxide), diclofenac (4'- and 5-hydroxy diclofenac) and atorvastatin (o- and p-hydroxy atorvastatin) were typically detected in flow proportional 24 h composite samples of wastewater effluent collected from the Norwegian cities of Oslo and Tromsø at higher concentrations than the parent pharmaceutical. The concentrations determined in discharged effluent were as high as 3700 ng L(-1) for 5-hydroxy diclofenac. The overall mean concentration of metabolites being typically higher in the primary treated effluent from the city of Tromsø compared to the tertiary treatment performed on the Oslo effluent. Metabolites of carbamazepine (carbamazepine-10,11-epoxide), metoprolol (α-hydroxy metoprolol) and simvastatin (hydroxy simvastatin) were detected in surface water samples collected from Oslofjord at concentrations of up to 108 ng L(-1), whilst α-hydroxy metoprolol and simvastatin hydroxy carboxylic acid were also detected in sediments at low ng L(-1) concentrations. These screening data show that the metabolites of selected pharmaceuticals are being discharged into the Norwegian coastal environment and that certain metabolites occur in marine surface waters and sediments.
- Published
- 2010
37. The BIOZO process--a biofilm system combined with ozonation: occurrence of xenobiotic organic micro-pollutants in and removal of polycyclic aromatic hydrocarbons and nitrogen from landfill leachate
- Author
-
Antonio Lopez, Helge Liltved, Christian Vogelsang, Benedek G. Plósz, Harald Heiaas, Katherine Langford, and Kenneth Macrae
- Subjects
Environmental Engineering ,Ozone ,Chromatography, Gas ,Nitrogen ,chemistry.chemical_element ,Pilot Projects ,Mass Spectrometry ,chemistry.chemical_compound ,Bioreactors ,Nitrate ,Bioreactor ,Humans ,Leachate ,Polycyclic Aromatic Hydrocarbons ,Water Science and Technology ,Pollutant ,Equipment Design ,Biodegradation ,chemistry ,Environmental chemistry ,Biofilms ,Xenobiotic ,Water Pollutants, Chemical ,Mutagens - Abstract
We present an assessment of xenobiotic organic micro-pollutants (XOM) occurrence and removal of polycyclic aromatic hydrocarbons (PAHs) in a novel biofilm system combined with ozonation, the BIOZO concept, treating partly stabilised landfill leachate. A novel, staged moving-bed biofilm reactor (SMBBR) design was implemented in laboratory- and pilot-scale, and the PAHs removal efficiency of controlled ozonation was assessed installing the ozonation step in the nitrate recirculation line (Position 1) or between the pre-anoxic and aerobic zones (Position 2). COD removal in a laboratory- and in a pilot-scale SMBBR system with and without ozonation is additionally addressed. Results obtained in a screening study (GC-ToF-MS) were used to compile a priority list of XOMs in leachate based on relative occurrence, showing PAHs as the predominant fraction. Biological treatment is shown to be an effective means to remove PAHs detected in the aqueous phase. PAH removal takes in most part place in the pre-anoxic zone, thereby decreasing toxicity exhibited by PAH on autotrophic nitrifier bacteria in the aerobic zone. Ozonation installed in Position 2 is shown to be superior over Position I in terms of COD, PAH and nitrogen removal efficiencies. We additionally demonstrate the potential of intermittent sludge ozonation as a means to decrease PAH concentrations in sludge wasted and to improve nitrogen removal in the BIOZO system.
