An overview on the advanced oxidation processes applied for the treatment of water pollutants defined in the recently launched Directive 2013/39/EU

Environmental pollution is a recognized issue of major concern since a wide range of contaminants has been found in aquatic environment at ng L^− 1 to μg L^− 1 levels. In the year 2000, a strategy was defined to identify the priority substances concerning aquatic ecosystems, followed by the definition of environmental quality standards (EQS) in 2008. Recently it was launched the Directive 2013/39/EU that updates the water framework policy highlighting the need to develop new water treatment technologies to deal with such problem. This review summarizes the data published in the last decade regarding the application of advanced oxidation processes (AOPs) to treat priority compounds and certain other pollutants defined in this Directive, excluding the inorganic species (cadmium, lead, mercury, nickel and their derivatives).The Directive 2013/39/EU includes several pesticides (aldrin, dichlorodiphenyltrichloroethane, dicofol, dieldrin, endrin, endosulfan, isodrin, heptachlor, lindane, pentachlorophenol, chlorpyrifos, chlorfenvinphos, dichlorvos, atrazine, simazine, terbutryn, diuron, isoproturon, trifluralin, cypermethrin, alachlor), solvents (dichloromethane, dichloroethane, trichloromethane and carbon tetrachloride), perfluorooctane sulfonic acid and its derivatives (PFOS), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), nonylphenol and octylphenol, as well as the three compounds included in the recommendation for the first watch list of substances (diclofenac, 17-alpha-ethinylestradiol (EE2) and 17-beta-estradiol (E2)). Some particular pesticides (aclonifen, bifenox, cybutryne, quinoxyfen), organotin compounds (tributyltin), dioxins and dioxin-like compounds, brominated diphenylethers, hexabromocyclododecanes and di(2-ethylhexyl)phthalate are also defined in this Directive, but studies dealing with AOPs are missing.AOPs are recognized tools to destroy recalcitrant compounds or, at least, to transform them into biodegradable species. Diuron (a phenylurea herbicide) and atrazine (from the triazine chemical class) are the most studied pesticides from Directive 2013/39/EU. Fenton-based processes are the most frequently applied to treat priority compounds in water and their efficiency typically increases with the operating temperature as well as under UV or solar light. Heterogeneous photocatalysis is the second most used treatment to destroy pollutants defined in the Directive. Ozone alone promotes the partial oxidation of pollutants, and an increase in the effluent biodegradability, but complete mineralization of pollutants is difficult. To overcome this drawback, ozonation has been combined with heterogeneous catalysts, addition of H₂O₂, other AOPs (such as photocatalysis) or membrane technologies.     

Health impact and damage cost assessment of pesticides in Europe

Health impacts from pesticide use are of continuous concern in the European population, requiring a constant evaluation of European pesticide policy. However, health impacts have never been quantified accounting for specific crops contributing differently to overall human exposure as well as accounting for individual substances showing distinct environmental behavior and toxicity. We quantify health impacts and related damage costs from exposure to 133 pesticides applied in 24 European countries in 2003 adding up to almost 50% of the total pesticide mass applied in that year. Only 13 substances applied to 3 crop classes (grapes/vines, fruit trees, vegetables) contribute to 90% of the overall health impacts of about 2000 disability-adjusted life years in Europe per year corresponding to annual damage costs of 78 million Euro. Considering uncertainties along the full impact pathway mainly attributable to non-cancer dose–response relationships and residues in treated crops, we obtain an average burden of lifetime lost per person of 2.6 hours (95% confidence interval between 22 seconds and 45.3 days) or costs per person over lifetime of 12 Euro (95% confidence interval between 0.03 Euro and 5142 Euro), respectively. 33 of the 133 assessed substances accounting for 20% of health impacts in 2003 are now banned from the European market according to current legislation. The main limitation in assessing human health impacts from pesticides is related to the lack of systematic application data for all used substances. Since health impacts can be substantially influenced by the choice of pesticides, the need for more information about substance application becomes evident.     

