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The application of sewage sludge (SS) in agriculture, as an alternative to manufactured fertilizers, is current practice worldwide. However, as wastewater is collected from households, industries, and hospitals, the resulting sludge could contaminate land with creeping levels of pharmaceuticals, pesticides, heavy metals, polycyclic aromatic hydrocarbons, and microplastics, among others. Thus, the sustainable management of SS requires the development of selective methods for the identification and quantification of pollutants, preventing ecological and/or health risks. This study presents a thorough evaluation of emerging and priority micropollutants in SS, through the lens of environmental insights, by developing and implementing an integrated analytical approach. A quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method, coupled with gas chromatography and liquid chromatography, was optimized for the determination of 42 organic compounds. These include organophosphorus pesticides, organochlorine pesticides, pyrethroid pesticides, organophosphate ester flame retardants, polybrominated diphenyl ethers, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons. The optimization of the dispersive-solid phase for clean-up, combined with the optimization of chromatographic parameters, ensured improved sensitivity. Method validation included assessments for recovery, reproducibility, limit of detection (LOD), and limit of quantification (LOQ). Recoveries ranged from 59.5 to 117%, while LODs ranged from 0.00700 to 0.271 µg g-1. Application of the method to seven SS samples from Portuguese wastewater treatment plants revealed the presence of sixteen compounds, including persistent organic pollutants. The quantification of α-endosulfan, an organochlorine pesticide, was consistently observed in all samples, with concentrations ranging from 0.110 to 0.571 µg g-1. Furthermore, the study encompasses the analysis of agronomic parameters, as well as the mineral and metal content in SS samples. The study demonstrates that the levels of heavy metals comply with legal limits. By conducting a comprehensive investigation into the presence of micropollutants in SS, this study contributes to a deeper understanding of the environmental and sustainable implications associated with SS management. [ABSTRACT FROM AUTHOR]

Recovery of bioactive compounds from biowaste is gaining more and more interest in circular economy models. The oilseed cakes are usually insufficiently exploited by most technologies since they represent valuable matrices abundant in proteins, minerals, and phytochemicals, but their use is mostly limited to feed ingredients, fertilizers or biofuel production. This study was thus focused on the exploration of new valorization pathways of oilseed cakes by subcritical water, representing a safe and economic alternative in the creation of value chains. Pumpkin, hemp, and flax seed cakes were treated with subcritical water in nitrogen and carbon-dioxide atmospheres, as well as in nitrogen atmosphere with the addition of acid catalyst. The degradation of carbohydrate fraction was studied by quantifying sugars and sugar degradation products in the obtained extracts. The extracts obtained under different conditions were further compared chemically with respect to total phenols and flavonoids, as well as to the content of individual phenolic compounds. Furthermore, the effects of subcritical water treatment conditions on antioxidant, antiradical and cytotoxic properties of thus obtained extracts were defined and discussed. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous global pollutants that are lipophilic, bioaccumulative and can be both endocrine disruptors and carcinogens. In this study, we measured 18 PAHs among decapod shrimp samples (Palaemon spp.) collected during the spring and autumn from multiple locations along the Portuguese coastal, including local markets and aquaculture farms. ΣPAH concentrations in samples ranged from 3.14 to 320.48 ng/g (ww) with the highest value in this range detected in a sample provided from an aquaculture facility. Fifteen of the 18 scanned PAHs were present in shrimp samples. However, detectable concentrations (0.07 ng/g ww) of the carcinogenic benzo-a-pyrene occurred for a single sample only and approached method detection limits. No significant differences in shrimp ΣPAH concentrations were evident between the spring and autumn seasons. Target hazard quotient estimation suggested low probability of adverse health effects to consumers through consumption of shrimp from the study collection locations. [ABSTRACT FROM AUTHOR]

This study aimed the optimization of antioxidant activity, total phenolic compounds (TPC) and total carotenoids of Horned Melon fruit submitted to maceration extraction, using ethanol as solvent. Optimization was performed by Box–Behnken design on three levels and three variables: extraction temperature (25 °C, 55 °C, and 85 °C), extraction time (0.5, 2.0, and 3.5 h) and ethanol concentration (10%, 50%, and 90%). The optimal conditions to improve the carotenoids extraction was 55 °C, 1.5 h and 86% ethanol, whereas the antiradical/antioxidant activity (ABTS and FRAP assays) and TPC were enhanced at 45 °C for 2.0 h and 40% ethanol. The optimal antioxidant extract was characterized regarding the phenolic composition and in vitro neuroprotective activities. The phenolic composition revealed the presence of high amounts of gallic acid (11.7 ± 0.6 mg/100 g dw) and protocatechuic acid (7.69 ± 0.38 mg/100 g dw). However, this extract presented a weak activity against Monoamine oxidase A (11.8 ± 2.3% inhibition at 2.7 mg/mL) and did not display anti-cholinesterase activity at the maximum concentration tested (1.3 mg/mL). Maceration was an efficient extraction technique to recover polyphenols and carotenoids from Horned Melon fruit. The optimized model can be very useful for food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Three sampling campaigns were performed in the Lis River (Leiria, Portugal) in February of 2018, November of 2018, and May of 2019. River water and wastewater (influent and effluent) samples of two wastewater treatment plants were target of the study. A total of 25 samples were collected and 50 pesticides were monitored, including organochlorines, triazines, pyrethroids, and organophosphorus, among others. Most of the detected pesticides were insecticides and mainly organochlorines. Concentrations between 1.29 and 2134 ng/L were found. Aldrin, γ-HCH, and cypermethrin were detected in some samples in μg/L, being γ-HCH the pesticide most frequently detected with concentration in μg/L level. The pesticides with the highest detection frequency were (i) cypermethrin, HCB, methoxychlor, and ζ-HCH in river waters; (ii) isoproturon, cypermethrin, methoxychlor, pyrimethanil, γ-HCH, dieldrin, diuron, α-HCH, and α-endosulfan in effluents; and (iii) diuron and isoproturon in influents. The detection of the organochlorides and their degradation products is a consequence of their persistence in the environment, as their usage has long been prohibited in the European Union. Pesticides were grouped by their types in herbicides, insecticides, or fungicides and the detection and concentration for each type were discussed with the climatic conditions. Pesticide toxicity index was determined in the samples collected in the river. [ABSTRACT FROM AUTHOR]

