Pan-European survey on the occurrence of selected polar organic persistent pollutants in ground water

Screening of emerging contaminants and priority substances (2008/105/EC) in reclaimed water for irrigation and groundwater in a volcanic aquifer (Gran Canaria, Canary Islands, Spain)

In semiarid regions, reclaimed water can be an important source of emerging pollutants in groundwater. In Gran Canaria Island, reclaimed water irrigation has been practiced for over thirty years and currently represents 8% of water resources. The aim of this study was to monitor contaminants of emerging concern and priority substances (2008/105/EC) in a volcanic aquifer in the NE of Gran Canaria where the Bandama Golf Course has been sprinkled with reclaimed water since 1976. Reclaimed water and groundwater were monitoring quarterly from July 2009 to May 2010. Only 43% of the 183 pollutants analysed were detected: 42 pharmaceuticals, 20 pesticides, 12 polyaromatic hydrocarbons, 2 volatile organic compounds and 2 flame retardants. The most frequent compounds were caffeine, nicotine, chlorpyrifos ethyl, fluorene, phenanthrene and pyrene. Concentrations were always below 50 ng L(-1), although some pharmaceuticals and one pesticide, cholrpyrifos ethyl, were occasionally detected at higher concentrations. This priority substance for surface water exceeded the maximum threshold (0.1 μg L(-1)) for pesticide concentration in groundwater (2006/118/EC). Sorption and degradation processes in soil account for more compounds being detected in reclaimed water than in groundwater, and that some contaminants were always detected in reclaimed water, but never in groundwater (flufenamic acid, propyphenazone, terbutryn and diazinon). Furthermore, erythromycin was always detected in reclaimed water (exceeding occasionally 0.1 μg L(-1)), and was detected only once in groundwater. In contrast, some compounds (phenylephrine, nifuroxazide and miconazole) never detected in reclaimed water, were always detected in groundwater. This fact and the same concentration range detected for the groups, regardless of the water origin, indicated alternative contaminant sources (septic tanks, agricultural practices and sewerage breaks). The widespread detection of high adsorption potential compounds, and the independence of concentration with origin and depths, indicates the existence of preferential flows phenomena as potential contamination route in volcanic fractured materials.

Survey of phthalates, alkylphenols, bisphenol A and herbicides in Spanish source waters intended for bottling

BACKGROUND, AIM AND SCOPE

Groundwaters and source waters are exposed to environmental pollution due to agricultural and industrial activities that can enhance the leaching of organic contaminants. Pesticides are among the most widely studied compounds in groundwater, but little information is available on the presence of phthalates, alkylphenols and bisphenol A. These compounds are used in pesticide formulations and represent an emerging family of contaminants due to their widespread environmental presence and endocrine-disrupting properties. Knowledge on the occurrence of contaminants in source waters intended for bottling is important for sanitary and regulatory purposes. So the aim of the present study was to evaluate the presence of phthalates, alkylphenols, triazines, chloroacetamides and bisphenol A throughout 131 Spanish water sources intended for bottling. Waters studied were spring waters and boreholes which have a protection diameter to minimize environmental contamination.

MATERIALS AND METHODS

Waters were solid-phase extracted (SPE) and analysed by gas chromatography coupled to mass spectrometry (GC-MS). Quality control analysis comprising recovery studies, blank analysis and limits of detection were performed.

RESULTS AND DISCUSSION

Using SPE and GC-MS, the 21 target compounds were satisfactorily recovered (77-124 %) and limits of quantification were between 0.0004 and 0.029 μg/L for pesticides, while for alkylphenols, bisphenol A and phthalates the limits of quantification were from 0.0018 μg/L for octylphenol to 0.970 μg/L for bis(2-ethylhexyl) phthalate. Among the 21 compounds analysed, only 9 were detected at levels between 0.002 and 1.115 μg/L. Compounds identified were triazine herbicides, alkylphenols, bisphenol A and two phthalates. Spring waters or shallow boreholes were the sites more vulnerable to contaminants. Eighty-five percent of the samples did not contain any of the target compounds.

CONCLUSIONS

Target compounds were detected in a very low concentration and only in very few samples. This indicates the good quality of source waters intended for bottling and the effectiveness of the protection measures adopted in Spain. None of the samples analysed exceeded the maximum legislated levels for drinking water both in Spain and in the European Union.

