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Purpose: To improve the understanding of the fate and behaviour of per- and polyfluoroalkyl substances (PFAS) in estuarine environments, this study investigated the effect of organic carbon (OC) and salinity on the desorption of perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonic acid (PFHxS) from five freshly contaminated estuarine sediments. Materials and methods: Batch desorption experiments were completed following sorption experiments in uncontaminated sediments that covered a range of OC contents (1.1–10%), as well as in field-contaminated sediments. PFAS-free seawater of different salinities was used for the desorption. Results and discussion: The range of PFAS desorbed from the sediments were consistent with the sorption behaviour of these compounds with the desorption of PFOS notably lower than PFOA and PFHxS. Approximately 9–69% PFOS, 33–91% PFOA and 43–116% PFHxS were desorbed after the 1st 24-h desorption indicating the PFOS' stronger interaction/sorption with the sediments. The lowest percentages of PFAS were desorbed from sediments with high OC content exposed to highly saline conditions. The influence of salinity on desorption was, however, less than OC content which appeared to have a "protective" effect, inhibiting desorption of PFAS from these sediments. These results agree with experiments on field-contaminated sediments. Conclusion: Over-all, results point to the importance of both OC and salinity in reducing release of PFAS from contaminated estuarine sediments, with OC being key to controlling PFAS mobility. [ABSTRACT FROM AUTHOR]

Environmental context: There are great concerns around current wide usage of copper-based agrochemicals. We compare the fate of nano- and conventional forms of copper, in particular their resistance to wash-off by rain (rainfastness), following their application to citrus leaves. Results showing large differences between the formulations in the amount and forms of copper washed from the leaves provide essential information to optimise agrochemical efficacy while minimising the environmental impact. This study compares the rainfastness of nine forms of Cu, including nano and conventional Cu-based fungicide formulations, as well as their salt or bulk equivalents. Rainfastness is the ability to resist wash-off; it is a key property for improving pesticide formulations and for assessing the potential transfer of pesticides to the soil. A new protocol was developed to characterise losses of Cu from treated leaves. It consisted of dipping the leaves in rainwater and then in an acid/ethanol mixture followed by size fractionation. The proportion of Cu lost by wash-off from citrus leaves ranged from <2 % (Tribasic, nCuO or Cu(OH)2) up to 93 % (CuSO4) of the initial amount of Cu applied. Intermediate Cu losses were observed for formulations with silica (nano)particles (9–14 % of applied Cu), Kocide (22 %), ChampDP (31 %), and a formulation with graphene oxide (47 %). Smaller particles generally resulted in less wash-off, possibly due to stronger attachment to the leaf surface, but other factors such as the particle shape and solubility also played an essential role. The retention of nCuO to the leaves was particularly high, and the exact mechanisms involved (e.g. foliar uptake) deserve further work. Most of the Cu was washed off in its ionic form (>74 %). Two Cu formulations (one commercial formulation and the formulation with graphene oxide) also showed wash off in significant proportions of Cu (~17 %) in the nano-sized fraction. This study provides essential information on the amounts and forms of Cu that may reach the soil after the application of Cu-based agrochemicals. The great diversity in behaviour across the range of formulations considered highlights the need for more systematic research to fully exploit the potential improvements of current agrochemicals through (nano)formulation technologies. Environmental context. There are great concerns around current wide usage of copper-based agrochemicals. We compare the fate of nano- and conventional forms of copper, in particular their resistance to wash-off by rain (rainfastness), following their application to citrus leaves. Results showing large differences between the formulations in the amount and forms of copper washed from the leaves provide essential information to optimise agrochemical efficacy while minimising the environmental impact. [ABSTRACT FROM AUTHOR]

