Current-use Pesticides Research Articles

Ultrasound-assisted QuEChERS-based extraction using EDTA for determination of currently-used pesticides at trace levels in soil.

It is essential to monitor pesticides in soils as their presence at trace levels and their bioavailability can induce adverse effects on soil's ecosystems, animals, and human health. In this study, we developed an analytical method for the quantification of traces of multi-class pesticides in soil using liquid chromatography-tandem mass spectrometry. In this way, 31 pesticides were selected, including 12 herbicides, 9 insecticides, and 10 fungicides. Two extraction techniques were first evaluated, namely, the pressurized liquid extraction and the QuEChERS procedure. The latest one was finally selected and optimized, allowing extraction recoveries of 55 to 118%. The role of the chelating agent EDTA, which binds preferentially to soil cations that complex some pesticides, was highlighted. Coupled with liquid chromatography-tandem mass spectrometry, the procedure displayed very high sensitivity, with limits of quantification (LOQ) in the range 0.01-5.5ng/g. A good linearity (R2 > 0.992) was observed over two orders of magnitude (LOQ-100 [Formula: see text] LOQ) with good accuracy (80-120%) for all compounds except the two pyrethroids lambda-cyhalothrin and tau-fluvalinate (accuracy comprised between 50 and 175%) and the cyclohexanedione cycloxydim (accuracy < 35%). Good repeatability and reproducibility were also achieved. The method was finally successfully applied to 12 soil samples collected from 3 land-use types. Among the 31-targeted pesticides, 24 were detected at least once, with concentration levels varying from LOQ to 722ng/g. Many values were below 0.5ng/g, indicating that the developed method could provide new knowledge on the extremely low residual contents of some pesticides.

Quantifying exposure source allocation factors of pesticides in support of regulatory human health risk assessment

One of the challenges while assessing the aggregate exposure risk of pesticides is quantifying exposure doses from various exposure pathways. To address this issue, a regulatory screening approach is proposed for evaluating pesticide allocation factors (AFs) for major exposure pathways for rural and urban residents. This was achieved by integrating dynamiCrop and other screening models to estimate the potential human intake of residues from major crops at harvest, livestock products, and main environmental media (air, water, and soil). The AFs were calculated from the average daily dose factors (ADDFs) of pesticides via major exposure pathways, where a large AF of an exposure pathway indicates that a greater margin of exposure should be given to that exposure pathway. The simulated results for many current-use pesticides showed that the ingestion of crops had pesticide AFs close to 1.0, which indicated that the crop exposure pathway contributed to a significant portion of the total exposure to pesticides. In contrast, for legacy pesticides with high lipophilicity and low degradability in the environment, the simulated AFs for major environmental compartments (air, freshwater, and soil) accounted for relatively large exposures. As legacy pesticides have been banned globally, exposure pathways via the food web and environmental media cannot be neglected because of their high lipophilicity and environmental persistence. Although other factors such as geographical conditions and living habits should be considered to improve the spatial resolution of the model, the method proposed in this study can serve as a preliminary tool to conduct screening-level risk assessments for populations by considering the allocated exposure to pesticides via major exposure pathways.

Fate and ecological risks of current-use pesticides in seawater and sediment of the Yellow Sea and East China Sea

With the frequent use of chemical pesticides, the current-use pesticides (CUPs) emerge and concentrate in the sea. The partition between the sediment and seawater is essential for understanding the environmental fate of CUPs. However, there is little research on this topic. In the present study, seventeen CUPs were screened in seawater and sediment samples collected from the Yellow Sea and East China Sea. Total concentration of 17 CUPs in surface seawater samples ranged from 9.5 to 267.3 ng/L, with 6 CUPs presenting 100% detection frequency. Carbendazim, tricyclazole, tebuconazole, atrazine and imidacloprid accounted for >80% of all CUPs, which was due to their large application in the local agriculture and fishing activities. Higher concentration sites were located near the shore and Yangtze river estuary, indicating intense human activities and riverine input that elevated the level of CUPs in marginal sea. The pesticides in seawater were mainly found in the surface followed by the bottom layer, which indicated that atmospheric deposition and re-suspension played key roles for their vertical distribution characteristics. The high fugacity fraction ratios (ff > 0.5) indicated the non-equilibrium state of pesticides that might have been transferred from sediment to seawater at most sites. These 17 detectable pesticides in seawater were at low levels, presenting ignorable or low toxic effects to aquatic organisms.