Recently, the value of wood residues has received increasing attention due to the presence of pharmacologically active compounds. In the present study, apple bark was treated with subcritical water (SWE) with the aim of bioactivity determination and chemical analysis by GC–MS applying two different sample preparation protocols and by HPLC. Extracts were screened for their total antioxidant capacity by means of total phenolic (TPC) and flavonoid contents (TFC), ferric reducing antioxidant power (FRAP) and DPPH-radical scavenging activity (DPPH-RSA). Anti-microbial and anti-proliferative activities of the apple bark subcritical water extracts were also examined. Different lignin and cellulose degradation products were identified by GC–MS, as well as naturally present compounds. Identified compounds encompassed organic and fatty acids, alcohols, sugars, phenol, benzaldehyde, cinnamic acid, cinnamaldehyde and azulene derivatives, as well as other organic compounds. Phenolic profiles of apple bark extracts defined by HPLC–PDA analysis revealed that the main contributors were gallic acid (9.4 ± 0.5 mg/g DW) and catechin (8.3 ± 0.4 mg/g DW). The diversity of the extracts composition supports the fact that this medium is able to extract compounds of different polarities, simultaneously acting as catalyst and reactant. The characterized apple bark extracts demonstrated good antioxidant (TPC = 31.47 ± 1.86 mg GAE/g; TFC = 17.40 ± 1.89 mg EE/g; FRAP = 22.45 ± 2.22 mg AAE/g; DPPH-RSA = 22.57 ± 2.24 mg Trolox E/g DW), antimicrobial (MIC = 19.53–156.25 μg/mL) and anti-proliferative activity (IC50 = 19.88–47.44 μg/mL). The findings of this study showed that SWE can be used as an environmentally friendly and safe technique for the valorization of apple tree wood residues, applicable in food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

An electrochemical magnetic immunosensing strategy was developed for the determination of HER2-ECD, a breast cancer biomarker, and breast cancer cells in human serum. A sandwich assay was performed on carboxylic acid-functionalized magnetic beads (MBs) using a screen-printed carbon electrode (SPCE) as transducer surface. The affinity process was detected using electroactive labels; core/shell streptavidin-modified CdSe@ZnS Quantum Dots (QDs). Cd2+ ions, released from the QDs, were determined by differential pulse anodic stripping voltammetry (DPASV). An assay time of 90 min, with an actual hands-on time of about 20 min, a linear range between 0.50–50 ng·mL−1 of HER2-ECD and a limit of detection of 0.29 ng·mL−1 were achieved. Analysis of live breast cancer cells was also performed using the optimized assay. Breast cancer cell lines SK-BR-3 (a HER2-positive cell line), MDA-MB-231 (a HER2-negative cell line) and MCF-7 (a cell line with low HER2 expression) were tested. The selectivity of the assay towards SK-BR-3 cells was confirmed. A concentration-dependent signal that was 12.5× higher than the signal obtained for the HER2-negative cells (MDA-MB-231) and a limit of detection of 2 cells·mL−1 was obtained. [ABSTRACT FROM AUTHOR]

Histamine is an important biogenic amine because of its role in immune responses and the regulation of physiological functions. It is also used as a food freshness indicator, so its maximum concentration in fish is legally regulated. Although several robust and sensitive methods for histamine detection are already available, it continues to be a challenge to develop simple and portable devices that allow rapid histamine screening at any point of the fish production chain. Thus, in this work, a simple, miniaturized and low-cost sensor for histamine analysis was developed. The construction of the sensor only takes 30 min and consists of the immobilization of the enzyme diamine oxidase on the surface of a screen-printed carbon electrode by cross-linking. The quantification of histamine was achieved by chronoamperometry (+ 0.2V, 120 s) using hexacyanoferrate (III) as a redox mediator. This selective sensor provided a low limit of detection (0.97 mg L−1) and accurate and precise results and was successfully applied to the analysis of spiked tuna and mackerel extracts, obtaining recovery values of 99–100%. Moreover, the sensor shows good stability, maintaining 87.7% of its initial signal after 35 days. [ABSTRACT FROM AUTHOR]

Investigation during 11-month period was performed to study the presence of caffeine in the Lis River in Leiria Town in Portugal, and a monitoring during 9-month period was realized to check the contribution of the human pollution of two wastewater treatment plants (WWTPs) that discharge their effluents to the studied river. The samples were collected in five sampling points along the river and in two influents and two effluents of the studied WWTPs. Caffeine was detected in all ninety-one collected samples. The caffeine concentration ranged from 25.3 to 321 ng/L in the river samples, from 112 to 1927 ng/L in the WWTP effluents, and from 9478 to 83,901 ng/L in the WWTP influents. The highest concentration in the river was detected in the two sampling points located after the effluent discharge points and reached 315 and 321 ng/L. Risk assessment was performed for three trophic levels using the risk quotient calculation and revealed that caffeine do not cause toxic effect on Daphnia magna and on fish but could be possibly toxic to algae. The results proved that caffeine can be an effective indicator of human-born pollution. [ABSTRACT FROM AUTHOR]

This study describes the possibilities of valorising a waste stream that originates from apple wood by mapping the reducing capacity and phenolic profile from extracts derived from apple tree (Malus domestica). This study evaluated the efficiency of warm solvent extraction (WSE) and ultrasound-assisted extraction (UAE) techniques for extracting antioxidant phenolic compounds from the bark and core wood of an apple tree cultivated in the north-eastern part of Belgium. Furthermore, the influence of the pre-treatment technique, namely, fresh, oven-dried, and freeze-dried samples, respectively, on the yield of polyphenols was studied. Fresh bark extract obtained by UAE—the most efficient extraction technique—employing acetone 60% v/v contains the highest levels of phenolic compounds as well as the highest antioxidant activity. High-performance liquid chromatographic analysis shows that phloridzin is the major compound of the identified polyphenol markers present in bark and core wood extracts. Based on the obtained results, it may be possible to produce a polyphenolic extract from apple wood at an industrial scale without extensive costs or altering the antioxidant properties. This study reveals the potential of apple tree wood residues valorisation through the recovery of phenolic compounds for food, pharmaceutical, and cosmetic applications. [ABSTRACT FROM AUTHOR]