A survey was conducted in eight secondary schools located in two watersheds in Gujarat and Rajasthan (semi-arid region of India) to assess students’ perceptions about groundwater scarcity issues and the impact of the scarcity on their educational opportunities. Survey responses to a detailed questionnaire by a cohort of students in both watersheds; school attendance records of year 8 class students (13–14 years old) and responses gathered via a socio-economic survey involving 500 families in the study area were used in the study. In both watersheds, >90% students identified groundwater scarcity as a major issue. Required to work at home or farm, about 65% students in Gujarat and 60% in Rajasthan missed school for up to 2 days/month; and a smaller proportion (∼ 30%) missed schools for 4 or more days/month. School absenteeism was found to be linked with gender; female students missed schools more frequently than their male counterpart. The school attendance records in Rajasthan showed that the frequency of female students missing schools for 5 or more days/month was on an average 2–10 times greater than that for males. The gender difference in absenteeism in all schools was statistically significant (P < .018**). The study highlighted that groundwater scarcity in the study area, and consequent demand on their time for household work including fetching drinking water are contributing factors towards limiting their educational and economic opportunities. Groundwater scarcity can be one of the key factors that can limit inclusiveness and empowerment of women and need to be considered in policy-making. [ABSTRACT FROM PUBLISHER]

The contamination of major continental river systems by endocrine-active chemicals (EACs) derived from the discharge of wastewater treatment plant (WWTP) effluents can affect human and ecosystem health. As part of a long-term effort to develop a native fish model organism for assessment of endocrine disruption in Australia's largest watershed, the Murray-Darling River Basin, the present study evaluated endocrine disruption in adult males of the native Australian Murray rainbowfish (Melanotaenia fluviatilis) exposed to effluent from an activated sludge WWTP and water from the Murray River during a 28-d, continuous-flow, on-site experiment. Analysis of the WWTP effluent and river water detected estrone and 17β-estradiol at concentrations up to approximately 25 ng L−1. Anti-estrogenicity of effluent samples was detected in vitro using yeast-based bioassays (yeast estrogen screen) throughout the experiment, but estrogenicity was limited to the first week of the experiment. Histological evaluation of the testes indicated significant suppression of spermatogenesis by WWTP effluent after 28 d of exposure. Plasma vitellogenin concentrations and expression of vitellogenin messenger RNA in liver were not significantly affected by exposure to WWTP effluent. The combination of low contaminant concentrations in the WWTP effluent, limited endocrine disrupting effects in the Murray rainbowfish, and high in-stream dilution factors (>99%) suggest minimal endocrine disruption impacts on native Australian fish in the Murray River downstream from the WWTP outfall. Environ Toxicol Chem 2015;34:1078-1087. © 2015 SETAC [ABSTRACT FROM AUTHOR]

Active pharmaceutical ingredients (APIs) can enter the natural environment during manufacture, use and/or disposal, and consequently public concern about their potential adverse impacts in the environment is growing. Despite the bulk of the human population living in Asia and Africa (mostly in low- or middle-income countries), limited work relating to research, development and regulations on APIs in the environment have so far been conducted in these regions. Also, the API manufacturing sector is gradually shifting to countries with lower production costs. This paper focuses mainly on APIs for human consumption and highlights key differences between the low-, middle- and high-income countries, covering factors such as population and demographics, manufacture, prescriptions, treatment, disposal and reuse of waste and wastewater. The striking differences in populations (both human and animal), urbanization, sewer connectivity and other factors have revealed that the environmental compartments receiving the bulk of API residues differ markedly between low- and high-income countries. High sewer connectivity in developed countries allows capture and treatment of the waste stream (point-source). However, in many low- or middle-income countries, sewerage connectivity is generally low and in some areas waste is collected predominantly in septic systems. Consequently, the diffuse-source impact, such as on groundwater from leaking septic systems or on land due to disposal of raw sewage or septage, may be of greater concern. A screening level assessment of potential burdens of APIs in urban and rural environments of countries representing low- and middle-income as well as high-income has been made. Implications for ecological risks of APIs used by humans in lower income countries are discussed. [ABSTRACT FROM AUTHOR]