- Published
- 2010
38. Bioconcentration of the intense sweetener sucralose in a multitrophic battery of aquatic organisms
- Author
-
Knut Erik Tollefsen, Katherine Langford, and Adam Lillicrap
- Subjects
Sucralose ,Aquatic Organisms ,Sucrose ,biology ,Health, Toxicology and Mutagenesis ,Daphnia magna ,Bioconcentration ,Biota ,Fresh Water ,biology.organism_classification ,Food web ,chemistry.chemical_compound ,Algae ,chemistry ,Daphnia ,Chlorophyta ,Bioaccumulation ,Environmental chemistry ,Sweetening Agents ,Environmental Chemistry ,Animals ,Steady state (chemistry) ,Water Pollutants, Chemical ,Zebrafish - Abstract
Reports of the intense (artificial) sweetener sucralose (1,6-dichloro-1,6-dideoxy-β-D-fructo-furanosyl 4-chloro-4-deoxy-α-D-galactopyranoside) in various environmental compartments have led to speculations about biological effects in nontarget species living in areas receiving discharges from anthropogenic activities. We have, as the first step in the risk assessment of this compound, conducted bioaccumulation studies in the freshwater alga Pseudokirchneriella subcapitata, the crustacean Daphnia magna, and zebrafish (Danio rerio). The freshwater algae and the daphnid tests were performed using a 48-h static exposure system, whereas the zebrafish test was performed using a 48-h semi static exposure system followed by 48 h flow-through of clean water for the depuration phase. All three studies were conducted with two exposure concentrations (10 and 100 mg/L), and the concentrations of sucralose in water and biota were verified by liquid chromatography/mass spectrometry. The studies showed that uptake of sucralose was assumed to achieve a steady state within the first 48 h, and the bioconcentration factor at the assumed steady state (BCFSS) was calculated to be less than 1 for algae and between 1.6 to 2.2 for the daphnids. The fish BCFSS, assumed to occur between 24 to 48 hours, were calculated to be less than 1 for both concentrations tested. A first-order one-compartment (uptake phase) and a first-order two-compartment (elimination phase) model characterized the uptake and depuration kinetics in zebrafish (k1 = 0.027–0.038/h and k2 = 0.206–0.222/h, t95 = 13.5 to 14.6 h, t50 = 3.1 to 3.3 h, and BCFkinetic = 0.4 to 0.9). The current study shows that sucralose does not bioaccumulate in aquatic organisms from different tiers of the food web, and that the BCF's obtained were considerably lower than the criteria set to identify persistent, bioaccumulative, and toxic substances (i.e., BCF ≥ 2,000). Environ. Toxicol. Chem. 2011; 30:673–681. © 2011 SETAC
- Published
- 2010
39. Effect-directed identification of naphthenic acids as important in vitro xeno-estrogens and anti-androgens in North sea offshore produced water discharges
- Author
-
Katherine Langford, Knut Erik Tollefsen, Andrew Smith, Karina Petersen, and Kevin V. Thomas
- Subjects
Agonist ,Time Factors ,medicine.drug_class ,Carboxylic Acids ,Estrogen receptor ,Saccharomyces cerevisiae ,Mass Spectrometry ,chemistry.chemical_compound ,Naphthenic acid ,medicine ,Androgen Receptor Antagonists ,Environmental Chemistry ,Seawater ,Receptor ,Chromatography, High Pressure Liquid ,Androgen Antagonists ,Dihydrotestosterone ,Estrogens ,General Chemistry ,Ligand (biochemistry) ,Produced water ,Androgen receptor ,chemistry ,Receptors, Estrogen ,Estrogen ,Environmental chemistry ,North Sea ,Water Pollutants, Chemical - Abstract
Produced water from offshore oil production platforms represents the largest direct discharge of effluent into the offshore environment. Produced water effluents contain a complex mixture of substances which are known to bind to the estrogen receptor (ER) and antagonize the androgen receptor (AR). Short-chain petrogenic alkylphenols have been identified as responsible for around 35% of the ER agonist activity measured in vitro while the compounds responsible for antagonizing the androgen receptor are unknown. For the first time we report that petrogenic naphthenic acids are weak ER agonists that account for much of the 65% of the "unknown" ER agonist potency in North Sea produced waters while also disrupting the binding of AR agonists to the AR ligand receptor. We also report other known petrogenic components such as polycyclic aromatic hydrocarbons (PAHs) and alkylphenols as environmental AR antagonists. Our investigation shows that these petrogenic components are responsible for the majority of the ER and AR receptor mediated activity in produced waters. This hypothesis is supported by data from an effects-directed analysis of produced water using normal-phase high-performance liquid chromatography (HPLC) fractionation in combination with the yeast estrogen and androgen assays as well as androgen receptor binding assays of commercially available mixtures of naphthenic acids.