The effect of a dietary incorporation of the seaweeds Ulva lactuca and Chondrus crispus as functional ingredients was evaluated in gilthead seabream (Sparus aurata) juvenile growth, feed efficiency, muscle lipid composition, intermediary metabolism, oxidative status and gut histomorphology. Fish (15 g initial body weight) were fed with isoproteic (46%) and isolipidic (18%) diets with fish meal (FM) and plant feedstuffs (PF) (27:73 protein from FM:PF) as main protein sources (control diet). Three other diets were formulated similar to the control but including 5% U. lactuca, 5% C. crispus or 2.5% of both algae (diets Ulva, Chondrus and Mix, respectively). Dietary incorporation of Ulva did not affect growth performance (P > 0.05) while it leads to higher muscle ΣSFA (saturated fatty acids); and liver lipid peroxidation (LPO). Moreover, lower muscle ΣPUFA (polyunsaturated fatty acids) and plasma glucose was observed. Dietary incorporation of Chondrus leads to lower growth; whole-body dry matter and lipid content; muscle ΣPUFA and ω3 fatty acids; and plasma glucose. In addition, higher muscle ΣMUFA (monounsaturated fatty acids); and liver LPO was observed. Dietary incorporation of both algae (Mix) led to lower growth; whole-body lipid content; muscle ΣPUFA and ω3 fatty acids; plasma glucose; and hepatic PK (pyruvate kinase) and HOAD (3-hydroxyacyl-CoA dehydrogenase). Furthermore, it leads to higher muscle ΣSFA and ΣMUFA; and liver LPO. Overall, no beneficial effects of including the tested seaweeds in the diets was observed, while oxidative status was negatively affected in all dietary treatments. [ABSTRACT FROM AUTHOR]

Honey was the main sweetening agent in the ancient world; it is mentioned in literary sources and archaeologically documented all over the Mediterranean basin. Its production extended throughout different parts of the Roman Empire, with important economic impacts on family economies, both as a foodstuff and as a commercial product. This paper focuses on the chromatographic analysis of Roman Iberian honeypots and ceramic beehives, identifying tracer characteristics from ancient honey in sherds from seven honeypots and three beehives. The obtained results present an important contribution to the knowledge of the local Roman Iberian economy, particularly relating to the production, transport and trade of honey in locally manufactured ceramic containers. [ABSTRACT FROM AUTHOR]

3-Phenoxybenzoic acid (3-PBA) is a shared metabolite of several synthetic pyrethroid pesticides (SPs) resulting from environmental degradation of parent compounds and thus occurs frequently as a residue in samples. Hence, the importance of 3-PBA evaluation after pyrethroid application. There is a gap of analytical methods to determine 3-PBA in soil samples. Therefore, an analytical method that combines the solid-phase extraction (SPE) and gas chromatography-mass spectrometry (GC/MS) detection has been developed for the determination of 3-PBA in soil samples. The analytical method was validated in terms of linearity, sensitivity, intra- and inter-day batch precisions, recoveries, and quantification limits. An SPE method using a Strata X cartridge allows obtaining limits of detection and quantification equal to 4.0 and 13.3 ng g−1, respectively. Under optimized conditions, the method average recovery levels ranged from 70.3 to 93.5% with a relative standard deviation below 3.4%. Method intra- and inter-day precision was under 5.0 and 4.8%, respectively. The developed method was applied to 11 agricultural soil samples in the north of Portugal. The developed methodology allowed for the determination of the pyrethroid metabolite, 3-PBA, in agricultural soil samples at levels of few ng g−1.ᅟ [ABSTRACT FROM AUTHOR]

Phthalates are a group of chemical compounds used as plasticizers in the manufacture of plastic materials. They can be present in many commonly used products. There seems to be a relationship between exposure to phthalates and the occurrence of metabolic dysfunctions, such as a decrease in glucose tolerance, oxidative stress, loss of beta cells, and a decrease in insulin synthesis. As beta cells play a key role in the onset of type 1 diabetes mellitus (T1DM), we sought to investigate the relationship between exposure to phthalates and the diagnosis of T1DM in prepubertal children. Design concentrations of phthalate metabolites were compared in the urine of a population of prepubertal children with new-onset diabetes, patients with T1DM diagnosed more than 6 months previously, and healthy control children. Although the concentrations of DBP and DiBP metabolites were statistically identical in the new-onset diabetes, diabetes, and control groups, there was a clear trend for higher levels of DiBP metabolites in the children with new-onset diabetes. In our sample, there was a trend for higher levels of DiBP metabolites in children with new-onset diabetes. [ABSTRACT FROM AUTHOR]

BPP-BrachyNH is a proline-rich oligopeptide (PRO) firstly identified in skin secretion of the frog Brachycephalus ephippium, which possess in vitro inhibitory activity of angiotensin-I converting enzyme (ACE) and endothelium-dependent vasorelaxant activity. Considering its potential application in the treatment of cardiovascular diseases, the present work assessed the toxicological profile of the BPP-BrachyNH. The in silico toxicity prediction was performed from the best model obtained through the optimization of the FASTA query peptide. This prediction study revealed that BPP-BrachyNH induced high predicted LD values for both humans and rats, and then is well-tolerated in the recommended range. The MTT assay was applied for the in vitro cytotoxic evaluation in murine macrophages. In this assay, a decrease of cell viability was not observed. The in vivo acute toxicological study was performed after the intraperitoneal administration of BPP-BrachyNH at doses of 5 and 50 mg/kg. After intraperitoneal administration, no death, alterations in behavioral parameters or weight gain curve was observed, as well as none in the serum biochemical parameters, and gross pathological and histopathological analyses. These observations demonstrates an acceptable safety profile for BPP-BrachyNH, leading towards further studies focused on investigation of pharmacological and therapeutical applications for this peptide. [ABSTRACT FROM AUTHOR]