Indaziflam is a relatively new herbicide for which sorption–desorption information is lacking, and nothing is available on its metabolites. Information is needed on the multiple soil and pesticide characteristics known to influence these processes. For four soils, the order of sorption was indaziflam (N-[1R,2S)-2,3-dihydro-2,6-dimethyl-1H-inden-1-yl]-6-[(1R)-1-fluoroethyl]-1,3,5-triazine-2,4-diamine) (sandy clay loam:Kf= 5.9, 1/nf= 0.7,Kfoc= 447; sandy loam:Kf= 3.9, 1/nf= 0.9,Kfoc= 276) > triazine indanone metabolite (N-[(1R,2S)-2,3-dihydro-2,6-dimethyl-3-oxo-1H-inden-1-yl]-6-[(1R)-1-fluoroethyl]-1,3,5-triazine-2,4-diamine) (sandy clay loam:Kf= 2.1, 1/nf= 0.8,Kfoc= 177; sandy loam:Kf= 1.7, 1/nf= 0.9,Kfoc= 118) > fluoroethyldiaminotriazine metabolite (6-[(1R-1-Fluoroethyl]-1,3,5-triazine-2,4-diamine) (sandy clay loam:Kf= 0.3, 1/nf= 0.9,Kfoc= 28; sandy loam:Kf= 0.3, 1/nf= 0.9,Kfoc= 22) = indaziflam carboxylic acid metabolite (2S,3R)-3-[[4-amino-6-[(1R)-1-fluoroethyl]-1,3,5-triazin-2-yl]amino]-2,3-dihydro-2-methyl-1H-indene-5-carboxylic acid) (sandy clay loam:Kf= 0.3, 1/nf= 0.9,Kfoc= 22; sandy loam:Kf= 0.5, 1/nf= 0.8,Kfoc= 32). The metabolites being more polar than the parent compound showed lower sorption. Desorption was hysteretic for indaziflam and triazine indanone metabolite, but not for the other two metabolites. Unsaturated transient flowKd's were lower than batchKd's for indaziflam, but similar for fluoroethyldiaminotriazine metabolite. BatchKd's would overpredict potential offsite transport if desorption hysteresis is not taken into account. [ABSTRACT FROM AUTHOR]

Biodegradation of the ultraviolet (UV) filter benzophenone-3 (BP-3) was investigated in the laboratory to understand its behavior and fate under oxic and anoxic (nitrate, sulfate, and Fe [III]-reducing) conditions. Biodegradation experiments were conducted in microcosms with 10% of activated sludge and digested sludge under oxic and anoxic conditions, respectively. Benzophenone-3 was well degraded by microorganisms under each redox condition. Under the redox conditions studied, the biodegradation half-life for BP-3 had the following order: oxic (10.7 d) > nitrate-reducing (8.7 d) > Fe (III)-reducing (5.1 d) > sulfate-reducing (4.3 d) ≥ anoxic unamended (4.2 d). The results suggest that anaerobic biodegradation is a more favorable attenuation mechanism for BP-3. Biodegradation of BP-3 produced two products, 4-cresol and 2,4-dihydroxybenzophenone, under oxic and anoxic conditions. Biotransformation of BP-3 to 2,4-dihydroxybenzophenone by way of demethylation of the methoxy substituent ( O-demethylation) occurred in cultures under each redox condition. The further biotransformation of 2,4-dihydroxybenzophenone to 4-cresol was inhibited under oxic, nitrate-reducing, and sulfate-reducing conditions. Environ. Toxicol. Chem. 2012;31:289-295. © 2011 SETAC [ABSTRACT FROM AUTHOR]

Pharmaceuticals released into aquatic systems are expected to sorb to sediments to varying degrees. Their sorption is likely to influence their fate and, ultimately, the risk they pose to aquatic organisms. This has led to the European Medicines Agency requiring an assessment of affinity to solids, using batch sorption methods, for the environmental risk assessment (ERA) of new human medicines. However, a large body of data is generated before pharmaceuticals are released onto the market, including their extent of distribution throughout the human body, measured by the volume of distribution (VD). In the present study, batch sorption experiments were undertaken using 12 different soils and sediments to determine whether VD was a good indicator of experimental Kd values for 21 pharmaceuticals. The r² values obtained from the regressions ranged from 0.39 to 0.76 (with a median value of 0.5) and all regressions were found to be significant. The use of this more comprehensive set of soils and sediments was consistent with previous studies comparing VD and Kd, despite the Kd values of the selected pharmaceuticals varying greatly between soils. The relationship between Kd and VD was greatly improved when zwitterionic antibiotics and carbamazepine were not included, possibly due to complex sorption or pharmacokinetic behavior. There are likely to be a number of factors affecting the sorption of pharmaceuticals that cannot be explained by VD. However, further work may elucidate how these factors can be accounted for, enabling VD to be effectively used to facilitate the ERA of human pharmaceuticals with already available information. [ABSTRACT FROM AUTHOR]