Controlled release and retarded leaching of pesticides by encapsulating in carboxymethyl chitosan /bentonite composite gel

A novel composite gel composed of carboxymethyl-chitosan (CM-chit) and bentonite (H-bent) was used as the carrier for encapsulating atrazine and imidacloprid to control their release in water and retard their leaching in soil. Strong interactions between CM-chit and H-bent in the composite were confirmed by FT-IR, and good dispersion of pesticides in the carrier was observed by SEM. According to the results of release experiments in water, the CM-chit/H-bent composite carrier showed double advantages of both encapsulation by the polymer and sorption by the bentonite. The time taken for 50 % of active ingredients to be released, t₅₀, was prolonged to 572 h for atrazine and 24 h for imidacloprid, respectively. The difference between the two pesticides on release behavior was related to their hydrophobicity and water solubility. Leaching experiments through a soil layer showed that this novel carrier reduced the amount of pesticides available for leaching, and would be useful for diminishing the environmental pollution of pesticides.

Atrazine-induced changes in the myocardial structure of peripubertal rats

The aim of the present study was to investigate the effect of atrazine (6-chloro-N(2)-ethyl-N(4)-isopropyl-1,3,5-triazine-2,4-diamine) on the left ventricle myocardium in juvenile/peripubertal male Wistar rats. Atrazine was administered orally at 50 or 200 mg/kg of body weight dose for 28 consecutive days. In order to assess possible structural alterations, tissue sections were examined histologically and then subjected to quantification analysis using stereological methods. The tissue specimens were routinely processed and stained with Mallory trichrome method in order to clearly distinguish muscle cells from the connective tissue components. A toluidine blue staining method was additionally used for the demonstration of mast cells. Statistically significant increase in length density and numerical density of capillaries were found at both the investigated doses of atrazine compared with the control. The increase in surface density and volume density of capillaries found at lower dosage of atrazine was significant in comparison with the control. The extensive mast cell degranulation was noted on the histological examination at both doses of the applied chemical. No significant changes were demonstrated for the stereological parameters of cardiomyocytes. Based on the available published data and the present results, it can be concluded that atrazine promoted angiogenesis in the rat myocardium, which might be partially mediated by mast cells.

National screening study on 10 perfluorinated compounds in raw and treated tap water in France

The occurrence of seven perfluoroalkyl carboxylates (PFCAs) and three perfluoroalkyl sulfonates (PFASs) was studied in raw- and treated-water samples from public water systems. Two sampling campaigns were performed during the summer of 2009 and in June 2010. Sampling was equally distributed across the 100 French departments. In total, 331 raw-water samples and 110 treated-water samples were analyzed during this study, representing approximately 20% of the national water supply flow. Concentrations of perfluorinated compounds (PFCs) were determined using automated solid-phase extraction and liquid chromatography-tandem mass spectrometry. In raw-water samples, the highest individual PFC concentration was 139 ng/L for perfluorohexanoic acid (PFHxA). The sum of all of the determined components was >100 ng/L at three sampling points (199, 117, and 115 ng/L). Of the investigated PFCs, perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid (PFOA), and PFHxA predominated (detected in 27%, 13%, 11%, and 7% of samples, respectively). Geographical variability was observed, with departments crossed by major rivers or with high population densities being more affected by PFC contamination. Compared with raw water, short-chain PFCAs, but not PFASs, were found in higher abundance in treated water. This difference suggests a relative effectiveness of certain water treatments for the elimination of PFASs but also a possible degradation of PFCA precursors by water-treatment processes. Our investigations did not show any heavily contaminated sites. In treated-water samples, the highest individual PFC concentration was 125 ng/L for PFHxA. The sum of all of the determined components was >100 ng/L at one sampling point (156 ng/L). The values observed for PFOS and PFOA in drinking water were not greater than the health-based drinking-water concentration protectives for lifetime exposure that have been defined for other countries.

Enhanced biodegradation of carbamazepine after UV/H2O2 advanced oxidation

Carbamazepine is one of the most persistent pharmaceutical compounds in wastewater effluents due to its resistance to biodegradation-based conventional treatment. Advanced oxidation can efficiently degrade carbamazepine, but the toxicity and persistence of the oxidation products may be more relevant than the parent. This study sets out to determine whether the products of advanced oxidation of carbamazepine can be biotransformed and ultimately mineralized by developing a novel methodology to assess these sequential treatment processes. The methodology traces the transformation products of the (14)C-labeled carbamazepine during UV/hydrogen peroxide advanced oxidation and subsequent biotransformation by mixed, undefined cultures using liquid scintillation counting and liquid chromatography with radioactivity, mass spectrometry, and UV detectors. The results show that the oxidation byproducts of carbamazepine containing a hydroxyl or carbonyl group can be fully mineralized by a mixed bacterial inoculum. A tertiary treatment approach that includes oxidation and biotransformation has the potential to synergistically mineralize persistent pharmaceutical compounds in wastewater treatment plant effluents. The methodology developed for this study can be applied to assess the mineralization potential of other persistent organic contaminants.