Simultaneous GC-NCI-MS Determination of Persistent Organic Pollutants and Current-Use Pesticides in Breast Milk Samples

To preserve human health, persistent organic pollutants (POPs) and current-use pesticides (CUPs) should be monitored in fatty tissues, including breast milk. Therefore, this study aimed to optimize sample preparation conditions using a 32 factorial design for the determination of POPs and CUPs by gas chromatography coupled to mass spectrometry with negative chemical ionization (GC-NCI-MS). The method was validated for 57 POP and CUP compounds using hexane:acetone for extraction and clean-up by dispersive solid phase extraction (d-SPE) with Florisil®. The matrix effect was compensated by extracted analytical calibration. Method validation showed satisfactory results with limits of detection of 3 to 13 ng g-1 of fat. The method presented adequate accuracy (recoveries from 72 to 117%) and precision (relative standard deviation (RSD) ≤ 18%) and was applied to breast milk samples from Rio Grande do Sul State, southern Brazil, wherein all samples contained at least one compound. With principal component analysis, it was possible to associate the pesticides detected with the city of origin of the samples and the number of pregnancies of nursing mothers. Additionally, the analytical method was effective for the determination of trace levels of POPs and CUPs in breast milk and can be applied in biomonitoring studies.

First insights into the occurrence of pesticide residues in edible insects from sub-Saharan African countries

Pesticide use is a common practice worldwide, especially in Sub-Saharan African (SSA) countries, where ongoing agriculture intensification and the need for disease vector control make it essential. The population can thus be exposed to variable amounts of pesticides through the diet. Edible insects are a highly regarded food source in SSA. However, they are still mostly harvested from the wild, where chemical applications are not necessarily controlled, representing a major cause of concern for consumers. We investigated residues of legacy (OCPs) and current-use pesticides (CUPs) in selected edible insects commonly consumed in Uganda and Nigeria, and evaluated the eventual health risk for the adult population associated with their consumption. Targeted OCPs were &lt; LOQ in all analysed edible insects, except for hexachlorobenzene (up to 0.87 ng/g dw), while several CUPs were present at notable levels. Cypermethrin showed the highest median concentration (17 ng/g dw), while the Nigerian cricket Brachytrupes membranaceus was the most contaminated sample, with concentrations of aldicarb, propoxur, chlorpyrifos, dichlorvos and paclobutrazol reaching 118 ng/g dw, 327 ng/g dw, 156 ng/g dw, 26 ng/dw, and 14 ng/g dw, respectively. The concentrations of pesticides were generally well below the available maximum residue levels (MRLs), and the dietary risk assessment did not indicate health threats for the adult population. However, we suggest that the monitoring of the chemical safety of edible insects in SSA should be further investigated and insects should be integrated into more extensive dietary studies.

Pesticide Research on Environmental and Human Exposure and Risks in Sub-Saharan Africa: A Systematic Literature Review.

On the African continent, ongoing agriculture intensification is accompanied by the increasing use of pesticides, associated with environmental and public health concerns. Using a systematic literature review, we aimed to map current geographical research hotspots and gaps around environmental and public health risks research of agriculture pesticides in Sub-Saharan Africa (SSA). Studies were included that collected primary data on past and current-used agricultural pesticides and assessed their environmental occurrence, related knowledge, attitude and practice, human exposure, and environmental or public health risks between 2006 and 2021. We identified 391 articles covering 469 study sites in 37 countries in SSA. Five geographical research hotspots were identified: two in South Africa, two in East Africa, and one in West Africa. Despite its ban for agricultural use, organochlorine was the most studied pesticide group (60%; 86% of studies included DDT). Current-used pesticides in agriculture were studied in 54% of the study sites (including insecticides (92%), herbicides (44%), and fungicides (35%)). Environmental samples were collected in 67% of the studies (e.g., water, aquatic species, sediment, agricultural produce, and air). In 38% of the studies, human subjects were investigated. Only few studies had a longitudinal design or assessed pesticide’s environmental risks; human biomarkers; dose-response in human subjects, including children and women; and interventions to reduce pesticide exposure. We established a research database that can help stakeholders to address research gaps, foster research collaboration between environmental and health dimensions, and work towards sustainable and safe agriculture systems in SSA.