The present study assessed contamination and toxicity of sediments from seven remediated and remnant wetland sites within Sydney Olympic Park, Australia, and four unremediated Sites adjacent to its boundary using chemical analysis and a luminescent bacterial biosensor assay (Escherichia coli). Concentrations of metals (Pb, Cr, Cu, Ni, Zn, Cd, and As) and persistent organic chemicals (DDT and its metabolites, dichlorodiphenyldichloroethane and dichlorodiphenyldichloroethylene; polycyclic aromatic hydrocarbons; polychlorinated biphenyls; and polychlorinated dibenzo-p-dioxins and dibenzofurans) in sediments and their pore-water samples were determined. Zinc concentrations were the highest of the metals in the sediments (84-618 mg/kg), and at eight sites, metal concentrations in sediments exceeded the Australian ecological trigger values for Pb, Zn, and Ni. Concentrations of organic contaminants in the sediments exceeded the trigger values at all 11 sites for DDTs, at 6 sites for polycyclic aromatic hydrocarbons, and 5 sites for polychlorinated biphenyls. Sediment samples from the four unremediated sites outside the Sydney Olympic Park had dioxin concentrations greater than 200 pg (toxic equivalency per gram). The same four sites were identified as contaminated in pore-water toxicity tests with the luminescent biosensor, generally consistent with the bioavailable fractions of the contaminants (pore-water and Tenax® extraction data), as well as dioxin levels, in the sediments. Preliminary toxicity identification and evaluation tests of the pore water from the four sites outside the park demonstrated that organic contaminants were the main cause of toxicity to E. coli, with no evidence that metals contributed to the toxicity of the pore water. [ABSTRACT FROM AUTHOR]

Triclosan (TCS) antimicrobial compound is used in personal care products such as shampoos and soaps. The TCS compound can survive the treatment process and is often present in the sewage effluent and biosolids. We investigated the impact of TCS upon selected microbiological and biochemical parameters in two contrasting Australian soils. Substrate-induced respiration and nitrification, plus activities of four enzymes (relevant for carbon and nitrogen turnover), were measured using Organisation for Economic Co-operation and Development protocols after exposing soils to TCS at concentrations of 0, 1, 5, 10, 50, and 100 mg/ kg of soil. Respiration in the sandy soil was not affected by the addition of TCS, but in clay soil it decreased to TCS at 50 mg/ kg of soil. The nitrification process was affected in both soils. In the sandy soil, TCS showed a negative effect on the nitrate and nitrite production at 5 mg/kg. In contrast, in the clay soil, the effect was noticeable only at concentrations greater than 50 mg/kg. The response of four enzymes (acid and alkali phosphatase, β-glucosidase, and chitinase) in the two soils was variable, and only β-glucosidase showed some response to TCS addition. The study demonstrated that TCS at concentrations below 10 mg/kg can disturb the nitrogen cycle in some soils. A first-tier hazard assessment highlighted the need for further work on TCS impact on soil microorganisms. [ABSTRACT FROM AUTHOR]