Proteomic analysis of 17β-estradiol degradation by Stenotrophomonas maltophilia

Microbial degradation plays a critical role in determining the environmental fate of steroid hormones, such as 17β-estradiol (E2). The molecular mechanisms governing the microbial transformation of E2 and its primary degradation intermediate, estrone (E1), are largely unknown. The objective of this study was to identify metabolism pathways that might be involved in microbial estrogen degradation. To achieve the objective, Stenotrophomonas maltophilia strain ZL1 was used as a model estrogen degrading bacterium and its protein expression level during E2/E1 degradation was studied using quantitative proteomics. During an E2 degradation experiment, strain ZL1 first converted E2 to E1 stoichiometrically. At 16 h E1 reached its peak concentration, and microbial growth started. At the same time, enzymes involved in certain catabolic and anabolic pathways were most highly expressed compared to the other time points tested. Among those enzymes, the ones involved in protein and lipid biosyntheses were observed to be particularly active. Based on the metabolite information from a previous study and the proteomic data from this study, we hypothesized that S. maltophilia strain ZL1 was able to convert E1 to amino acid tyrosine through ring cleavage on a saturated ring of the E1 molecule and then utilize tyrosine in protein biosynthesis.

Multi-residue analytical methods for the determination of pesticides and PPCPs in water by LC-MS/MS: a review

Residues of pesticides, pharmaceutical and personal care products (PPCPs) are contaminants of world-wide concern. Consequently, there is a growing need to develop reliable analytical methods, which enable rapid, sensitive and selective determination of these pollutants in environmental samples, at trace levels. In this paper, a review of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) based methods for the determination of pesticides and PPCPs in the environment is presented. Advanced aspects of current LC-MS/MS methodology, including sample preparation and matrix effects, are discussed.

Removing 17β-estradiol from drinking water in a biologically active carbon (BAC) reactor modified from a granular activated carbon (GAC) reactor

Estrogenic compounds in drinking water sources pose potential threats to human health. Treatment technologies are needed to effectively remove these compounds for the production of safe drinking water. In this study, GAC adsorption was first tested for its ability to remove a model estrogenic compound, 17β-estradiol (E2). Although GAC showed a relatively high adsorption capacity for E2 in isotherm experiments, it appeared to have a long mass transfer zone in a GAC column reactor, causing an early leakage of E2 in the effluent. With an influent E2 concentration of 20 μg/L, the GAC reactor was able to bring down effluent E2 to ≈ 200 ng/L. To further enhance E2 removal, the GAC reactor was converted to a biologically active carbon (BAC) reactor by promoting biofilm growth in the reactor. Under optimal operating conditions, the BAC reactor had an effluent E2 concentration of ≈ 50 ng/L. With the empty bed contact times tested, the reactor exhibited more robust E2 removal performance under the BAC operation than under the GAC operation. It is noted that estrone (E1), an E2 biodegradation intermediate, was frequently detected in reactor effluent during the BAC operation. Results from this study suggested that BAC could be an effective drinking water treatment process for E2 removal and in the meantime E1 accumulation needs to be addressed.

Electrochemical degradation of perfluorooctanoic acid (PFOA) by Ti/SnO2-Sb, Ti/SnO2-Sb/PbO2 and Ti/SnO2-Sb/MnO2 anodes

Electrochemical decomposition of environmentally persistent perfluorooctanoic acid (PFOA) in aqueous solution was investigated over Ti/SnO(2)-Sb, Ti/SnO(2)-Sb/PbO(2), and Ti/SnO(2)-Sb/MnO(2) anodes. The degradation of PFOA followed pseudo-first-order kinetics. The degradation ratios on Ti/SnO(2)-Sb, Ti/SnO(2)-Sb/PbO(2), and Ti/SnO(2)-Sb/MnO(2) anodes achieved 90.3%, 91.1%, and 31.7%, respectively, after 90 min electrolysis at an initial 100 mg/L PFOA concentration at a constant current density of 10 mA/cm(2) with a 10 mmol/L NaClO(4) supporting electrolyte solution. The defluorination rates of PFOA on these three anodes were 72.9%, 77.4%, 45.6%, respectively. The main influencing factors on electrochemical decomposition of PFOA over Ti/SnO(2)-Sb anode were evaluated, including current density (5-40 mA/cm(2)), initial pH value (3-11), plate distance (0.5-2.0 cm), and initial concentration (5-500 mg/L). The results indicated that PFOA (100 mL of 100 mg/L) degradation ratio and defluorination ratio achieved 98.8% and 73.9%, respectively, at the optimal conditions after 90 min electrolysis. Under this optimal condition, the degradation rate constant and the degradation half-life were 0.064 min(-1) and 10.8 min, respectively. The intermediate products including short-chain perfluorinated carboxylic acids (PFCAs, C(2) ≈ C(6)) and perfluorocarbons (C(2) ≈ C(7)) were detected by electrospray ionization (ESI) mass spectrum. A possible electrochemical degradation mechanism of PFOA including electron transfer, Kolbe decarboxylation, radical reaction, decomposition, and hydrolysis was proposed. The electrochemical technique could be employed to degrade PFOA from contaminated wastewater as well as to reduce the toxicity of PFOA.