- Published
- 2009
40. Second interlaboratory exercise on non-steroidal anti-inflammatory drug analysis in environmental aqueous samples
- Author
-
Tina Kosjek, Damià Barceló, L. Mainero Rocca, Marinella Farré, Katherine Langford, Jelena Radjenovic, D. Tsipi, L. F. de Alencastro, José Benito Quintana, Hélène Budzinski, Ester Heath, Ruth J. F. Loos, O. Gans, Mira Petrovic, and Sara Castiglioni
- Subjects
Diclofenac ,Sample (statistics) ,Ibuprofen ,River water ,Chemistry Techniques, Analytical ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,Water Purification ,Naproxen ,Tap water ,Waste-Water ,Filter material ,Chromatography ,Chemistry ,Non-steroidal anti-inflammatory drugs (NSAIDs) ,Tests ,Anti-Inflammatory Agents, Non-Steroidal ,Interlaboratory ,Reproducibility of Results ,Chromatography-Mass Spectrometry ,Non steroidal anti inflammatory ,Ketoprofen ,Biochemical engineering ,Gas chromatography–mass spectrometry ,Drug analysis ,Pharmaceutical Residues ,Filtration ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
Several interlaboratory exercises were organised within the framework of European FP6 project NORMAN. Among others, non-steroidal anti-inflammatory drugs were investigated in different aqueous samples in two sequential ring studies. The aim of both studies was to evaluate the state-of-art in Europe and to determine possible sources of variation, while also attempting to diminish them. In the present paper we discuss the results of the 2nd Interlaboratory study, while the results of 1st round were presented before. The main scope of the 1st exercise organised within NORMAN project was to assess the laboratory proficiency regardless of the analytical method applied, to evaluate the stability of the target compounds during sample storage, and to define possible sources of variation during sample shipment, storage and analysis. In the 2nd round we primarily aimed to diminish these sources of variation by applying two predetermined analytical protocols based on liquid chromatography–mass spectrometry or gas chromatography–mass spectrometry. The two analytical protocols were compared in terms of their ability to determine individual analytes in matrices of different complexity, i.e. tap water, river water and wastewater. Furthermore, the 2nd exercise addressed also the filtration and compared the influence of different filter material categories on the analysis of non-steroidal anti-inflammatory drugs. Results presented herein evaluate laboratory performance using z-score, bias, proximity and Youden plots. Overall, the laboratory performances were found to be satisfactory for determining NSAIDs in aqueous samples. The two analytical protocols, LC–MS and GC–MS, are assessed according to their sensitivity and measurement uncertainty, where the GC–MS proved superior for the analysis of Ibuprofen, Ketoprofen and Naproxen in matrices with higher complexity. Finally, neither the filtration itself, nor the filter materials were shown to significantly affect the determination of NSAIDs., This work has been supported by EU FP6 project NORMAN (contract no.: 018486) and Ad Futura grant (523-026/2006). Authors wish to thank Mrs. Silva Perko for her valuable advices and support in sample preparation.
- Published
- 2009
41. Cellular energy allocation in Hediste diversicolor exposed to sediment contaminants
- Author
-
Katherine Langford, Eirin Sva Stomperudhaugen, Ketil Hylland, Wim De Coen, Nina Helene Hanssen Øverås, and Roel Smolders
- Subjects
Geologic Sediments ,Time Factors ,Health, Toxicology and Mutagenesis ,Movement ,Biomass ,Toxicology ,Perfluorononanoic acid ,chemistry.chemical_compound ,Animals ,Biology ,Polychaete ,Fluorocarbons ,biology ,Sediment ,Polychaeta ,Environmental Exposure ,Contamination ,biology.organism_classification ,chemistry ,Environmental chemistry ,Hediste diversicolor ,Tributyltin ,Cellular energy ,Trialkyltin Compounds ,Energy Metabolism ,Water Pollutants, Chemical - Abstract
Environmental contaminants released into water tend to accumulate in sediment, leading to exposure for sediment-dwelling organisms. This study aimed to clarify whether chronic (56 d) exposure to a mixture of environmentally relevant concentrations of contaminants (tributyltin [TBT] and perfluorononanoic acid [PFNA]) spiked in clean sediment would affect the sediment-dwelling polychaete Hediste diversicolor. Endpoints were burial time, biomass change, and cellular energy allocation (CEA). Sediments were spiked with these two contaminants to produce different levels of contamination. Chemical analyses of the sediment following the exposure indicated that the spiking procedure was only partially successful and treatments were grouped into four categories according to contaminant concentrations: "background," "low," "moderate," and "high." No significant differences were found between treatments with respect to burial time, biomass change, or energy storage fractions (proteins, lipids, carbohydrates) in the polychaetes. A significant increase in cellular respiration was found for polychaetes in "moderate" and "high" treatment groups compared to the "background" treatment group. This resulted in significantly lower cellular energy allocation values for "moderate" and "high" treatment groups compared to "background." Although the effects were not marked, the results show that sediment-dwelling organisms may be affected following chronic exposure to environmental contaminants. There is a need to clarify whether chronic exposures exert a negative effect on sediment-dwelling organisms.