The fate and removal of the estrogens 17β-estradiol (E2), estrone (E1), and 17α-ethynylestradiol (EE2) and of the xenoestrogens bisphenol A (BPA), 4-tert-octylphenol (4-t-OP), 4-nonylphenol (4-NP), and nonylphenol mono- and diethoxylate (NPEO1 and NPEO2, respectively) were investigated in four South Australian sewage treatment plants (STPs; plants A-D) with different treatment technologies. The concentrations in the effluent from the two-year survey were similar to those reported in other studies. In the effluent, 4-NP, NPEO1, and NPEO2 had total concentrations up to 8 μg/L, which were much higher than those of BPA and 4-t-OP. Estrone had the highest concentrations among the three estrogens, ranging between 13.3 and 39.3 ng/L, whereas the concentrations for E2 and EE2 varied between 1.0 and 4.2 ng/L and between 0.1 and 1.3 ng/L, respectively. The removal rates for the estrogens and xenoestrogens were variable but consistent with the plant performance parameters (biochemical oxygen demand, suspended solids, and ammonia). Considering all the estrogenic compounds analyzed in the present study, plant D, with a series of anaerobic and aerobic lagoons, was the least efficient of the four STPs in the removal of these compounds. The removal rates for 4-NP, NPEO1, and NPEO2 within the plants were 92% for plant A, with conventional activated sludge treatment; 80% for plant B, with two oxidation ditches; 70% for plant C, with three bioreactors; and 64% for plant D, with 10 lagoons in series. Comparatively, the removal of estrogens was lower, with rates ranging between 47 and 68% for E2 at the four plants. Both E1 and EE2 were more persistent during treatment, especially in plants C and [ABSTRACT FROM AUTHOR]

Off-site movement of pesticides from furrow-irrigated agriculture has been a concern in the Ord River Irrigation Area, Western Australia. This paper reports on the effectiveness of incorporation of pesticides by cultivator or power harrows before irrigating, and spraying pesticides only onto beds to minimise off-site transport. Incorporation of pesticides by power harrows prior to irrigation was found to be more effective in decreasing the off-site transport of a more strongly sorbed pesticide, endosulfan. The average load of total endosulfan (α + β+ sulfate) decreased by 74% (P < 0.01) from 11.41 g ha-1 from the conventionally treated bays to 2.96 g ha-1 from the incorporated irrigation bays. The total average load of atrazine leaving the irrigation bays was decreased by 81% (P < 0.05) from 87.82 g ha-1 under the conventional practice of spraying the whole field to 16.95 g ha-1 by spraying the beds only. A reduction of 52% in total average load of metolachlor was observed following incorporation with power harrows, but this was not significant. Incorporation by cultivator or by power harrows decreased the total load of atrazine or metolachlor leaving the irrigation bays over the whole irrigation period, but these treatments were not shown to be statistically significant, which may have been due to the limited number of field replicates. Incorporation of strongly sorbed pesticides (e.g. endosulfan) prior to irrigation significantly decreased the off-site transport of these pesticides in a furrow irrigation system and may be a useful practice to minimise off-site transport of other similar pesticides. Minimising off-site transport of weakly sorbed pesticides (e.g. atrazine and metolachlor) from a furrow irrigation system is more difficult. The nature of furrow irrigation makes it highly conducive to pesticide transport, particularly of weakly sorbed pesticides, and further work is needed to develop strategies to minimise the movement of this group of pesticides to water bodies. [ABSTRACT FROM AUTHOR]

To have an effective barrier against invading termites around building structures and to assess the potential risks to the urban environment and human beings, we need to understand the fate of termiticides applied in urban soil. The movement and degradation of a new termiticide, fipronil, were investigated in Australian soils following standard termiticide treatment methods (surface application under slab and trenching treatments along walls). Surface application studies in three field sites showed slow dissipation and little movement for fipronil in all three soils under the simulated slab during a three-year period. The greatest mass of the chemical residues remained in the quartzite sand layer (thickness, 5 cm), and only small amounts of these were found to have migrated into the soil layers (depth, 0-15 cm) underneath the quartzite sand layer. Of the three metabolites (desulfinyl, sulfide, and sulfone) found in the soils, the sulfone derivative had the highest concentration. Persistence of fipronil was affected by application rate. The time for 50% loss of the total toxic components (fipronil plus its metabolites) in the quartzite sand layer (thickness, 5 cm) ranged from 200 to 326 d for the low rate (0.15 g active ingredient/m2) and from 633 to 674 d for the high application rate (3 g active ingredient/m²). One-year trenching studies at two sites in Adelaide (Roseworthy Farm [RF] and Terretfield [TF]; South Australia, Australia) showed that vertical movement and dissipation of fipronil occurred in the soils. The average concentration of fipronil in the trenches (depth, 0-30 cm) decreased from 33.7 to 14.9 mg/kg in the loam soil at the RF site and from 39.4 to 14.6 mg/kg in the clay soil at the TF site over the year. With time under the natural weather condition, fipronil and its derivatives were found in the deeper soil sections without treatment (depth, 20-30 cm). However, laboratory studies using repacked soil columns showed low mobility in the loam soil from the RF site and a variably charged clay soil from Malanda (Queensland, Australia) under intermittent wetting and drying conditions. [ABSTRACT FROM AUTHOR]