Determination of C(5)-C(12) perfluoroalkyl carboxylic acids in river water samples in the Czech Republic by GC-MS after SPE preconcentration

A method employing solid phase extraction followed by gas chromatography-mass spectrometry with negative chemical ionization has been developed for determination of ultratrace concentrations of perfluoroalkyl carboxylic acids in river water. The effects of the experimental parameters, such as the pH, additions of NaCl and an ion-pairing agent (tetraethylammonium bromide) and the kind of the elution agent, on the efficiency of the test acid extraction have been studied. The analyte extraction recoveries and the limits of detection and determination have been found. The method developed has been tested on determinations of perfluoroalkyl carboxylic acids in the waters of the two largest Czech rivers, Vltava and Labe (Elbe). The best extraction results have been attained without any alteration of the sample pH, with an addition of tetrabutylammonium bromide (a concentration of 50 μg mL(-1) in the sample) and using methanol as the elution agent. Under these conditions, the recoveries of the test acids in the spiked real samples are within ranges from 60% to 104% and 53% to 111% for analyte concentration levels of 1.40 ng mL(-1) and 0.14 ng mL(-1), respectively, depending on the lengths of the perfluorinated chains of the acids. In general, the recovery decreases with increasing length of this chain. The method developed exhibits very low limits of detection and determination and the results are fully comparable with those obtained when using more expensive HPLC-MS/MS instrumentation. Typical values amount to tenths to tens of pg mL(-1) and units to one hundred pg mL(-1) for the limits of detection and determination, respectively; the measuring sensitivity increases with increasing length of the analyte chain. The analyzes of real samples from the Vltava and Elbe rivers have demonstrated that the results obtained are similar to the values published for contamination of the Elbe and other rivers in western and central Europe. The concentrations determined are of the order of units to tens of pg mL(-1) and the C(8)-C(10) acids occur most often.

Emerging organic contaminants in groundwater: A review of sources, fate and occurrence

Emerging organic contaminants (EOCs) detected in groundwater may have adverse effects on human health and aquatic ecosystems. This paper reviews the existing occurrence data in groundwater for a range of EOCs including pharmaceutical, personal care, 'life-style' and selected industrial compounds. The main sources and pathways for organic EOCs in groundwater are reviewed, with occurrence data for EOCs in groundwater included from both targeted studies and broad reconnaissance surveys. Nanogram-microgram per litre concentrations are present in groundwater for a large range of EOCs as well as metabolites and transformation products and under certain conditions may pose a threat to freshwater bodies for decades due to relatively long groundwater residence times. In the coming decades, more of these EOCs are likely to have drinking water standards, environmental quality standards and/or groundwater threshold values defined, and therefore a better understanding of the spatial and temporal variation remains a priority.

Seasonal distribution, source investigation and vertical profile of phenolic endocrine disrupting compounds in Dianchi Lake, China

Phenolic endocrine disrupting compounds, including nonylphenol-di-ethoxylate (NP2EO), nonylphenol-mono-ethoxylate (NP1EO), 4-nonylphenol (4-NP), bisphenol A (BPA), 4-cumylphenol (4-CP) and 4-tert-octylphenol (4-t-OP), were investigated in water, surface sediment and sediment cores in Dianchi Lake to track their seasonal distributions, pollution sources and historical trends. The concentrations of NP2EO, NP1EO, 4-NP, BPA, 4-CP and 4-t-OP were up to 295.14, 448.48, 45.28, 530.33, 8.96 and 21.37 ng L(-1) in water, and up to 297.11, 809.63, 4.58, 166.87, 3.62 and 40.69 ng g(-1) dry weight in surface sediment, respectively. Except BPA in water, concentrations of all the other phenolic compounds in both of the matrices were higher in January than in July, 2011. The concentrations decreased significantly with an increase in distance from the sampling locations which were adjacent to the urban areas (Kunming City, Chenggong City and Jinning City). The pollution of phenolic EDCs came mainly from industry, agriculture and daily life. The relationships between the concentrations of target compounds and the six water quality parameters were evaluated. There were significant positive correlations between concentrations of phenolic compounds in water and in surface sediment. For sediment cores, three clearly separated maxima occurred in segments 0-5 cm (the late 2000s), 5-10 cm (the early and mid of 2000s) and 20-25 cm (the mid of 1980s), respectively. NP2EO, NP1EO and BPA were the three dominant compounds in the lake.