Protective glove use and hygiene habits modify the associations of specific pesticides with Parkinson's disease

Pesticides have been associated with Parkinson's disease (PD), and protective gloves and workplace hygiene can reduce pesticide exposure. We assessed whether use of gloves and workplace hygiene modified associations between pesticides and PD. The Farming and Movement Evaluation (FAME) study is a nested case–control study within the Agricultural Health Study. Use of protective gloves, other PPE, and hygiene practices were determined by questionnaire (69 cases and 237 controls were included). We considered interactions of gloves and hygiene with ever-use of pesticides for all pesticides with ≥ 5 exposed and unexposed cases and controls in each glove-use stratum (paraquat, permethrin, rotenone, and trifluralin). 61% of respondents consistently used protective gloves and 87% consistently used ≥ 2 hygiene practices. Protective glove use modified the associations of paraquat and permethrin with PD: neither pesticide was associated with PD among protective glove users, while both pesticides were associated with PD among non-users (paraquat OR 3.9 [95% CI 1.3, 11.7], interaction p = 0.15; permethrin OR 4.3 [95% CI 1.2, 15.6] interaction p = 0.05). Rotenone was associated with PD regardless of glove use. Trifluralin was associated with PD among participants who used < 2 hygiene practices (OR 5.5 [95% CI 1.1, 27.1]) but was not associated with PD among participants who used 2 or more practices (interaction p = 0.02). Although sample size was limited in the FAME study, protective glove use and hygiene practices appeared to be important modifiers of the association between pesticides and PD and may reduce risk of PD associated with certain pesticides.     

Farm residence and reproductive health among boys in rural South Africa

BackgroundFew studies have investigated reproductive health effects of contemporary agricultural pesticides in boys.ObjectivesTo determine the association between pesticide exposure and reproductive health of boys.MethodsWe conducted a cross-sectional study in rural South Africa of boys living on and off farms. The study included a questionnaire (demographics, general and reproductive health, phyto-estrogen intake, residential history, pesticide exposures, exposures during pregnancy); and a physical examination that included sexual maturity development ratings; testicular volume; height, weight, body mass index; and sex hormone concentrations.ResultsAmong the 269 boys recruited into the study, 177 (65.8%) were categorized as farm (high pesticide exposures) and 98 (34.2%) as non-farm residents (lower pesticide exposures). Median ages of the two groups were 11.3 vs 12.0 years, respectively (p < 0.05). After controlling for confounders that included socioeconomic status, farm boys were shorter (regression coefficient (RC) = − 3.42 cm; 95% confidence interval (CI): − 6.38 to − 0.45 cm) and weighed less (RC = − 2.26 kg; CI: − 4.44 to − 0.75 kg). The farm boys also had lower serum lutenizing hormone (RC = − 0.28 IU/L; CI: − 0.48 to − 0.08 IU/L), but higher serum oestradiol (RC = 8.07 pmol/L; CI: 2.34–13.81 pmol/L) and follicle stimulating hormone (RC = 0.63 IU/L; CI: 0.19–1.08 U/L).ConclusionsOur study provides evidence that farm residence is associated with adverse growth and reproductive health of pubertal boys which may be due to environmental exposures to hormonally active contemporary agricultural pesticides.     

Potential water saving through changes in European diets

This study quantifies the water footprint of consumption (WF_cons) regarding agricultural products for three diets – the current diet (REF), a healthy diet (HEALTHY) and a vegetarian diet (VEG) – for the four EU zones WEST, NORTH, SOUTH and EAST. The WF_cons related to the consumption of agricultural products (4265 l per capita per day or lcd) accounts for 89% of the EU's total WF_cons (4815 lcd). The effect of diet has therefore an essential impact on the total WF_cons. The current zonal WF_cons regarding agricultural products is: 5875 lcd (SOUTH), 4053 lcd (EAST), 3761 lcd (WEST) and 3197 lcd (NORTH). These differences are the result of different consumption behaviours as well as different agricultural production methods and conditions. From the perspective of a healthy diet based on regional dietary guidelines, the intake of several product groups (sugar, crop oils, animal fats and meat) should be decreased and increased for others (vegetables, fruit). The WF_cons regarding agricultural products for the alternative diets are the following: HEALTHY 4110 lcd (− 30%) and VEG 3476 lcd (− 41%) for SOUTH; HEALTHY 3606 lcd (− 11%) and VEG 2956 lcd (− 27%) for EAST; HEALTHY 2766 lcd (− 26%) and VEG 2208 lcd (− 41%) for WEST; HEALTHY 3091 lcd (− 3%) and VEG 2166 lcd (− 32%) for NORTH. Both the healthy and vegetarian diets thus result – consistent for all zones – in substantial WF_cons reductions. The largest reduction takes place for the vegetarian diet. Indeed, a lot of water can be saved by EU citizens by a change in their diet.     