Purpose: Application of zero valent iron nanoparticles is an innovative technology for ground water treatment and soil remediation. There are several methods to synthesise nano scale zero valent iron (nZVI), namely through bottom-up methods which consists on chemical reactions using strong reducing agents. In this work, the environmental impacts and costs were determined for two methods, namely the traditional one that uses sodium borohydride and the green method that uses extracts obtained from natural products. Methods: The consideration of environment and economic aspects in the earlier stages of the synthesis processes and in the development of new materials is of great importance since it can help to decide if alternative methods are promising and should be further developed aiming more sustainable processes. In this work, life cycle assessment (LCA) was used as an ecodesign strategy evaluating environmental performance of the two synthesis methods, identifying critical stages of the synthesis processes of nZVI. An economic evaluation and a sensitivity analysis considering a different scenario for electricity production were also performed. Results and discussion: The results obtained in this study showed that the green synthesis method presents lower environmental impacts than the traditional one, roughly 50% lower in the first scenario. In the second scenario, environmental impact of green synthesis corresponds to 38% of the environmental impact of traditional synthesis. In the green method, the critical stage is the extraction process which is closely related to the electricity production. In the traditional method, the reactant use is the critical stage that is related to the production of sodium borohydride. The economic evaluation indicated that the traditional synthesis method is much more expensive than the green synthesis (roughly eight times higher). Conclusions: From the results obtained, it is possible to conclude that the green synthesis method presents lower environmental impacts in both scenarios and lower costs than the traditional synthesis. [ABSTRACT FROM AUTHOR]

A polyoxometalate-nanocarbon composite, PMoV@N-CNT, was prepared by a simple procedure which consisted of the immobilization of phosphovanadomolybdate (PMoV) onto N-doped carbon nanotubes (N-CNT). The FTIR and XPS characterizations confirmed its successful synthesis. The cyclic voltammograms of glassy carbon electrode (GCE) modified with PMoV and PMoV@N-CNT showed four Mo-centred redox processes (Mo) and a vanadium redox process (V). All were surface-confined redox processes. Additionally, PMoV@N-CNT/GCE showed good stability and well-resolved redox peaks with high current intensities. The electrocatalytic sensing properties of PMoV@N-CNT/GCE towards acetaminophen (AC) in the presence of tryptophan (TRP) were evaluated by square wave voltammetry. Under the conditions used, the peak current increased linearly with AC concentration in the presence of TRP, with a linear range from 1.5 × 10 to 3.9 × 10 mol dm and a detection limit of 1.0 × 10 mol dm. [ABSTRACT FROM AUTHOR]

Pesticides are among the most investigated priority pollutants in agricultural products due to their widespread use and toxicity. The olive fruit fly ( Bactrocera oleae) is one of the main pests of the olive tree in Portugal, and for an effective protection against this plague, farmers rely mostly on the use of insecticides. Six olive samples were collected in four olive groves to evaluate the presence of residues of dimethoate used for the combat of olive fruit fly, in table olives at the time of harvest and after brine. QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction was optimized, one factor at a time, applied to the olive samples, and the extracts were analysed using liquid chromatography-diode array detection. Positive results were obtained in two samples at the time of harvest (3.58 and 4.34 mg/kg fw). One olive grove was selected to test two concentrations of salt and assess their influence on the quantity of residues. After brine, dimethoate residues were not detected. [ABSTRACT FROM AUTHOR]

A voltammetric biosensor for Ara h 6 (a peanut allergen) detection in food samples was developed. Gold nanoparticle-modified screen-printed carbon electrodes were used to develop a sandwich-type immunoassay using two-monoclonal antibodies. The antibody-antigen interaction was detected through the electrochemical detection of enzymatically deposited silver. The immunosensor presented a linear range between 1 and 100 ng/ml, as well as high precision (inter-day RSD ≤9.8 %) and accuracy (recoveries ≥96.7 %). The detection and quantification limits were 0.27 and 0.88 ng/ml, respectively. It was possible to detect small levels of Ara h 6 in complex food matrices. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

As children represent one of the most vulnerable groups in society, more information concerning their exposure to health hazardous air pollutants in school environments is necessary. Polycyclic aromatic hydrocarbons (PAHs) have been identified as priority air pollutants due to their mutagenic and carcinogenic properties that strongly affect human health. Thus, this work aims to characterize levels of 18 selected PAHs in preschool environment, and to estimate exposure and assess the respective risks for 3-5-year-old children (in comparison with adults). Gaseous PAHs (mean of 44.5 ± 12.3 ng m) accounted for 87 % of the total concentration (Σ) with 3-ringed compounds being the most abundant (66 % of gaseous Σ). PAHs with 5 rings were the most abundant ones in the particulate phase (PM; mean of 6.89 ± 2.85 ng m) being predominantly found in PM (78 % particulate Σ). Overall child exposures to PAHs were not significantly different between older children (4-5 years old) and younger ones (3 years old). Total carcinogenic risks due to particulate-bound PAHs indoors were higher than outdoor ones. The estimated cancer risks of both preschool children and the staff were lower than the United States Environmental Protection Agency (USEPA) threshold of 10 but slightly higher than WHO-based guideline. [ABSTRACT FROM AUTHOR]

Sorption is commonly agreed to be the major process underlying the transport and fate of polycyclic aromatic hydrocarbons (PAHs) in soils. However, there is still a scarcity of studies focusing on spatial variability at the field scale in particular. In order to investigate the variation in the field of phenanthrene sorption, bulk topsoil samples were taken in a 15 × 15-m grid from the plough layer in two sandy loam fields with different texture and organic carbon (OC) contents (140 samples in total). Batch experiments were performed using the adsorption method. Values for the partition coefficient K (L kg) and the organic carbon partition coefficient K (L kg) agreed with the most frequently used models for PAH partitioning, as OC revealed a higher affinity for sorption. More complex models using different OC compartments, such as non-complexed organic carbon (NCOC) and complexed organic carbon (COC) separately, performed better than single K models, particularly for a subset including samples with Dexter n < 10 and OC <0.04 kg kg. The selected threshold revealed that K -based models proved to be applicable for more organic fields, while two-component models proved to be more accurate for the prediction of K and retardation factor ( R) for less organic soils. Moreover, OC did not fully reflect the changes in phenanthrene retardation in the field with lower OC content (Faardrup). Bulk density and available water content influenced the phenanthrene transport mechanism phenomenon. [ABSTRACT FROM AUTHOR]