Emerging pollutants in sewage, surface and drinking water in Galicia (NW Spain)

A monitoring programme was carried out on wastewater, surface and drinking water on the NW area of Spain during the four seasons of a year period (November 2007-September 2008). This study covered a series of emerging pollutants of different classes, including pharmaceuticals, neutral and acidic organophosphorus flame retardant/plasticizers (OPs), triclosan, phenoxy-herbicides, insect repellents and UV filters. From the total set of 53 compounds, 19 were found in raw wastewater with median concentrations higher than 0.1 μg L(-1). Among them, salicylic acid, ibuprofen and the UV filter benzophenone-4 (BP-4) were the most concentrated, exceeding the 1 μg L(-1) median value. Subsequently, 11 of these contaminants are not efficiently enough removed in the small WWTPs tested and their median concentrations in effluents still surpassed the 0.1 μg L(-1), so that they can spread through surface water. These chemicals are the pharmaceuticals naproxen, diclofenac and atenolol; the OPs tri(2-chloroethyl) phosphate (TCEP), tri(chloropropyl) phosphate (TCPP), tri-n-butyl phosphate (TnBP), diphenyl phosphate (DPhP) and diethylhexyl phosphate (DEHP); and the sulphonate UV filters BP-4 and 2-phenylbenzimidazole-5-sulphonic acid (PBSA). These OPs were then the dominant emerging pollutants occurring in surface and drinking water, where they are detected in the 20-200 ng L(-1) range. Pharmaceuticals and UV filters are typically below the 10 ng L(-1) level. Finally, herbicides were only detected in the last sampling campaign under the 100 ng L(-1) drinking water European Union limit.

Determination of perfluorochemicals in cow's milk using liquid chromatography-tandem mass spectrometry

This study describes a new method developed for detection of 10 different perfluorochemicals (PFCs) in cow's milk, seven perfluorinated carboxylates and three perfluorinated sulfonate salts. After attempting multiple methods employing both acidic and basic extractions, a basic extraction using 10 mM sodium hydroxide in methanol digestion along with weak anion-exchange solid-phase extraction was employed. Vortex mixing and varying sonication times were compared as part of sample processing. Results show that sonication during sample processing yield decreased recovery of longer chain perfluorinated carboxylates. The final method developed was used to determine the concentration of PFCs in 12 raw and 49 retail milk samples from across the United States. With the exception of a single raw milk sample obtained from a dairy farm that had applied PFC containing biosolids to its fields, there were no milk samples containing PFCs.

Review of risk from potential emerging contaminants in UK groundwater

This paper provides a review of the types of emerging organic groundwater contaminants (EGCs) which are beginning to be found in the UK. EGCs are compounds being found in groundwater that were previously not detectable or known to be significant and can come from agricultural, urban and rural point sources. EGCs include nanomaterials, pesticides, pharmaceuticals, industrial compounds, personal care products, fragrances, water treatment by-products, flame retardants and surfactants, as well as caffeine and nicotine. Many are relatively small polar molecules which may not be effectively removed by drinking water treatment. Data from the UK Environment Agency's groundwater screening programme for organic pollutants found within the 30 most frequently detected compounds a number of EGCs such as pesticide metabolites, caffeine and DEET. Specific determinands frequently detected include pesticides metabolites, pharmaceuticals including carbamazepine and triclosan, nicotine, food additives and alkyl phosphates. This paper discusses the routes by which these compounds enter groundwater, their toxicity and potential risks to drinking water and the environment. It identifies challenges that need to be met to minimise risk to drinking water and ecosystems.