- Published
- 2009
42. The Analysis of Antifouling Paint Biocides in Water, Sediment and Biota
- Author
-
Kevin V. Thomas and Katherine Langford
- Subjects
Biofouling ,Biocide ,Aquatic ecosystem ,Environmental chemistry ,Environmental engineering ,Environmental science ,Water sediment ,Biota ,Irgarol 1051 - Abstract
Alternative antifouling biocides to TBT were first detected in environmental surface waters in the early 1990s (Readman et al. 1993). Irgarol 1051 was first detected in the surface waters of marinas on the Cote d'Azur, France at concentrations of up to 1,700 ng l-1 (Readman et al. 1993) and in subsequent years the occurrence of Irgarol 1051 was reported in both fresh and marine waters (Scarlett et al. 1999; Thomas et al. 2000; Martinez et al. 2001; Lamoree et al. 2002) These reports established that the alternative antifouling biocides being used to replace the restricted TBT could also be accumulating in the environment and possibly posing a risk to aquatic habitats. Following Irgarol 1051, a number of other compounds were also used as biocidal additives to antifouling paints and methods have been developed to determine their occurrence in environmental waters (Thomas 1998; Piedra et al. 2000; Thomas et al. 2001). The early studies used GC-MS analysis of water extracts to analyse Irgarol 1051 alone; however, as the field developed, multi-residue LC-MS or LC-tandem MS techniques followed that allowed for the simultaneous analysis of the most commonly used biocides and their metabolites (Thomas 1998). However, for certain biocides (e.g. zinc pyrithione) specific methods are predominantly used due to the intrinsic physico-chemical properties that make it a difficult compound to quantitatively analyse (Thomas 1999).
- Published
- 2009
- Full Text
- View/download PDF
43. Inputs of chemicals from recreational activities into the Norwegian coastal zone
- Author
-
Katherine Langford and Kevin V. Thomas
- Subjects
Biocide ,geography ,geography.geographical_feature_category ,Molecular Structure ,Norway ,Aquatic ecosystem ,Oceans and Seas ,fungi ,Public Health, Environmental and Occupational Health ,Environmental engineering ,Fjord ,General Medicine ,Management, Monitoring, Policy and Law ,Contamination ,Wastewater ,Environmental chemistry ,Water Pollution, Chemical ,Environmental science ,Recreation ,Sewage treatment ,Seawater ,Seasons ,Effluent ,Insect repellent ,Water Pollutants, Chemical - Abstract
Wastewater treatment works effluent is often considered to be one of the most important point sources of a wide range of anthropogenic contaminants to aquatic systems, however, this paper discusses other potential sources. With the aim of establishing the important sources of UV filters, insect repellent and biocides to the aquatic environment, samples were collected from sites with direct (bathing areas and marinas) and indirect (sites receiving wastewater effluent) human influences. Sunscreens containing UV filters are used in large volumes during the summer months and often applied shortly before a person enters the water for swimming activities. The results presented here demonstrate that washing directly from the skin is an important point source of 4 UV filters to the Oslofjord. The insect repellent, diethyl toluamide, was also measured and it was concluded that washing from the skin was not such an important point source into the fjord. Concentrations of the biocide Irgarol 1051 were also measured and were elevated in the small boat marina and surrounding enclosed area. This work demonstrates that mans recreational water-based activities are a diffuse source of some contaminants into coastal and fjord environments and this study provides an initial assessment of the levels being released.