Route-specific daily uptake of organochlorine pesticides in food,dust, and air by Shanghai residents,China

Dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexanes (HCHs) are widely detected in the environment, although they have been banned in China since 1980s. To better understand the route-specific daily uptake of the pesticides by humans, a total of 322 food, dust, and air samples were collected in Shanghai, China, during 2008–2011. The median concentrations were 0.2–126.6 and 0.03–1.6 ng/g wet weight for DDTs (DDT and its metabolites) and HCHs, respectively, in different types of foods. The values in dust (indoors and outdoors) were 5.7–29.8 and 1.3–5.4 ng/g, and 13.9 × 10^− 3 and 2.6 × 10^− 3 ng/m³ in air (gas + particle) for DDTs and HCHs, respectively. The daily uptake of a pesticide by humans was calculated via the pesticide intake multiplied by its uptake efficiency. The uptake efficiencies of DDTs and HCHs in food through human intestines were estimated using bioaccessibility measured via an in vitro method simulating the human gastrointestinal digestion process. The total daily uptakes of DDTs and HCHs through three routes (i.e., ingestion, inhalation, and dermal contact) were 79.4 and 4.9 ng/day, respectively, for children, and 131.1 and 8.0 ng/day, respectively, for adults. Ingestion via food and dust was the main route of human exposure to the pesticides, and the daily uptake of the pesticides via food consumption accounted for 95.0–99.2% of the total.     

Persistent organic pollutants in the Scheldt estuary: Environmental distribution and bioaccumulation

Levels of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs) were determined in the sediment and several species (European flounder, Platichthys flesus; common sole, Solea solea; Chinese mitten crab, Eriocheir sinensis; shore crab, Carcinus maenas; brown shrimp, Crangon crangon; blue mussel, Mytilus edulis and bristle worms, Polychaeta) from 7 locations in the Scheldt estuary (SE, the Netherlands–Belgium). Overall POP levels in the sediment were low. The average PCB and PBDE concentrations were respectively 31.5 and 115 ng/g dry weight (dw). Highest sediment loads were measured in the vicinity of Antwerp (368 ng PCBs/g dw), a location with intense harbor and industrial activities. Pollution concentrations in the tissues of biota were species-specific. Blue mussels contained the highest lipid concentrations (2.74 ± 0.55%) and reached the highest contamination levels (from 287 to 1688 ng PCBs/g ww, from 2.09 to 12.4 ng PBDEs/g ww). Lowest tissue loads were measured in brown shrimp (from 3.27 to 39.9 ng PCBs/g ww, from 0.05 to 0.47 ng PBDEs/g ww). The PCB congener profile in most of the species was similar with the pattern found in the sediment. PCB 153 was the most abundant congener (16.5–25.7% in biota, 10.4% in sediment). In the sediment, the total amount of PBDEs consisted for more than 99% of BDE 209. Congener BDE 47 had the highest concentrations in all sampled species (38.5–70.1%). Sediment POP loadings and tissue concentrations were poorly correlated, indicating that a simple linear or non-linear relationship is insufficient to describe this relationship, possible caused by the complexity of the bioaccumulation processes and the variability in exposure. Because of the high PCB levels, regular consumption of fish and seafood, especially mussels, from the Scheldt estuary should be avoided.     

Organophosphate pesticide exposure and perinatal outcomes in Shanghai,China

Although pesticide use is widespread in China, little is known about levels of exposure to organophosphate pesticides in the population and its potential adverse health effects. We investigated levels of organophosphate exposure in pregnant women and the association between organophosphate exposure and perinatal outcomes in Shanghai, China, by enrolling 187 healthy pregnant women between September 2006 and January 2007. Pesticide exposure was assessed by a questionnaire administered to the mothers in the hospital after delivery as well as by analyses of maternal urinary nonspecific metabolites of organophosphate pesticides (dimethyl and diethyl phosphates). Information on birth weight and length was collected from medical records. Geometric means of metabolites were 25.75 μg/L for dimethylphosphate (DMP); 11.99 μg/L for dimethylthiophosphate (DMTP); 9.03 μg/L for diethylphosphate (DEP); and 9.45 μg/L for diethyldithiophosphate (DETP). We found that a log unit increase in urinary DEP was associated with a decrease in gestational duration in girls by 1.79 weeks. [ß_adjusted = − 1.79 weeks per log₁₀ unit increase; 95% confidence interval (CI), −2.82 to − 0.76; p = 0.001]. These data suggest that high pesticide level might adversely affect duration of gestation although this association was not present among boys. No associations for any of the organophosphate exposure measures were present for birth weight and length, suggesting that organophosphate pesticides may have no effects on fetal growth. Given that maternal urine pesticide levels in Shanghai were much higher than those reported in developed countries, more studies on the effects of in utero organophosphate exposure on fetal growth and child neurodevelopment are warranted.     