We investigated bioavailability and biodegradation of carbaryl (1-naphthyl methylcarbamate) in a soil with a long history of pesticide contamination from a storage facility located at Mamoon Kanjan, Pakistan. Carbaryl is weakly sorbed and generally considered to be easily degradable in soil. Extraction studies revealed that 49% of the total carbaryl in soil (88.0 mg kg-1) was not water-extractable and also not bioavailable, as demonstrated by inoculation of the contaminated soil with a carbaryl-degrading, mixed bacterial culture. Inoculation of the contaminated soil with the carbaryl-degrading culture showed that the bacteria were capable of degrading only the available (i.e., water-extractable) fraction of the pesticide. When the soil was pulverized in a ball mill to enhance the release of residue, an additional 19% of the carbaryl became bioavailable. A significant proportion of residue (≈33%) remained unavailable. The long (>12 years) contact time between the pesticide and soil (i.e., aging), allowing possible sequestration into soil nanopores and the organic matter matrices, is suggested to have rendered the pesticide unavailable for microbial degradation. High concentration (88.0 mg kg-1) in soil facilitated its persistence and sequestration. Results from the present study demonstrate that even a weakly sorbed and easily degradable pesticide, carbaryl, is effectively sequestrated in soil with time, rendering it partly inaccessible to microorganisms and affecting the bioavailability of the compound. [ABSTRACT FROM AUTHOR]

A high-performance liquid chromatography method with diode-array detection (HPLC-DAD) is described for the determination of three neonicotinoid insecticides imidacloprid, thiacloprid, and thiamethoxam in soil and water. The soil samples were extracted with acetonitrile, while the water samples were extracted using C18 cartridges. The mean recoveries plus standard deviations for spiked soil samples were 82 ± 4.2% for thiamethoxam, 99 ± 4.2% for imidacloprid and 94 ± 1.4% for thiacloprid. The recoveries for water samples ranged from 87 ± 3.4% for thiamethoxam to 97 ± 3.9% for imidacloprid and 97 ± 2.6% for thiacloprid. The limits of quantitation (LOQ) were 0.1, 0.1, 0.01 mg/kg in soil (5 g), and 2, 2, 0.5 µg/L in water (50 mL) for thiamethoxam, imidacloprid, and thiacloprid, respectively. [ABSTRACT FROM AUTHOR]

The potential of five nonionic surfactants, Triton X-100, Brij35, Ethylan GE08, Ethylan CD127, and Ethylan CPG660 for enhancing release of carbaryl and ethion from two long-term contaminated soils was evaluated using the batch method. Incorporation of the surfactants into soils enhanced the release of both pesticides to various extents, which could be related to the type of pesticides and type and the amount of surfactants added. Release of ethion was dramatically enhanced by aqueous concentrations of surfactants above their critical micelle concentration values. This was attributed to solubility enhancement through incorporation of the highly hydrophobic compound within surfactant micelles. A concentration of 10 g L−1 of various surfactants released >70% of the total ethion from the soil irrespective of the surfactant. For carbaryl, the surfactants were effective at low concentrations and dependence on concentration was lower than in the case of ethion. The ethylan surfactants (GE08, CD127, and CPG660) had a higher potential than Triton X-100 and Brij35 for releasing the pesticides. However, there was still a significant portion of carbaryl (11% of the total) and ethion (17% of the total) left in the soil. Our study also showed that there must be an optimal concentration of each surfactant to maximize the mass transfer of pesticides. At some threshold concentration level, additional surfactant started to inhibit the mass transfer of solute from the soil into the water. The results suggested that surfactants could help remediation of soils polluted by pesticides. The choice of surfactant should be made based on the properties of pesticides. [ABSTRACT FROM AUTHOR]