- Published
- 2008
44. Source to sink tracking of selected human pharmaceuticals from two Oslo city hospitals and a wastewater treatment works
- Author
-
Martin Schlabach, Christian Dye, Katherine Langford, and Kevin V. Thomas
- Subjects
Meclocycline ,Anti-Inflammatory Agents ,Antineoplastic Agents ,Oxytetracycline ,Management, Monitoring, Policy and Law ,Waste Disposal, Fluid ,Hospitals, Urban ,medicine ,Humans ,Effluent ,Analgesics ,Chromatography ,Demeclocycline ,Chemistry ,Norway ,Sulfamethoxazole ,digestive, oral, and skin physiology ,Public Health, Environmental and Occupational Health ,Estrogens ,General Medicine ,Trimethoprim ,Anti-Bacterial Agents ,Pharmaceutical Preparations ,Environmental chemistry ,Housing ,Sewage treatment ,Water Pollutants, Chemical ,medicine.drug ,Waste disposal - Abstract
The occurrence of twenty pharmaceutical compounds was quantitatively determined in effluents from two major Oslo city hospitals, Rikshospitalet and Ulleval, along with influent, sludge and final effluent from the city's VEAS wastewater treatment works (WTW). Composite hospital effluents were collected over a twelve week period and were showed to contain paracetamol, metoprolol, diclofenac, ibuprofen, 17beta-Estradiol, estriol, estrone, oxytetracycline, tetracycline, doxycycline, chlorotetracycline, demeclocycline, trimethoprim, ciprofloxacin, sulfamethoxazole, cyclophosphamide and ifosfamide. Three pharmaceuticals were not detected above the limit of detection; cefuroxime, 17alpha-ethinylestradiol and meclocycline. Composite influent, sludge and effluent samples were collected from VEAS WTW over a seven week period. The influent into VEAS WTW contained all of the same selected substances detected in the hospital effluents, except for oxytetracycline, chlorotetracycline, demeclocycline, cyclophosphamide and ifosfamide. The percentage of pharmaceuticals entering the works from the hospitals was
- Published
- 2007
45. Chapter 3.1 Occurrence of pharmaceuticals in the aqueous environment
- Author
-
Kevin V. Thomas and Katherine Langford
- Subjects
Wastewater ,Aquatic environment ,Environmental chemistry ,fungi ,Environmental science ,Sewage treatment ,Water treatment ,Contamination ,complex mixtures ,Effluent ,Groundwater ,Aquatic organisms - Abstract
Publisher Summary The occurrence of pharmaceutical substances in the aquatic environment serves as a reminder that not only those substances traditionally targeted, or those that occur on priority lists for monitoring programmes, contaminate the aquatic environment. Uptake of pharmaceuticals by aquatic organisms is an important consequence of elevated pharmaceutical concentrations in receiving waters such as effluent dominated rivers and streams. Groundwater can be contaminated from a number of sources (for example, historic contamination from sites of production, runoff from agricultural land, landfill, and wastewater effluent). The introduction of pharmaceuticals to the aquatic environment via wastewater treatment and effluent discharge is dependent on drug use, pharmokinetic and physicochemical properties of the drug, and on the water treatment processes involved. There are occurrence data for a wide range of pharmaceutical compounds, at the same time, in certain countries, national monitoring surveys are performed. These data show that many of the targeted pharmaceuticals occur in aqueous samples and that wastewater and treated wastewater is the principle source of human pharmaceutical compounds to the environment. The occurrence of elevated concentrations of pharmaceutical compounds in the environment is of concern. However, occurrence alone does not indicate that they are causing any harmful effects or if they have the potential to harm the environment.