Association between background exposure to organochlorine pesticides and the risk of cognitive impairment: A prospective study that accounts for weight change

BackgroundBackground exposure to organochlorine (OC) pesticides was recently linked to cognitive impairment and dementia in cross-sectional and case–control studies. This prospective study was performed to evaluate if OC pesticides at baseline are associated with the future risk of cognitive impairment in elderly, with particular focus on weight change.MethodsPlasma concentrations of 3 OC pesticides (p,p′-DDE, trans-nonachlor, and hexachlorobenzene) were measured among 989 men and women aged 70 years in the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS). Cognitive impairment was validated by reviewing medical records. During the ten year follow-up, cognitive impairment was developed in 75 subjects. When weight change from age 70 to 75 was considered in analyses, elderly with incident cases before age 75 were excluded to keep the prospective perspective, leaving 795 study subjects and 44 incident cases.ResultsThe summary measure of 3 OC pesticides predicted the development of cognitive impairment after adjusting for covariates, including weight change. Compared to subjects with OC pesticides < 25th percentile, adjusted hazard ratios (HRs) in those with 25th–<75th and ≥ 75th percentiles were 3.5 (95% confidence interval: 1.5–8.5) and 3.2 (1.1–7.6), respectively (P_trend = 0.04). Among 506 subjects who maintained or gained body weight, adjusted HRs were 6.9 and 11.6 (1.4–92.6) among the elderly in the 25th–<75th and ≥ 75th percentiles compared to < 25th percentile (P_trend < 0.01).ConclusionsThis prospective study demonstrates that background exposure to OC pesticides are linked to the risk of developing cognitive impairment in elderly. The role of the chronic exposure to low dose OC pesticides in the development of dementia should be further evaluated in other populations.     

Prenatal exposure to multiple pesticides is associated with auditory brainstem response at 9 months in a cohort study of Chinese infants

BackgroundPesticides are associated with poorer neurodevelopmental outcomes, but little is known about the effects on sensory functioning.MethodsAuditory brainstem response (ABR) and pesticide data were available for 27 healthy, full-term 9-month-old infants participating in a larger study of early iron deficiency and neurodevelopment. Cord blood was analyzed by gas chromatography–mass spectrometry for levels of 20 common pesticides. The ABR forward-masking condition consisted of a click stimulus (masker) delivered via ear canal transducers followed by an identical stimulus delayed by 8, 16, or 64 milliseconds (ms). ABR peak latencies were evaluated as a function of masker-stimulus time interval. Shorter wave latencies reflect faster neural conduction, more mature auditory pathways, and greater degree of myelination. Linear regression models were used to evaluate associations between total number of pesticides detected and ABR outcomes. We considered an additive or synergistic effect of poor iron status by stratifying our analysis by newborn ferritin (based on median split).ResultsInfants in the sample were highly exposed to pesticides; a mean of 4.1 pesticides were detected (range 0–9). ABR Wave V latency and central conduction time (CCT) were associated with the number of pesticides detected in cord blood for the 64 ms and non-masker conditions. A similar pattern seen for CCT from the 8 ms and 16 ms conditions, although statistical significance was not reached. Increased pesticide exposure was associated with longer latency. The relation between number of pesticides detected in cord blood and CCT depended on the infant's cord blood ferritin level. Specifically, the relation was present in the lower cord blood ferritin group but not the higher cord blood ferritin group.ConclusionsABR processing was slower in infants with greater prenatal pesticide exposure, indicating impaired neuromaturation. Infants with lower cord blood ferritin appeared to be more sensitive to the effects of prenatal pesticide exposure on ABR latency delay, suggesting an additive or multiplicative effect.     