Considering tobacco smoke as one of the most health-relevant indoor sources, the aim of this work was to further understand its negative impacts on human health. The specific objectives of this work were to evaluate the levels of particulate-bound PAHs in smoking and non-smoking homes and to assess the risks associated with inhalation exposure to these compounds. The developed work concerned the application of the toxicity equivalency factors approach (including the estimation of the lifetime lung cancer risks, WHO) and the methodology established by USEPA (considering three different age categories) to 18 PAHs detected in inhalable (PM) and fine (PM) particles at two homes. The total concentrations of 18 PAHs (Σ) was 17.1 and 16.6 ng m in PM and PM at smoking home and 7.60 and 7.16 ng m in PM and PM at non-smoking one. Compounds with five and six rings composed the majority of the particulate PAHs content (i.e., 73 and 78 % of Σ at the smoking and non-smoking home, respectively). Target carcinogenic risks exceeded USEPA health-based guideline at smoking home for 2 different age categories. Estimated values of lifetime lung cancer risks largely exceeded (68-200 times) the health-based guideline levels at both homes thus demonstrating that long-term exposure to PAHs at the respective levels would eventually cause risk of developing cancer. The high determined values of cancer risks in the absence of smoking were probably caused by contribution of PAHs from outdoor sources. [ABSTRACT FROM AUTHOR]

Soil vapor extraction (SVE) and bioremediation (BR) are two of the most common soil remediation technologies. Their application is widespread; however, both present limitations, namely related to the efficiencies of SVE on organic soils and to the remediation times of some BR processes. This work aimed to study the combination of these two technologies in order to verify the achievement of the legal clean-up goals in soil remediation projects involving seven different simulated soils separately contaminated with toluene and xylene. The remediations consisted of the application of SVE followed by biostimulation. The results show that the combination of these two technologies is effective and manages to achieve the clean-up goals imposed by the Spanish Legislation. Under the experimental conditions used in this work, SVE is sufficient for the remediation of soils, contaminated separately with toluene and xylene, with organic matter contents (OMC) below 4 %. In soils with higher OMC, the use of BR, as a complementary technology, and when the concentration of contaminant in the gas phase of the soil reaches values near 1 mg/L, allows the achievement of the clean-up goals. The OMC was a key parameter because it hindered SVE due to adsorption phenomena but enhanced the BR process because it acted as a microorganism and nutrient source. [ABSTRACT FROM AUTHOR]

An analytical method using microwave-assisted extraction (MAE) and liquid chromatography (LC) with fluorescence detection (FD) for the determination of ochratoxin A (OTA) in bread samples is described. A 2 orthogonal composite design coupled with response surface methodology was used to study the influence of MAE parameters (extraction time, temperature, solvent volume, and stirring speed) in order to maximize OTA recovery. The optimized MAE conditions were the following: 25 mL of acetonitrile, 10 min of extraction, at 80 °C, and maximum stirring speed. Validation of the overall methodology was performed by spiking assays at five levels (0.1-3.00 ng/g). The quantification limit was 0.005 ng/g. The established method was then applied to 64 bread samples (wheat, maize, and wheat/maize bread) collected in Oporto region (Northern Portugal). OTA was detected in 84 % of the samples with a maximum value of 2.87 ng/g below the European maximum limit established for OTA in cereal products of 3 ng/g. [ABSTRACT FROM AUTHOR]

Ibuprofen is amongst the most worldwide consumed pharmaceuticals. The present work presents the first data in the occurrence of ibuprofen in Portuguese surface waters, focusing in the north area of the country, which is one of the most densely populated areas of Portugal. Analysis of ibuprofen is based on pre-concentration of the analyte with solid phase extraction and subsequent determination with liquid chromatography coupled to fluorescence detection. A total of 42 water samples, including surface waters, landfill leachates, Wastewater Treatment Plant (WWTP), and hospital effluents, were analyzed in order to evaluate the occurrence of ibuprofen in the north of Portugal. In general, the highest concentrations were found in the river mouths and in the estuarine zone. The maximum concentrations found were 48,720 ng L in the landfill leachate, 3,868 ng L in hospital effluent, 616 ng L in WWTP effluent, and 723 ng L in surface waters (Lima river). Environmental risk assessment was evaluated and at the measured concentrations only landfill leachates reveal potential ecotoxicological risk for aquatic organisms. Owing to a high consumption rate of ibuprofen among Portuguese population, as prescribed and non-prescribed medicine, the importance of hospitals, WWTPs, and landfills as sources of entrance of pharmaceuticals in the environment was pointed out. Landfill leachates showed the highest contribution for ibuprofen mass loading into surface waters. On the basis of our findings, more studies are needed as an attempt to assess more vulnerable areas. [ABSTRACT FROM AUTHOR]

An optimised version of the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for simultaneous determination of 14 organochlorine pesticides in carrots was developed using gas chromatography coupled with electron-capture detector (GC-ECD) and confirmation by gas chromatography tandem mass spectrometry (GC-MS/MS). A citrate-buffered version of QuEChERS was applied for the extraction of the organochlorine pesticides, and for the extract clean-up, primary secondary amine, octadecyl-bonded silica (C18), magnesium sulphate (MgSO) and graphitized carbon black were used as sorbents. The GC-ECD determination of the target compounds was achieved in less than 20 min. The limits of detection were below the EU maximum residue limits (MRLs) for carrots, 10-50 μg kg, while the limit of quantification did exceed 10 μg kg for hexachlorobenzene (HCB). The introduction of a sonication step was shown to improve the recoveries. The overall average recoveries in carrots, at the four tested levels (60, 80, 100 and 140 μg kg), ranged from 66 to 111 % with relative standard deviations in the range of 2-15 % ( n = 3) for all analytes, with the exception of HCB. The method has been applied to the analysis of 21 carrot samples from different Portuguese regions, and β-HCH was the pesticide most frequently found, with concentrations oscillating between less than the limit of quantification to 14.6 μg kg. Only one sample had a pesticide residue (β-HCH) above the MRL, 14.6 μg kg. This methodology combines the advantages of both QuEChERS and GC-ECD, producing a very rapid, sensitive and reliable procedure which can be applied in routine analytical laboratories. [ABSTRACT FROM AUTHOR]