Toxicological interactions of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) with selected pollutants

The combined toxicity of the perfluorinated surfactants perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and several pollutants (Hg(2+), Cd(2+), 2,4-D, propylparaben, mitomycin C and furazolidone) has been examined with a bioluminescent cyanobacterial toxicity test. Hg(2+), Cd(2+), mitomycin C and furazolidone could be included in the "Acute aquatic hazard" category established in the Regulation (EC) No 1272/2008 being "very toxic to aquatic life". Toxicological interactions of PFOA, PFOS with these pollutants in binary, ternary and multicomponent mixtures were studied using the combination-index method. PFOA and PFOS showed an antagonistic interaction at the whole range of effect levels, this may explain in part the finding that PFOA and PFOS interacted in an inverse way with the organic pollutants; the relative hydrophobicity of the tested compounds would also explain this interaction pattern. The interaction of both PFOS and PFOA with heavy metals was mostly antagonistic, decreasing metal toxicity. With increasing complexity of the mixtures, the CI method predicted synergism at low to very low levels of effect; pollutant combinations at their mixture NOECs were tested and confirmed the predicted synergism.

Occurrence and biodegradation of nonylphenol in the environment

Nonylphenol (NP) is an ultimate degradation product of nonylphenol polyethoxylates (NPE) that is primarily used in cleaning and industrial processes. Its widespread use has led to the wide existence of NP in various environmental matrices, such as water, sediment, air and soil. NP can be decreased by biodegradation through the action of microorganisms under aerobic or anaerobic conditions. Half-lives of biodegradation ranged from a few days to almost one hundred days. The degradation rate for NP was influenced by temperature, pH and additions of yeast extracts, surfactants, aluminum sulfate, acetate, pyruvate, lactate, manganese dioxide, ferric chloride, sodium chloride, hydrogen peroxide, heavy metals, and phthalic acid esters. Although NP is present at low concentrations in the environment, as an endocrine disruptor the risks of long-term exposure to low concentrations remain largely unknown. This paper reviews the occurrence of NP in the environment and its aerobic and anaerobic biodegradation in natural environments and sewage treatment plants, which is essential for assessing the potential risk associated with low level exposure to NP and other endocrine disruptors.

Impact of vegetated filter strips on sorbed herbicide concentrations and sorption equilibrium in agricultural plots

The objective was to investigate the impact of vegetated filter strips on exported atrazine and deethylatrazine concentrations [dissolved and sorbed to eroded sediments (>1.5 μm)], the deethylatrazine to atrazine ratio in water and sediments, the ratio of sorbed to dissolved herbicides in runoff and subsurface infiltration as well as field equilibrium state under natural climate during two seasons. We hypothesize that sorption equilibrium was not achieved in 2004 because of the short delay (<24 h) between herbicide application and the first rain event. In 2005, observations suggest that possible changing sorption equilibrium conditions were reached (20 days after atrazine application), especially for eroded sediments submitted to changing environmental conditions in subsurface. If confirmed by other experiments, this will raise the question of the representativeness of laboratory-determined soil sorption coefficients to predict the fate of pesticides.

Development of a new time-integrative sampler using in situ solvent extraction

Despite the great success of time-weighted average passive sampling of hydrophobic contaminants, such as PCBs and PAHs, the sampling of polar organic compounds still presents a challenge because the equilibrium between water and most sampling phases is attained in a relatively short time. In this study, we proposed a new time-integrative sampler using in situ solvent extraction (TISIS) for polar organic chemicals. The sampler was composed of a 15 cm poly(dimethylsiloxane) (PDMS) tubing, with an internal diameter of 0.5 mm and wall thickness of 0.5 mm, through which an extraction solvent (acetonitrile) was passed. Four polar organic contaminants, caffeine, atrazine, diuron and 17α-ethynylestradiol, were chosen for the evaluation of the performance of the sampler. Without the use of in situ solvent extraction, the PDMS tubing when exposed to a constant aqueous concentration of the four model compounds was able to linearly accumulate those compounds for less than 12 h and equilibrium between the PDMS tubing and water was attained in 2 d under our laboratory conditions. However, TISIS when exposed to a constant aqueous concentration was able to linearly accumulate all the model compounds without any exposure time limitation. The measured sampling rates at three different extraction flow rates (0.2, 0.5, 1.5 mL min(-1)) were similar, regardless of the chemicals, indicating that the overall mass transfer from aqueous solution to the extraction solvent was most likely dominated by partitioning to the PDMS tubing and the internal diffusion within PDMS. In addition, a pulsed exposure experiment confirmed that TISIS operated in a time-integrative mode when the environmental concentration was highly fluctuated.

Optimization of a dispersive liquid-liquid microextraction method for the analysis of benzotriazoles and benzothiazoles in water samples

A simple and rapid dispersive liquid-liquid microextraction method has been developed for the determination of 11 benzotriazoles and benzothiazoles in water samples. Tri-n-butylphosphate (TBP) was used as extractant, thus avoiding the use of toxic water-immiscible chlorinated solvents. The influence of several variables (e.g., type and volume of dispersant and extraction solvents, sample pH, ionic strength, etc.) on the performance of the sample preparation step was systematically evaluated. Analytical determinations were carried out by high-performance liquid chromatography with fluorescence and UV detection and liquid chromatography-electrospray ionization-tandem mass spectrometry. The optimized method exhibited a good precision level with relative standard deviation values between 3.7% and 8.4%. Extraction yields ranging from 67% to 97% were obtained for all of these considered compounds. Finally, the proposed method was successfully applied to the analysis of benzotriazoles and benzothiazoles in real water samples (tap, river, industrial waters, and treated and raw wastewaters).