Widespread contamination of wildflower and bee-collected pollen with complex mixtures of neonicotinoids and fungicides commonly applied to crops

There is considerable and ongoing debate as to the harm inflicted on bees by exposure to agricultural pesticides. In part, the lack of consensus reflects a shortage of information on field-realistic levels of exposure. Here, we quantify concentrations of neonicotinoid insecticides and fungicides in the pollen of oilseed rape, and in pollen of wildflowers growing near arable fields. We then compare this to concentrations of these pesticides found in pollen collected by honey bees and in pollen and adult bees sampled from bumble bee colonies placed on arable farms. We also compared this with levels found in bumble bee colonies placed in urban areas. Pollen of oilseed rape was heavily contaminated with a broad range of pesticides, as was the pollen of wildflowers growing nearby. Consequently, pollen collected by both bee species also contained a wide range of pesticides, notably including the fungicides carbendazim, boscalid, flusilazole, metconazole, tebuconazole and trifloxystrobin and the neonicotinoids thiamethoxam, thiacloprid and imidacloprid. In bumble bees, the fungicides carbendazim, boscalid, tebuconazole, flusilazole and metconazole were present at concentrations up to 73 nanogram/gram (ng/g). It is notable that pollen collected by bumble bees in rural areas contained high levels of the neonicotinoids thiamethoxam (mean 18 ng/g) and thiacloprid (mean 2.9 ng/g), along with a range of fungicides, some of which are known to act synergistically with neonicotinoids. Pesticide exposure of bumble bee colonies in urban areas was much lower than in rural areas. Understanding the effects of simultaneous exposure of bees to complex mixtures of pesticides remains a major challenge.     

Biomarkers of pesticide exposure and diabetes in the 1999–2004 National Health and Nutrition Examination Survey

The associations of 8 pesticides and pesticide metabolites with total diabetes (diagnosed and undiagnosed) and pre-diabetes (glycohemoglobin 5.7–6.4%) were evaluated using the National Health and Nutrition Examination Survey (NHANES), 1999–2004. Six of the pesticides were found to be associated with total diabetes in separate adjusted logistic regressions. These pesticides and pesticide metabolites were beta-hexachlorocyclohexane, p,p′-DDE, p,p′-DDT, oxychlordane, trans-nonachlor, and heptachlor epoxide. When the number of compounds elevated was tested, 4 or more, of the 6, elevated had an odds ratio of 4.99 (95% CI 1.97–12.61) compared to none elevated. When the 6 compounds were tested together in a single combined adjusted logistic regression only oxychlordane, a metabolite of chlordane, and heptachlor epoxide, a metabolite of heptachlor, were significantly associated with total diabetes. In the combined adjusted logistic regression, oxychlordane ≥ 14.5 ng/g lipid adjusted had an odds ratios of 1.90 (95% CI 1.09–3.32) compared to oxychlordane < 14.5 ng/g lipid adjusted, and heptachlor epoxide ≥ 14.6 ng/g lipid adjusted had an odds ratio of 1.70 (95% CI 1.16–2.49) compared to heptachlor epoxide < 14.6 ng/g lipid adjusted. Heptachlor epoxide and p,p′-DDT were significantly associated with pre-diabetes in separate adjusted logistic regressions. When these 2 compounds were tested together only heptachlor epoxide remained significantly associated with pre-diabetes. The evidence supporting the relationship between pesticides and pesticide metabolites, with diabetes, was strongest for heptachlor epoxide and oxychlordane, intermediate for p,p′-DDT, and least for beta-hexachlorocyclohexane, p,p′-DDE, and trans-nonachlor. Mirex and dieldrin were not associated with total diabetes or pre-diabetes.     

The relationship between study sponsorship,risks of bias,and research outcomes in atrazine exposure studies conducted in non-human animals: Systematic review and meta-analysis

BackgroundA critical component of systematic review methodology is the assessment of the risks of bias of studies that are included in the review. There is controversy about whether funding source should be included in a risk of bias assessment of animal toxicology studies.ObjectiveTo determine whether industry research sponsorship is associated with methodological biases, the results, or conclusions of animal studies examining the effect of exposure to atrazine on reproductive or developmental outcomes.MethodsWe searched multiple electronic databases and the reference lists of relevant articles to identify original research studies examining the effect of any dose of atrazine exposure at any life stage on reproduction or development in non-human animals. We compared methodological risks of bias, the conclusions of the studies, the statistical significance of the findings, and the magnitude of effect estimates between industry sponsored and non-industry sponsored studies.ResultsFifty-one studies met the inclusion criteria. There were no differences in methodological risks of bias in industry versus non-industry sponsored studies. 39 studies tested environmentally relevant concentrations of atrazine (11 industry sponsored, 24 non-industry sponsored, 4 with no funding disclosures). Non-industry sponsored studies (12/24, 50.0%) were more likely to conclude that atrazine was harmful compared to industry sponsored studies (2/11, 18.1%) (p value = 0.07). A higher proportion of non-industry sponsored studies reported statistically significant harmful effects (8/24, 33.3%) compared to industry-sponsored studies (1/11; 9.1%) (p value = 0.13). The association of industry sponsorship with decreased effect sizes for harm outcomes was inconclusive.ConclusionOur findings support the inclusion of research sponsorship as a risk of bias criterion in tools used to assess risks of bias in animal studies for systematic reviews. The reporting of other empirically based risk of bias criteria for animal studies, such as blinded outcome assessment, randomization, and all animals included in analyses, needs to improve to facilitate the assessment of studies for systematic reviews.     