Aquifer storage and recovery (ASR) is an emerging and effective management technique in reclaiming and reusing waste water. During ASR, attenuation processes such as sorption and degradation may play an important role in removing trace organic contaminants in injected waste water. This study mainly investigated the role of treated sewage effluent injectant (the waste water injected into the aquifer) on degradation of two endocrine disrupting compounds, 17β-estradiol (E2) and 17α-ethynylestradiol (EE2), in the laboratory by comparing their behavior in incubation media--aquifer sediment/ground water slurry from the Bolivar experimental ASR site in South Australia and sediment/effluent slurry. Biodegradation of the two compounds in the sediment/ground water media (1:1, w/w) and in the sediment/effluent media (1:1, w/w) were conducted under aerobic and anaerobic conditions at 20 °C. In both incubation media, E2 showed a rapid biodegradation with a DT50 value (time for 50% loss) of ∼2 days under aerobic conditions. E2 degraded slowly in both aquifer media under anaerobic conditions; however, the anaerobic degradation was noted to be somewhat faster in the sediment/effluent media. In contrast, EE2 was found to be resistant to biodegradation and remained almost unchanged within 70 days under anaerobic conditions in both incubation media. The mobility of the two compounds in the aquifer would depend on their sorption. The sorption coefficients measured on the aquifer sediment were 7.7 ± 3.4 L/kg for E2 and 10.6 ± 5.1 L/kg for EE2 using batch equilibration methods. The corresponding retardation factors were calculated to be 25 for E2 and 34 for EE2 based on the physical properties of the aquifer material in the Bolivar ASR site. This study showed that while E2 has modest sorption affinity for aquifer material, it is rapidly biodegraded with or without the supplement of effluent under... [ABSTRACT FROM AUTHOR]

Pesticides, being toxic by design, cause considerable public concern about their possible non‐target impact on the ecosystem and human health. Pesticide use has increased substantially in Australia and globally over the last two decades, partly due to changes in tillage practices. Some 400 chemically active ingredients, of varying properties, are currently available in Australia alone. Pesticide residues have been found, mostly at acceptable levels, in food commodities and in surface and ground water bodies in Australia. Such contamination needs to be minimized. However, the variety of pesticides, their use under a range of soil and climatic conditions and the complexity of processes governing their fate make this task particularly daunting. Furthermore, as little local data is available for Australian conditions, there is danger in extrapolating overseas Temperate Zone data, especially for risk assessment in tropical regions. The effect of farming practices, e.g. conservation tillage, on run‐off and leaching losses, needs better understanding and quantification. Such studies aimed at providing knowledge on the fate and persistence of pesticides must be supported by sound information on pesticide usage (inputs), particularly at catchment‐scale. Correct sampling and analytical protocols are crucial for any research or monitoring study. Analysts are faced with a continuous demand for newer, cost effective and improved analytical methods for pesticides and their metabolites, for better sensitivity and quality control. [ABSTRACT FROM PUBLISHER]

Estrogenic compounds may enter the environment when biosolids are applied to land. In the present study, soil samples were collected over 4 mo from a field trial following addition of biosolids. The recombinant yeast estrogen screen bioassay identified estrogenic activity in the soil at all sampling times to concentrations up to 2.3 µg 17β-estradiol equivalency/kg. The present results indicate the potential for estrogenic compounds to persist in soil following biosolids application. Environ Toxicol Chem 2014;33:26-28. © 2013 SETAC [ABSTRACT FROM AUTHOR]

The article focuses on the consideration of cultural and spiritual perspectives in pharmaceuticals and personal care products (PPCPs) among indigenous people in Australia and New Zealand. It states that PPCPs has strong cultural manifestations among indigenous people through the so called Asian vulture crisis. It also explores the PPCPs workshop hosted by the Society of Environmental Toxicology and Chemistry (SETAC) in Adelaide, South Australia in 2012.