[Biomonitoring of human exposure to triazine herbicides]

Triazine herbicides are very common and only 0.1 % reach the target pests, while the rest moves into other environmental compartments. Their fate in the environment depends on their movement through the air, water, and soil and on the rate of their degradation or transformation. Triazine compounds may be transformed by water, microorganisms, and sunlight. Widespread use and persistence of triazine herbicides in soil has resulted in contamination of surface, drinking, and even rain water with parent compounds and degradation products, posing a risk to the general population.The metabolism and effects of triazine herbicides have been studied in experimental animals and in experiments in vitro. There are only a few studies of their metabolism and excretion in humans. Agricultural and manufacturing workers are exposed to triazines during application and production. Human exposure is monitored by determining parent compounds and their metabolites in urine. Due to the low concentrations of urinary metabolites in occupationally exposed persons, very sensitive analytical methods are required. This paper describes the structure and properties of symmetric triazine herbicides, their metabolism, and effects in humans and animals and the levels of these compounds in the urine of occupationally exposed persons.

Occurrence, distribution and fluxes of benzotriazoles along the German large river basins into the North Sea

Benzotriazole (BT) and tolyltriazole (TT) are high production volume chemicals which are used in various industrial and household applications. In this study, the distribution of benzotriazoles in the estuaries of different rivers of central Europe and in the North Sea was analyzed by solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (HPLC-MS/MS). BT as well as TT was detected in all water samples. The concentrations for total benzotriazoles (BTs) ranged from 1.7 to 40 ng/L in the North Sea in costal areas. Concentrations in rivers are from 200 to 1250 ng/L, respectively. The mass flux of total benzotriazoles from the major rivers of central Europe into the North Sea was calculated to 78 t/a, dominated by the Rhine with an individual flux of 57 t/a of BTs. The analysis of the distribution profile in the North Sea showed that the decrease of the concentration was mostly caused by dilution and that the benzotriazoles are poorly degradable in the North Sea. This paper presents the first report of benzotriazoles in the marine environment.

Perfluorinated compounds in surface waters and WWTPs in Shenyang, China: mass flows and source analysis

Concentrations of 10 perfluorinated chemicals (PFCs) were investigated in the Hun River (HR), four canals, ten lakes, and influents and effluents from four main municipal wastewater treatment plants (WWTPs) in Shenyang, China. Mass flows of four main PFCs were calculated to elucidate the contribution from different sections of the HR. Overall, perfluorooctanoic acid (PFOA) and perfluorohexanoic acid (PFHxA) were the major PFCs in the HR, with ranges of 2.68-9.13 ng/L, and 2.12-11.3 ng/L, respectively, while perfluorooctane sulfonate (PFOS) was detected at lower levels, ranging from 0.40 to 3.32 ng/L. The PFC concentrations in the HR increased after the river passes through two cities (Shenyang and Fushun), indicating cities are an important contributor for PFCs. Mass flow analysis in the HR revealed that PFC mass flows from Fushun are 1.65-5.50 kg/year for C6-C8 perfluorinated acids (PFCAs) and 1.29 kg/year for PFOS, while Shenyang contributed 2.83-5.18 kg C6-C8 PFCAs/year, and 3.65 kg PFOS/year. The concentrations of PFCs in four urban canals were higher than those in the HR, with the maximum total PFCs of 240 ng/L. PFOA and PFOS showed different trends along these canals, suggesting different sources for the two PFCs. Total PFCs in ten lakes from Shenyang were at low levels, with the greatest concentration (56.2 ng/L) detected in a heavily industrialized area. The PFC levels in WWTP effluents were higher than those in surface waters with concentrations ranging from 18.4 to 41.1 ng/L for PFOA, and 1.69-3.85 ng/L for PFOS. Similar PFC profiles between effluents from WWTPs and urban surface waters were found. These results indicate that WWTPs are an important PFC source in surface water. Finally, we found that the composition profiles of PFCs in surface waters were similar to those in tap water, but not consistent with those in adult blood from Shenyang. The calculation on total daily intake of PFOS by adults from Shenyang showed that the contribution of drinking water to human exposure was minor.