Pyrethroids in house dust from the homes of farm worker families in the MICASA study

Indoor pesticide exposure is a growing concern, particularly for pyrethroids, a commonly used class of pesticides. Pyrethroid concentrations may be especially high in homes of immigrant farm worker families, who often live in close proximity to agricultural fields and are faced with poor housing conditions, potentially causing high pest infestation and pesticide use. We investigate levels of pyrethroids in the house dust of farm worker family homes in a study of mothers and children living in Mendota, CA, within the population-based Mexican Immigration to California: Agricultural Safety and Acculturation (MICASA) Study. We present pesticide use data and levels of pyrethroid pesticides in indoor dust collected in 2009 as measured by questionnaires and a GC/MS analysis of the pyrethroids cis- and trans-permethrin, cypermethrin, deltamethrin, esfenvalerate and resmethrin in single dust samples collected from 55 households. Cis- and trans-permethrin had the highest detection frequencies at 67%, with median concentrations of 244 and 172 ng/g dust, respectively. Cypermethrin was detected in 52% of the homes and had a median concentration of 186 ng/g dust. Esfenvalerate, resmethrin and deltamethrin were detected in less than half the samples. We compared the pyrethroid concentrations found in our study to other studies looking at both rural and urban homes and daycares. Lower detection frequencies and/or lower median concentrations of cis- and trans-permethrin and cypermethrin were observed in our study as compared to those studies. However, deltamethrin, esfenvalerate and resmethrin were detected more frequently in the house dust from our study than in the other studies. Because households whose children had higher urinary pyrethroid metabolite levels were more likely to be analyzed in this study, a positive bias in our estimates of household pyrethroid levels may be expected. A positive association was observed with reported outdoor pesticide use and cypermethrin levels found in the indoor dust samples (r_s = 0.28, p = 0.0450). There was also a positive association seen with summed pyrethroid levels in house dust and the results of a pesticide inventory conducted by field staff (r_s = 0.32, p = 0.018), a potentially useful predictor of pesticide exposure in farm worker family homes. Further research is warranted to fully investigate the utility of such a measure.     

Urinary concentrations of organophosphate and carbamate pesticides in residents of a vegetarian community

Few population studies have measured urinary levels of pesticides in individuals with vegan, vegetarian, or organic diets. The objectives of this study were to evaluate whether a vegan/vegetarian diet was associated with increased exposure to organophosphate and carbamate pesticides, and to evaluate the impact of organic consumption on pesticide exposure in vegans and vegetarians. In the current pilot study conducted in 2013–2014, we collected spot urine samples and detailed 24 h recall dietary data in 42 adult residents of Amirim, a vegetarian community in Northern Israel. We measured urinary levels of non-specific organophosphate pesticide metabolites (dialkylphosphates, (DAPs)) and specific metabolites of the current-use pesticides chlorpyrifos (3,5,6-trichloro-2-pyridinol (TCPy)), propoxur (-isopropoxyphenol (IPPX)), and carbaryl (1-naphthol). Six DAP metabolites were detected in between 67 and 100% of urine samples, with highest geometric mean concentrations for dimethylphosphate (19.2 μg/g). Creatinine-adjusted median concentrations of total DAPs and of TCPy were significantly higher in Amirim residents compared to the general Jewish population in Israel (0.29 μmol/g compared to 0.16, p < 0.05 for DAPs and 4.32 μg/g compared to 2.34 μg/g, p < 0.05 for TCPy). Within Amirim residents, we observed a positive association between vegetable intake and urinary TCPy levels (rho = 0.47, p < 0.05) and lower median total dimethyl phosphate levels in individuals reporting that > 25% of the produce they consume is organic (0.065 μmol/L compared to 0.22, p < 0.05). Results from this pilot study indicate relatively high levels of urinary organophosphate pesticide metabolite concentrations in residents of a vegetarian community, a positive association between vegetable intake and urinary levels of a chlorpyrifos specific metabolite, and lower levels of total dimethyl phosphate in individuals reporting higher intake of organic produce. Results suggest that consumption of organic produce may offer some protection from increased exposure to organophosphate pesticide residues in vegetarians.     