This study focused on the occurrence of several EDCs including bisphenol A, estrone (E1), the 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) in fourteen rivers of Portugal. Samples analysis revealed a widespread contamination of BPA especially in Ave, Cávado, Douro, Ferro, Sousa and Vizela Rivers. Achieving 98.4 ng/L for the highest concentration. The estrogens achieved above the method quantification limit (MQL) were E1 in Águeda River and E2 in Ave, Lima and Tâmega Rivers. The maximum concentration detected for E1 was 26.9 ng/L. EE2 was detected only below MQL. [ABSTRACT FROM AUTHOR]

Disposable screen-printed electrodes (SPCE) were modified using a cosmetic product to partially block the electrode surface in order to obtain a microelectrode array. The microarrays formed were electropolymerized with aniline. Scanning electron microscopy was used to evaluate the modified and polymerized electrode surface. Electrochemical characteristics of the constructed sensor for cadmium analysis were evaluated by cyclic and square-wave voltammetry. Optimized stripping procedure in which the preconcentration of cadmium was achieved by depositing at −1.20 V (vs. Ag/AgCl) resulted in a well defined anodic peak at approximately −0.7 V at pH 4.6. The achieved limit of detection was 4 × 10 mol dm. Spray modified and polymerized microarray electrodes were successfully applied to quantify cadmium in fish sample digests. [ABSTRACT FROM AUTHOR]

Total petroleum hydrocarbons (TPH) are important environmental contaminants which are toxic to human and environmental receptors. Several analytical methods have been used to quantify TPH levels in contaminated soils, specifically through infrared spectrometry (IR) and gas chromatography (GC). Despite being two of the most used techniques, some issues remain that have been inadequately studied: a) applicability of both techniques to soils contaminated with two distinct types of fuel (petrol and diesel), b) influence of the soil natural organic matter content on the results achieved by various analytical methods, and c) evaluation of the performance of both techniques in analyses of soils with different levels of contamination (presumably non-contaminated and potentially contaminated). The main objectives of this work were to answer these questions and to provide more complete information about the potentials and limitations of GC and IR techniques. The results led us to the following conclusions: a) IR analysis of soils contaminated with petrol is not suitable due to volatilisation losses, b) there is a significant influence of organic matter in IR analysis, and c) both techniques demonstrated the capacity to accurately quantify TPH in soils, irrespective of their contamination levels. [ABSTRACT FROM AUTHOR]

Pesticides are among the most widely used chemicals in the world. Because of the widespread use of agricultural chemicals in food production, people are exposed to low levels of pesticide residues through their diets. Scientists do not yet have a total understanding of the health effects of these pesticide residues. This work aims to determine differences in terms of pesticide residue content in Portuguese strawberries grown using different agriculture practices. The Quick, Easy, Cheap, Effective, Rugged, and Safe sample preparation method was conducted and shown to have good performance for multiclass pesticides extraction in strawberries. The screening of 25 pesticides residue was performed by gas chromatography-tandem mass spectrometry. In quantitative validation, acceptable performances were achieved with recoveries of 70-120 and <12 % residual standard deviation for 25 pesticides. Good linearity was obtained for all the target compounds, with highly satisfactory repeatability. The limits of detection were in the range of 0.1-28 μg/kg. The method was applied to analyze strawberry samples from organic and integrated pest management (IPM) practices harvested in 2009-2010. The results showed the presence of fludioxonil, bifenthrin, mepanipyrim, tolylfluanid, cyprodinil, tetraconazole, and malathion when using IPM below the maximum residue levels. [ABSTRACT FROM AUTHOR]

Purpose: The sorption of sulfamethoxazole, a frequently detected pharmaceutical compound in the environment, onto walnut shells was evaluated. Methods: The sorption proprieties of the raw sorbent were chemically modified and two additional samples were obtained, respectively HCl and NaOH treated. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric (TG/DTG) techniques were applied to investigate the effect of the chemical treatments on the shell surface morphology and chemistry. Sorption experiments to investigate the pH effect on the process were carried out between pH 2 and 8. Results: The chemical treatment did not substantially alter the structure of the sorbent (physical and textural characteristics) but modified the surface chemistry of the sorbent (acid-base properties, point of zero charge-pH). The solution pH influences both the sorbent's surface charge and sulfamethoxazole speciation. The best removal efficiencies were obtained for lower pH values where the neutral and cationic sulfamethoxazole forms are present in the solution. Langmuir and Freundlich isotherms were applied to the experimental adsorption data for sulfamethoxazole sorption at pH 2, 4, and 7 onto raw walnut shell. No statistical difference was found between the two models except for the pH 2 experimental data to which the Freundlich model fitted better. Conclusion: Sorption of sulfamethoxazole was found to be highly pH dependent in the entire pH range studied and for both raw and treated sorbent. [ABSTRACT FROM AUTHOR]

This paper reports a novel application of microwave-assisted extraction (MAE) of polyphenols from brewer's spent grains (BSG). A 2 orthogonal composite design was used to obtain the optimal conditions of MAE. The influence of the MAE operational parameters (extraction time, temperature, solvent volume and stirring speed) on the extraction yield of ferulic acid was investigated through response surface methodology. The results showed that the optimal conditions were 15 min extraction time, 100 °C extraction temperature, 20 mL of solvent, and maximum stirring speed. Under these conditions, the yield of ferulic acid was 1.31 ± 0.04% ( w/ w), which was fivefold higher than that obtained with conventional solid-liquid extraction techniques. The developed new extraction method considerably reduces extraction time, energy and solvent consumption, while generating fewer wastes. HPLC-DAD-MS analysis indicated that other hydroxycinnamic acids and several ferulic acid dehydrodimers, as well as one dehydrotrimer were also present, confirming that BSG is a valuable source of antioxidant compounds. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