Perfluoroalkyl and polyfluoroalkyl substances in the environment: terminology, classification, and origins

The primary aim of this article is to provide an overview of perfluoroalkyl and polyfluoroalkyl substances (PFASs) detected in the environment, wildlife, and humans, and recommend clear, specific, and descriptive terminology, names, and acronyms for PFASs. The overarching objective is to unify and harmonize communication on PFASs by offering terminology for use by the global scientific, regulatory, and industrial communities. A particular emphasis is placed on long-chain perfluoroalkyl acids, substances related to the long-chain perfluoroalkyl acids, and substances intended as alternatives to the use of the long-chain perfluoroalkyl acids or their precursors. First, we define PFASs, classify them into various families, and recommend a pragmatic set of common names and acronyms for both the families and their individual members. Terminology related to fluorinated polymers is an important aspect of our classification. Second, we provide a brief description of the 2 main production processes, electrochemical fluorination and telomerization, used for introducing perfluoroalkyl moieties into organic compounds, and we specify the types of byproducts (isomers and homologues) likely to arise in these processes. Third, we show how the principal families of PFASs are interrelated as industrial, environmental, or metabolic precursors or transformation products of one another. We pay particular attention to those PFASs that have the potential to be converted, by abiotic or biotic environmental processes or by human metabolism, into long-chain perfluoroalkyl carboxylic or sulfonic acids, which are currently the focus of regulatory action. The Supplemental Data lists 42 families and subfamilies of PFASs and 268 selected individual compounds, providing recommended names and acronyms, and structural formulas, as well as Chemical Abstracts Service registry numbers.

Screening of pharmaceuticals and hormones at the regional scale, in surface and groundwaters intended to human consumption

As part of a regional screening to evaluate the risk, for the health of populations, to certain classes of emerging substances, several families of pharmaceuticals and hormones were looked for in waters intended to drinking. Thus, 52 substances were investigated in 71 surface waters and 70 groundwaters. Results indicate that no water was free of pollutants, regardless of its origin (surface or groundwater) and the season of collect. The pharmaceuticals most frequently detected and with the highest concentration levels were salicylic acid, carbamazepine and acetaminophen. Among hormones, testosterone, androstenedione and progesterone were detected in almost all the samples. Globally the groundwaters were less contaminated than surface waters in regards pharmaceuticals frequencies and levels. On the other side, androgens and progestagens were present with comparable frequencies and levels in both compartments. The risk linked to the presence of these substances on human health is discussed.

Identification of perfluoroalkyl acid sources in Swiss surface waters with the help of the artificial sweetener acesulfame

Anthropogenic perfluorinated compounds (PFCs), especially the perfluoroalkyl acids (PFAAs) are ubiquitously found in surface waters around the globe. Emissions from households, industries and also atmospheric transport/deposition are discussed as the possible sources. In this study, these sources are evaluated using Switzerland as the study area. Forty-four surface water locations in different rivers and an Alpine lake were investigated for 14 PFAAs, four precursors and acesulfame, an artificial sweetener used as a population marker. Concentrations of individual PFAAs were generally low, between 0.02 and 10 ng/L. Correlation analysis showed that some PFAAs concentrations correlated well with population and less with catchment area, indicating that emissions from population, i.e., from consumer products, is the most important source to surface waters in Switzerland. The correlation with the population marker acesulfame confirmed this observation but highlighted also a few elevated PFAA levels, some of which could be attributed to industrial emissions.

Still present after all these years: persistence plus potential toxicity raise questions about the use of atrazine

As one of the worlds' most heavily applied herbicides, atrazine is still a matter of controversy. Since it is regularly found in ground and drinking water, as well as in sea water and the ice of remote areas, it has become the subject of continuous concern due to its potential endocrine and carcinogenic activity. Current findings prove long-held suspicions that this compound persists for decades in soil. Due to the high amount applied annually all over the world, the soil burden of this compound is considered to be tremendous, representing a potential long-term threat to the environment. The persistence of chemicals such as atrazine has long been underestimated: Do we need to reconsider the environmental risk?

Current approaches to trace analysis of pharmaceuticals and personal care products in the environment

A large number of xenobiotics including pharmaceuticals and personal care products are continuously released into the environment. Effluents from sewage treatment plants are well known to be the major source for introduction of pharmaceuticals and personal care products into the aquatic system. In recent years, reliable methods have been established for residue analysis of these pollutants down to low ng/L levels. In this review, the different approaches to their trace determination are reviewed with special attention being paid to sample preparation procedures, state-of-the-art high-performance separation methods hyphenated with mass spectrometry, and immunochemical methods.