The synergistic toxicity of the multiple chemical mixtures: Implications for risk assessment in the terrestrial environment

The combined toxicity of five insecticides (chlorpyrifos, avermectin, imidacloprid, λ-cyhalothrin, and phoxim), two herbicides (atrazine and butachlor) and a heavy metal (cadmium) has been examined with the earthworm acute toxicity test. Toxicological interactions of these chemicals in four, five, six, seven, and eight-component mixtures were studied using the combination-index (CI) equation method. In four-component and five-component mixtures, the synergistic effects predominated at lower effect levels, while the patterns of interactions found in six, seven, and eight-component mixtures displayed synergism. The λ-CY + IMI + BUT + ATR + CPF + PHO combination displayed the most strongly synergistic interaction, with CI values ranging from 0.09 to 0.15. The nature of the interaction changes with the effect level and the relevance of synergistic effects increase with the complexity of the mixture. The CI method was compared with the classical models of concentration addition (CA) and independent action (IA) and we found that the CI method could accurately predict the combined toxicity. The predicted synergism resulted from co-existence of the pesticides and the heavy metal especially at low effect levels may have important implications in risk assessment for the real terrestrial environment.     

A two reservoir model to predict Escherichia coli losses to water from pastures grazed by dairy cows

Animal agriculture has been identified as an important source of diffuse faecal microbial pollution of water. Our current understanding of the losses of faecal microbes from grazed pasture systems is however poor. To help synthesise our current knowledge, a simple two reservoir model was constructed to represent the faecal and environmental sources of Escherichia coli found in a grazed pastoral system. The size of the faecal reservoir was modelled on a daily basis with inputs from grazing animals, and losses due to die-off of E. coli and decomposition of the faecal material. Estimates were made of transport coefficients of E. coli losses from the two reservoirs. The concentration of E. coli measured in overland flow and artificial drainage from grazed plots, used for calibration of the model, showed a significant (P < 0.0001) decrease with days since last grazing — up to 120 days. Modelled E. coli runoff concentrations calibrated well with the regression line from the measured data up to 120 days. Variability of E. coli concentrations in the source faecal material could account for the variability in the measured runoff concentrations. Measured E. coli concentrations in artificial drainage water from 120 to 1300 days since last grazing appeared to be greater than the model predicted. The longer term data clearly illustrated the need for an environmental reservoir of E. coli in models of grazed pasture systems. Research is needed to understand the behaviour and impact of this environmental reservoir. Scenario analysis using the model indicated that rather than manipulating the faecal material itself post defecation, mitigation options should focus on manipulating grazing management.     

Pre- and postnatal exposures to pesticides and neurodevelopmental effects in children living in agricultural communities from South-Eastern Spain

BackgroundChildrens exposure to neurotoxic compounds poses a major problem to public health because of their actively developing brain that makes them highly vulnerable. However, limited information is available on neuropsychological effects in children associated with pre- and postnatal exposures to pesticides.ObjectiveTo evaluate the association between current and pre- and postnatal exposures to pesticides and their effects on neurodevelopment in children aged 6–11 years living in agricultural communities from South-Eastern Spain.MethodsAn ambispective study was conducted on 305 children aged 6–11 years randomly selected from public schools of the study area. Current exposure to organophosphate pesticides was assessed measuring children's urinary levels of dialkylphosphates (DAPs). Both prenatal and postnatal residential exposure to pesticides was estimated by developing a geographical information system (GIS) technology-based index that integrated distance-weighted measure of agricultural surface, time-series of crop areas per municipality and year, and land-use maps. Neuropsychological performance was evaluated with the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV). The association of pre- and postnatal and current pesticide exposure with WISC-IV scale scores was assessed using multivariate linear regression models and generalized estimating equation (GEE) models, respectively.ResultsGreater urinary DAP levels were associated with a poorer performance on intelligence quotient and verbal comprehension domain, with effects being more prominent in boys than in girls. The influence of an increase in 10 ha per year in crop surface around the child's residence during the postnatal period was associated with decreased intelligence quotient, processing speed and verbal comprehension scores. As regards prenatal exposure to pesticides, a poor processing speed performance was observed. These effects were also more prominent in boys than in girls.ConclusionsOur results suggest that postnatal exposure to pesticides can negatively affect children's neuropsychological performance. Prenatal exposure was weakly associated to neurodevelopment impairment.     