- Published
- 2007
- Full Text
- View/download PDF
46. Effects-directed analysis of organic toxicants in wastewater effluent from Zagreb, Croatia
- Author
-
Knut Erik Tollefsen, Katherine Langford, Merete Grung, Kevin V. Thomas, Rainer Lichtenthaler, and Marijan Ahel
- Subjects
Environmental Engineering ,Cell Survival ,Croatia ,Trout ,Health, Toxicology and Mutagenesis ,Gas Chromatography-Mass Spectrometry ,Mass Spectrometry ,chemistry.chemical_compound ,Vitellogenin ,Vitellogenins ,Cytochrome P-450 CYP1A1 ,Environmental Chemistry ,Bioassay ,Animals ,Solid phase extraction ,Effluent ,Cells, Cultured ,Chromatography, High Pressure Liquid ,Methylparaben ,biology ,Molecular Structure ,Sewage ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Pollution ,chemistry ,Wastewater ,Environmental chemistry ,Toxicity ,biology.protein ,Hepatocytes ,Gas chromatography–mass spectrometry ,toxicity identification evaluation ,wastewater ,estrogenicity ,EROD ,metabolic inhibition ,cytotoxicity ,bioassays ,Water Pollutants, Chemical ,Chromatography, Liquid ,Environmental Monitoring - Abstract
The organic toxicants present in the effluent of the main sewer of the city of Zagreb, Croatia were isolated and identified through the use of effects-directed characterisation techniques. At the time of investigation, the wastewater effluent received no treatment and was comprised of a mixture of effluent from domestic and industrial sources. The organic load of the wastewater was isolated by solid phase extraction and toxicity profiles obtained using reverse-phase HPLC. All procedures were evaluated through the analysis of a series of reference compounds of widely differing polarity. Toxicity profiles for EROD activity (CYP1A induction), vitellogenin induction (estrogenic activity), cytotoxicity (membrane stability and metabolic inhibition) were obtained using a rainbow trout (Oncorhynchus mykiss) primary hepatocyte bioassay. The suite of bioassays showed biological responses after exposure to the raw extracts for all the endpoints tested. However, a combination of mixture toxicity and cytotoxicity in the complex raw extract had some masking effect on the sub-lethal responses of vitellogenin and EROD induction. Bioassay testing of the fine fractions obtained by HPLC produced a range of endpoint-specific toxicity profiles for each sample. A number of compounds were identified by the use of GC-MS and LC-MS/MS as responsible for the observed effects. The steroid estrogens 17 beta-estradiol and estriol were identified by LC-MS/MS as estrogen receptor agonists in two of the estrogenic fractions. In addition, GC-MS analysis identified different alkylphenols, benzophenone and methylparaben which also contributed to the estrogenic activity of the sample. Polycyclic aromatic hydrocarbons (PAHs), alkyl substituted PAHs, nitro-polycyclic aromatic compounds (nitro-PACs), carbazoles and alkyl substituted carbazoles and other known CYP1A inducers were identified by GC-MS analysis as responsible for some of the observed EROD activity. Some active compounds remain unidentified.
- Published
- 2006
47. The impact of process variables on the removal of PBDEs and NPEOs during simulated activated sludge treatment
- Author
-
Mark D. Scrimshaw, John N. Lester, and Katherine Langford
- Subjects
Pollution ,endocrine system ,Hydraulic retention time ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,Polybrominated Biphenyls ,Endocrine Disruptors ,Toxicology ,Waste Disposal, Fluid ,Polyethylene Glycols ,chemistry.chemical_compound ,Surface-Active Agents ,Polybrominated diphenyl ethers ,Effluent ,media_common ,Flame Retardants ,Sewage ,Chemistry ,Phenyl Ethers ,General Medicine ,Nonylphenol ,Activated sludge ,Biodegradation, Environmental ,Wastewater ,Environmental chemistry ,Sewage treatment ,Water Pollutants, Chemical - Abstract
This work illustrates that the removal of some endocrine-disrupting compounds from sewage treatment works effluent is dependent on parameters such as sludge age, influent concentrations, concentrations of co-pollutants and hydraulic retention time as well as physicochemical properties of the compound. Greater nonylphenol polyethoxylates (NPEO) and polybrominated diphenyl ether (PBDE) removal was observed at a higher sludge age, and it appeared that the enzymes required for NPEO degradation were already present. NPEO degradation was reduced in the presence of the more hydrophobic PBDE compounds as sorption of PBDEs occurred, rapidly reducing available sorption sites for NPEOs. The more hydrophobic NP and PBDEs demonstrated little degradation in comparison to longer-chain NPEO compounds. From this research, it is apparent that the principal environmental risk of PBDE contamination after wastewater treatment is via sludge-disposal routes. Treatment of wastewater containing NPEO surfactants poses environmental risks via two routes: some nonylphenolic compounds may pass through into receiving waters and degradation products such as nonylphenol and short-chain ethoxylate compounds will enter the environment via sludge disposal.