Laboratory biodegradation batch studies were performed to investigate the degradation behavior of six selected UV filters, namely benzophenone-3 ( BP-3), 3-(4-methylbenzylidene) camphor (4- MBC), Octyl 4-methoxycinnamate ( OMC), Octocrylene ( OC), 2-(3- t-butyl-2-hydroxy-5-methylphenyl)-5-chloro benzotriazole ( UV-326), and 2-(2'-hydroxy-5'-octylphenyl)-benzotriazole ( UV-329) in an aquifer microcosm (groundwater and aquifer sediment mixture) under aerobic and anaerobic (nitrate, sulfate, and Fe( III) reducing) conditions within 77 d. The results from the biodegradation experiments showed that the six UV filters were degraded well in the aquifer materials under different redox conditions. Rapid biodegradation was observed for BP-3 and OMC in the aquifer materials, with their half-lives of 1.5-8.8 d and 1.3-5.2 d, respectively. In most cases, aerobic conditions were more favorable for the degradation of the UV filters in aquifer materials. Relatively slow degradation of 4- MBC, UV-326, and UV-329 under anaerobic conditions was noted with their half-lives ranging between 47 d and 126 d, indicating potential persistence in anaerobic aquifers. The results showed that redox conditions could have significant effects on biodegradation of the UV filters in aquifers. [ABSTRACT FROM AUTHOR]

Studies were undertaken to assess sorption of seven endocrine-disrupting chemicals (EDCs), namely, estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethynylestradiol (EE2), bisphenol A (BPA), 4-tert-octyl phenol (4-t-OP), and 4-n-nonyl phenol (4-n-NP) on four soils (from sandy to clay soil) with different physicochemical properties and biodegradation of five EDCs (BPA, E2, EE2, 4-t-OP, and 4-n-NP) in a loam soil associated with wastewater reuse. We also characterized the biotransformation of E2 to E1 in the loam soil under aerobic and anaerobic conditions. Sorption test using a batch equilibrium method demonstrated that alkylphenols (4-t-OP and 4-n-NP) had the strongest sorption onto soils, followed by estrogens (EE2, E2, E1, E3) and BPA. This laboratory study showed that all five EDCs, including the degradation product E1, were degraded rapidly in the soil within 7 d under aerobic conditions. However, under anaerobic conditions in the soil, little or no degradation of the five EDCs was noted except for E2, which showed slow degradation during the 70-d study. The calculated half-lives for E2 under anaerobic conditions were 24 d in the soil. Estradiol was found to be biotransformed to E1 under both aerobic and anaerobic conditions. The study suggested that the five EDCs as well as E1, which may be present in reclaimed wastewater, would not persist in well-aerated soil. But these EDCs persisting in anaerobic soil may affect soil and groundwater quality and ecosystem. [ABSTRACT FROM AUTHOR]

Organophosphorus, pyrethroid and chloronicotinyl insecticides have been used to control termites in building structures in recent years. We investigated the degradation behaviour of three insecticides (bifenthrin, chlorpyrifos and imidacloprid) at termiticidal application rates under standard laboratory conditions (25 deg. C, 60% field moisture capacity and darkness) for 24 months. The study was carried out onone soil and two bedding materials (sand-dolomite and quarry sand), which are commonly used under housing in Australia. Experiments were also conducted to examine the effect of soil moisture on the degradation of these insecticides. Insecticide residues in the samples collected at different days after application were measured by high performance liquid chromatography (HPLC). The rate of degradation of bifenthrin and imidacloprid insecticides was adequately described by a first-order kinetic model (r2 = 0.93-0.97). However, chlorpyrifos degradation was biphasic, showing an initial faster degradation followed by a slower rate. Therefore, the degradation data during the slower phase only (after a two-month period) followed the first-order law (r2 = 0.95). Soil moisture had little effect on degradation of imidacloprid and bifenthrin. Among the three insecticides, bifenthrin and imidacloprid were most stable and chlorpyrifos the least. Chlorpyrifos showed a major loss (75-90%) of residue during the 24months incubation period. In the bedding materials, simultaneous accumulation of the primary metabolite of chlorpyrifos, TCP (3,5,6-trichloro-2-pyridinol) was observed. Hydrolysis appeared to have caused the observed rapid loss of chlorpyrifos, especially in the highly alkaline bedding materials (sand-dolomite and quarry sand). [ABSTRACT FROM AUTHOR]