Human dietary intake of organohalogen contaminants at e-waste recycling sites in Eastern China

This study reports concentrations and human dietary intake of hexabromocyclododecanes (HBCDs), polychlorinated biphenyls (PCBs) as well as selected “novel” brominated flame retardants (NBFRs) and organochlorine pesticides, in ten staple food categories. Samples were sourced from areas in Taizhou City, eastern China, where rudimentary recycling and disposal of e-waste is commonplace, as well as from nearby non-e-waste impacted control areas. In most instances, concentrations in foods from e-waste recycling areas exceeded those from control locations. Concentrations of 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB) and bis-(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (BEH-TBP) in samples from e-waste sites were 3.09–62.2 ng/g and 0.81–16.3 ng/g lipid weight (lw), respectively; exceeding consistently those in foods acquired from control sites by an order of magnitude in many cases. In contrast, while concentrations of HBCD in some foods from e-waste impacted areas exceed those from control locations; concentrations in pork, shrimp, and duck liver are higher in control samples. This highlights the potential significance of non-e-waste sources of HBCD (e.g. building insulation foam) in our study areas. While concentrations of DDT in all foods examined except pork were higher in e-waste impacted samples than controls; our exposure estimates were well below the provisional tolerable daily intake of 0.01 mg/kg bw/day derived by the Joint FAO/WHO Meeting on Pesticide Residues. Concentrations of ΣPCBs resulted in exposures (650 and 2340 ng/kg bw/day for adults and children respectively) that exceed substantially the Minimal Risk Levels (MRLs) for ΣPCBs of 20 ng/kg bw/day derived by the Agency for Toxic Substances & Disease Registry. Moreover, when expressed in terms of dioxin-like toxicity equivalency based on the four dioxin-like PCBs monitored in this study (DL-PCBs) (PCB-105, 118, 156, and 167); concentrations in e-waste impacted foods exceed limits set by the European Union in 6 of the 8 food groups studied and result in dietary exposures for children (10.2 pg TEQ/kg bw/day) that exceed the WHO tolerable daily intake of 1–4 pg TEQ/kg bw/day.     

Priority and emerging flame retardants in rivers: Occurrence in water and sediment,Daphnia magna toxicity and risk assessment

The occurrence, partitioning and risk of eight polybrominated diphenyl ethers (PBDEs), nine new brominated (NBFRs) and ten organophosphorus flame retardants (OPFRs) were evaluated in three Spanish rivers suffering different anthropogenic pressures (Nalón, Arga and Besòs). OPFRs were ubiquitous contaminants in water (ΣOPFRs ranging from 0.0076 to 7.2 μg L^− 1) and sediments (ΣOPFRs ranging 3.8 to 824 μg kg^− 1). Brominated flame retardants were not detected in waters, whereas ΣPBDEs ranged from 88 to 812 μg kg^− 1 and decabromodiphenyl ethane (DBDPE) reached 435 μg kg^− 1 in sediments from the River Besòs, the most impacted river. The occurrence of flame retardants in river water and sediment was clearly associated with human activities, since the highest levels occurred near urban and industrial zones and after wastewater treatment plants discharge. Daphnia magna toxicity was carried out for OPFRs, the most ubiquitous flame retardants, considering individual compounds and mixtures. Toxicity of nine tested OPFRs differed largely among compounds, with EC₅₀ values ranging over three magnitude orders (0.31–381 mg L^− 1). Results evidenced that these compounds act by non-polar narcosis, since their toxicity was proportional to their lipophilicity (K_ow). Furthermore, their joint toxicity was additive, which means that single and joint toxicity can be predicted knowing their concentration levels in water using quantitative structure activity relationships (QSARs) and predictive mixture models. Based on these results, a risk assessment considering joint effect was performed calculating and summing risk quotients (RQs) for the water and sediment samples. No significant risk to D. magna (ΣRQs < 1) was observed for any of the monitored rivers.