- Published
- 2006
48. Analytical methods for the determination of alkylphenolic surfactants and polybrominated diphenyl ethers in wastewaters and sewage sludges. I a review of methodologies
- Author
-
John N. Lester, Katherine Langford, and Mark D. Scrimshaw
- Subjects
Alkylphenol ,Polybrominated Biphenyls ,Endocrine System ,Waste Disposal, Fluid ,Chemistry Techniques, Analytical ,Gas Chromatography-Mass Spectrometry ,chemistry.chemical_compound ,Surface-Active Agents ,Polybrominated diphenyl ethers ,Phenols ,Environmental Chemistry ,Waste Management and Disposal ,Water Science and Technology ,Flame Retardants ,Diphenyl ether ,General Medicine ,chemistry ,Endocrine disruptor ,Environmental chemistry ,Sewage treatment ,Gas chromatography–mass spectrometry ,Sludge ,Water Pollutants, Chemical ,Waste disposal ,Chromatography, Liquid ,Environmental Monitoring ,Ethers - Abstract
Alkylphenolic surfactants (alkylphenol polyethoxylates) and the polybrominated diphenyl ether flame retardants are important environmental contaminants and have been implicated as endocrine disrupters. Both groups of compounds have come under increasing scrutiny from legislators and there are proposals to curb their use. However, these compounds continue to enter the environment and there is a need to determine their occurrence, fate and behaviour throughout the hydrosphere and in wastewater treatment processes to determine mass fluxes and sources. This paper reviews analytical methods for their determination in the aqueous and solid (sediment / sludge) phase. Extraction, cleanup and quantification by gas and liquid chromatographic (GC and LC) techniques linked to mass spectrometric (MS) detectors are considered. The literature indicates that for the alkylphenols research papers favour the use of LC/MS which is more amenable to determination of more highly ethoxylated oligomers, however, standard methods focus on GC/MS and the less ethoxylated oligomers and parent alkylphenols. The use of GC with negative chemical ionisation MS techniques predominates for the analysis of polybrominated diphenyl ethers.
- Published
- 2004
49. The partitioning of alkylphenolic surfactants and polybrominated diphenyl ether flame retardants in activated sludge batch tests
- Author
-
Katherine Langford, Jason W. Birkett, John N. Lester, and Mark D. Scrimshaw
- Subjects
Environmental Engineering ,Health, Toxicology and Mutagenesis ,Polybrominated Biphenyls ,Risk Assessment ,Waste Disposal, Fluid ,chemistry.chemical_compound ,Surface-Active Agents ,Polybrominated diphenyl ethers ,Environmental Chemistry ,Organic chemistry ,Freundlich equation ,Organic Chemicals ,Flame Retardants ,Sewage ,Chemistry ,Diphenyl ether ,Public Health, Environmental and Occupational Health ,Sorption ,General Medicine ,General Chemistry ,Pollution ,Nonylphenol ,Activated sludge ,Wastewater ,Solubility ,Environmental chemistry ,Sewage treatment ,Adsorption ,Ethers - Abstract
Polybrominated diphenyl ethers and nonylphenol polyethoxylates have been reported to be estrogenic and may enter the aquatic environment through the discharge of treated sewage effluent. Therefore, their fate during wastewater treatment processes is an important factor in determining their environmental impact. Batch tests with activated sludge from a Husmann apparatus were used to determine the effects of physico-chemical properties and sludge characteristics on the partitioning of polybrominated diphenyl ether flame retardants and nonylphenol polyethoxylate surfactants during biological wastewater treatment. Hydrophobic compounds, those with high log Kow values, were sorbed more rapidly and to a greater extent to the solid phase than more soluble compounds. For these hydrophobic compounds sorption may become an increasingly important removal mechanism as sludge age and therefore solids content increase. The initial rate of partitioning was greatest for the most hydrophobic compounds but all rates diminished with time as a result of progressive saturation of sorbent binding sites, a reduction of sorbate availability and as a consequence of the system reaching equilibrium. The sorption of polybrominated diphenyl ethers fit Freundlich adsorption isotherms demonstrating generally increasing adsorption capacity and efficiency with increasing hydrophobic nature. A correlation between increasing log Kow and increasing organic matter content was also observed for both polybrominated diphenyl ethers and nonylphenol polyethoxylates indicating the organic content of mixed liquor will also be influential in removing compounds during wastewater treatment.
- Published
- 2004
50. Fate and Behavior of Endocrine Disrupters in Wastewater Treatment Processes
- Author
-
Katherine Langford and John N. Lester
- Subjects
Chemistry ,Environmental chemistry ,Endocrine system ,Sewage treatment - Published
- 2002
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.