We have developed a new method for single-drop microextraction (SDME) for the preconcentration of organochlorine pesticides (OCP) from complex matrices. It is based on the use of a silicone ring at the tip of the syringe. A 5 μL drop of n-hexane is applied to an aqueous extract containing the OCP and found to be adequate to preconcentrate the OCPs prior to analysis by GC in combination with tandem mass spectrometry. Fourteen OCP were determined using this technique in combination with programmable temperature vaporization. It is shown to have many advantages over traditional split/splitless injection. The effects of kind of organic solvent, exposure time, agitation and organic drop volume were optimized. Relative recoveries range from 59 to 117 %, with repeatabilities of <15 % (coefficient of variation) were achieved. The limits of detection range from 0.002 to 0.150 μg kg. The method was applied to the preconcentration of OCPs in fresh strawberry, strawberry jam, and soil. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Soil vapor extraction (SVE) is an efficient, well-known and widely applied soil remediation technology. However, under certain conditions it cannot achieve the defined cleanup goals, requiring further treatment, for example, through bioremediation (BR). The sequential application of these technologies is presented as a valid option but is not yet entirely studied. This work presents the study of the remediation of ethylbenzene (EB)-contaminated soils, with different soil water and natural organic matter (NOMC) contents, using sequential SVE and BR. The obtained results allow the conclusion that: (1) SVE was sufficient to reach the cleanup goals in 63% of the experiments (all the soils with NOMC below 4%), (2) higher NOMCs led to longer SVE remediation times, (3) BR showed to be a possible and cost-effective option when EB concentrations were lower than 335 mg kg, and (4) concentrations of EB above 438 mg kg showed to be inhibitory for microbial activity. [ABSTRACT FROM AUTHOR]

The performance of an amperometric biosensor constructed by associating tyrosinase (Tyr) enzyme with the advantages of a 3D gold nanoelectrode ensemble (GNEE) is evaluated in a flow-injection analysis (FIA) system for the analysis of l-dopa. GNEEs were fabricated by electroless deposition of the metal within the pores of polycarbonate track-etched membranes. A simple solvent etching procedure based on the solubility of polycarbonate membranes is adopted for the fabrication of the 3D GNEE. Afterward, enzyme was immobilized onto preformed self-assembled monolayers of cysteamine on the 3D GNEEs (GNEE-Tyr) via cross-linking with glutaraldehyde. The experimental conditions of the FIA system, such as the detection potential (−0.200 V vs. Ag/AgCl) and flow rates (1.0 mL min) were optimized. Analytical responses for l-dopa were obtained in a wide concentration range between 1 × 10 mol L and 1 × 10 mol L. The limit of quantification was found to be 1 × 10 mol L with a resultant % RSD of 7.23% ( n = 5). The limit of detection was found to be 1 × 10 mol L (S/N = 3). The common interfering compounds, namely glucose (10 mmol L), ascorbic acid (10 mmol L), and urea (10 mmol L), were studied. The recovery of l-dopa (1 × 10 mol L) from spiked urine samples was found to be 96%. Therefore, the developed method is adequate to be applied in the clinical analysis. [ABSTRACT FROM AUTHOR]

Celiac disease (CD) is an autoimmune enteropathy, characterized by an inappropriate T-cell-mediated immune response to the ingestion of certain dietary cereal proteins in genetically susceptible individuals. This disorder presents environmental, genetic, and immunological components. CD presents a prevalence of up to 1% in populations of European ancestry, yet a high percentage of cases remain underdiagnosed. The diagnosis and treatment should be made early since untreated disease causes growth retardation and atypical symptoms, like infertility or neurological disorders. The diagnostic criteria for CD, which requires endoscopy with small bowel biopsy, have been changing over the last few decades, especially due to the advent of serological tests with higher sensitivity and specificity. The use of serological markers can be very useful to rule out clinical suspicious cases and also to help monitor the patients, after adherence to a gluten-free diet. Since the current treatment consists of a life-long gluten-free diet, which leads to significant clinical and histological improvement, the standardization of an assay to assess in an unequivocal way gluten in gluten-free foodstuff is of major importance. [ABSTRACT FROM AUTHOR]

The electrochemical behaviour of the pesticide metam (MT) at a glassy carbon working electrode (GCE) and at a hanging mercury drop electrode (HMDE) was investigated. Different voltammetric techniques, including cyclic voltammetry (CV) and square wave voltammetry (SWV), were used. An anodic peak (independent of pH) at +1.46 V vs AgCl/Ag was observed in MT aqueous solution using the GCE. SWV calibration curves were plotted under optimized conditions (pH 2.5 and frequency 50 Hz), which showed a linear response for 17–29 mg L−1. Electrochemical reduction was also explored, using the HMDE. A well defined cathodic peak was recorded at −0.72 V vs AgCl/Ag, dependent on pH. After optimizing the operating conditions (pH 10.1, frequency 150 Hz, potential deposition −0.20 V for 10 s), calibration curves was measured in the concentration range 2.5×10−1 to 1.0 mg L−1 using SWV. The electrochemical behaviour of this compound facilitated the development of a flow injection analysis (FIA) system with amperometric detection for the quantification of MT in commercial formulations and spiked water samples. An assessment of the optimal FIA conditions indicated that the best analytical results were obtained at a potential of +1.30 V, an injection volume of 207 μL and an overall flow rate of 2.4 ml min−1. Real samples were analysed via calibration curves over the concentration range 1.3×10−2 to 1.3 mg L−1. Recoveries from the real samples (spiked waters and commercial formulations) were between 97.4 and 105.5%. The precision of the proposed method was evaluated by assessing the relative standard deviation (RSD %) of ten consecutive determinations of one sample (1.0 mg L−1), and the value obtained was 1.5%. [ABSTRACT FROM AUTHOR]

Fluvoxamine (FVX) can be reduced at a mercury-drop electrode, with a maximum peak current intensity being obtained at a potential of −0.7 V vs. Ag/AgCl, in an aqueous electrolyte solution of pH 2. The compound was determined in a pharmaceutical product and in spiked human serum by square-wave adsorptive-stripping voltammetry (SWAdSV) after accumulation at the electrode surface, under batch conditions. Because the presence of dissolved oxygen did not interfere significantly with the analysis, it was also possible to determine FVX in the pharmaceutical product by use of a flow-injection analysis (FIA) system with SWAdSV detection. The methods developed were validated and successfully applied to the quantification of FVX in a pharmaceutical product. Recoveries between 76 and 89% were obtained in serum analysis. The FIA–SWAdSV method enabled analysis of up to 120 samples per hour at reduced cost, implying the possibility of competing with the chromatographic methods usually used for this analysis. [ABSTRACT FROM AUTHOR]

An extraction-anodic adsorptive stripping voltammetric procedure using microwave-assisted solvent extraction and a gold ultramicroelectrode was developed for determining the pesticide ametryn in soil samples. The method is based on the use of acetonitrile as extraction solvent and on controlled adsorptive accumulation of the herbicide at the potential of 0.50 V (vs. Ag/AgCl) in the presence of Britton-Robinson buffer (pH 3.3). Soil sample extracts were analysed directly after drying and redissolution with the supporting electrolyte but without other pre-treatment. The limit of detection obtained for a 10 s collection time was 0.021 μg g−1. Recovery experiments for the global procedure, at the 0.500 μg g−1 level, gave satisfactory mean and standard deviation results which were comparable to those obtained by HPLC with UV detection. [ABSTRACT FROM AUTHOR]

The work presented describes the development and evaluation of two flow-injection analysis (FIA) systems for the automated determination of carbaryl in spiked natural waters and commercial formulations. Samples are injected directly into the system where they are subjected to alkaline hydrolysis thus forming 1-naphthol. This product is readily oxidised at a glassy carbon electrode. The electrochemical behaviour of 1-naphthol allows the development of an FIA system with an amperometric detector in which 1-naphthol determination, and thus measurement of carbaryl concentration, can be performed. Linear response over the range 1.0×10-7 to 1.0×10-5 mol L-1, with a sampling rate of 80 samples h-1, was recorded. The detection limit was 1.0×10-8 mol L-1. Another FIA manifold was constructed but this used a colorimetric detector. The methodology was based on the coupling of 1-naphthol with phenylhydrazine hydrochloride to produce a red complex which has maximum absorbance at 495 nm. The response was linear from 1.0×10-5 to 1.5×10-3 mol L-1 with a detection limit of 1.0×10-6 mol L-1. Sample-throughput was about 60 samples h-1. Validation of the results provided by the two FIA methodologies was performed by comparing them with results from a standard HPLC–UV technique. The relative deviation was <5%. Recovery trials were also carried out and the values obtained ranged from 97.0 to 102.0% for both methods. The repeatability (RSD, %) of 12 consecutive injections of one sample was 0.8% and 1.6% for the amperometric and colorimetric systems, respectively. [ABSTRACT FROM AUTHOR]

On the basis of its electrochemical behaviour a new flow-injection analysis (FIA) method with amperometric detection has been developed for quantification of the herbicide bentazone (BTZ) in estuarine waters. Standard solutions and samples (200 µL) were injected into a water carrier stream and both pH and ionic strength were automatically adjusted inside the manifold. Optimization of critical FIA conditions indicated that the best analytical results were obtained at an oxidation potential of 1.10 V, pH 4.5, and an overall flow-rate of 2.4 mL min–1. Analysis of real samples was performed by means of calibration curves over the concentration range 2.5×10–6 to 5.0×10–5 mol L–1, and results were compared with those obtained by use of an independent method (HPLC). The accuracy of the amperometric determinations was ascertained; errors relative to the comparison method were below 4% and sampling rates were approximately 100 samples h–1. The repeatability of the proposed method was calculated by assessing the relative standard deviation (%) of ten consecutive determinations of one sample; the value obtained was 2.1%. [ABSTRACT FROM AUTHOR]

A method for the determination of some pesticide residues in must and wine samples was developed using solid-phase microextraction (SPME) and gas chromatography – electron capture detection (GC/ECD). The procedure only needs dilution as sample pre-treatment and is therefore simple, fast and solvent-free. Eight fungicides (vinclozolin, procymidone, iprodione, penconazole, fenarimol, folpet, nuarimol and hexaconazole), one insecticide (chlorpyriphos) and two acaricides (bromopropylate and tetradifon) can be quantified. Good linearity was observed for all the compounds in the range 5–100 μg/L. The reproducibility of the measurements was found acceptable (with RSD’s below 20%). Detection limits of 11 μg/L, on average, are sufficiently below the proposed maximum residue limits (MRL’s) for these compounds in wine. The analytical method was applied to the determination of these compounds in Portuguese must and wine samples from the Demarcated Region of Alentejo, where any residues could be detected. [ABSTRACT FROM AUTHOR]

Biomarkers are recognised sensitive early-warning tools of biological effects in aquatic organisms. In this scope, the main aim of this study was to investigate the potential usefulness of a battery of biomarkers, evaluated in different benthic macroinvertebrate taxa, to discriminate aquatic ecosystems with different levels of ecological status and to provide further clues supporting environmental management. The study took place during the autumn of 2013 and the spring and summer of 2014, and the study cases were two Mediterranean rivers (Âncora and Ferreira rivers), differing in their ecological status. The biomarkers determined are widely employed and comprise a large set of biochemical responses: the activity of enzymes (cholinesterases, glutathione S-transferases, catalase and lactate dehydrogenase) and the levels of lipid peroxidation. They were assessed seasonally and in different macroinvertebrate taxa. Thirteen water physico-chemical parameters were also seasonally determined, and the concentration of seven organophosphorus pesticides and the percentage of 32 trace metals in sediments were determined in the spring. This is particularly useful for water management. Based on this, authorities can take actions to prevent further damage in the ecological status. Multivariate analyses showed distinct patterns of biological response for the Calopteryx spp., Chironomidae and Baetis spp. taxa. Calopteryx spp. and Chironomidae, in particular, showed distinct response patterns for the two rivers, which were fairly stable across seasons. This study sets the foundations for future cost-effective biomonitoring campaigns in Mediterranean rivers, allowing to establish historical data important to understand ecosystem evolution, as well as baseline levels of diagnostic biomarkers in informative macroinvertebrate taxa. [ABSTRACT FROM AUTHOR]