Forests effects on the environmental fates of organic pollutants in a tropical watershed

Poly-brominated diphenyl ethers (PBDEs), dioxins, furans and current-use pesticides (CUPs) are common organic pollutants that have received global scrutiny due to their association with adverse environmental and health impacts. However, there is limited previous work assessing their environmental fates in the context of tropical multi-use watersheds. The aim of this study was to estimate the effect of forests on long-term environmental fate for some PBDEs, dioxins, furans and CUPs for a case study watershed of a tropical developing country (the Rio Cobre River drainage basin, Jamaica). Specifically, a dynamic, 16-compartment environmental multimedia model, RioShed, was developed and applied to calculate compartmental concentrations, as well as some long-term environmental fate metrics. Results indicate that the presence of tropical forests, especially those that are evergreen, reduced the atmospheric concentrations, atmospheric long-range transport potential, and the overall persistence of the study pollutants. Reductions in atmospheric concentrations by tropical forests were most enhanced for the more polar CUPs. Forest parameters that notably influenced soil concentration and/or overall persistence included the canopy drip parameter, the leaf area index and the wax erosion rate. The results of this research are expected to inform land-use and environmental management of the study area and similar tropical regions.

Quantitative assessment of multiple pesticides in silicone wristbands of children/guardian pairs living in agricultural areas in South Africa

Little is known about personal and time-integrated exposure to past and current used pesticides in agricultural areas and within-family exposure similarities. We aimed to assess exposure to pesticides using silicone wristbands in child/guardian pairs living on farms and in villages within two agricultural areas in South Africa.Using silicone wristbands, we quantified 21 pesticides in child/guardian pairs in 38 households over six days in 2018. Levels (in ng/g wristband) of pesticides and their transformation products (12 current-use pesticides and nine organochlorine pesticides) were measured using GC–MS/MS. We assessed the correlation between pesticide levels and between household members using Spearman correlation coefficients (rs). Multivariable generalized least squares (GLS) models, using household id as intercept, were used to determine level of agreement between household members, exposure differences between children and guardians and exposure predictors (study area, household location [farm vs. village] and household pesticide use).We detected 16 pesticides with highest detection frequencies for deltamethrin (89%), chlorpyrifos (78%), boscalid (56%), cypermethrin (55%), and p,p′-DDT (48%). Most wristbands (92%) contained two or more pesticides (median seven (range one to 12)). Children had higher concentrations than guardians for four pesticides. Correlation between the pesticide levels were in most cases moderate (rs 0.30–0.68) and stronger in children than in guardians. Five pesticides showed moderate to strong correlation between household members, with the strongest correlation for boscalid (rs 0.84). Exposure differences between the two agricultural areas were observed for chlorpyrifos, diazinon, prothiofos, cypermethrin, boscalid, p,p′-DDT and p,p′-DDE and within areas for cypermethrin.We showed that for several pesticides children had higher exposure levels than guardians. The positive correlations observed for child/guardian pairs living in the same household suggest non-occupational shared exposure pathways in these communities.

Seasonal variations in air concentrations of 27 organochlorine pesticides (OCPs) and 25 current-use pesticides (CUPs) across three agricultural areas of South Africa

For decades pesticides have been used in agriculture, however, the occurrence of legacy organochlorine pesticides (OCPs) and current-use pesticides (CUPs) is poorly understood in Africa. This study investigates air concentrations of OCPs and CUPs in three South African agricultural areas, their spatial/seasonal variations and mixture profiles.Between 2017 and 2018, 54 polyurethane foam-disks passive air-samplers (PUF-PAS) were positioned in three agricultural areas of the Western Cape, producing mainly apples, table grapes and wheat. Within areas, 25 CUPs were measured at two sites (farm and village), and 27 OCPs at one site (farm). Kruskal-Wallis tests investigated area differences in OCPs concentrations, and linear mixed-effect models studied differences in CUPs concentrations between areas, sites and sampling rounds.In total, 20 OCPs and 16 CUPs were detected. A median of 16 OCPs and 10 CUPs were detected per sample, making a total of 11 OCPs and 24 CUPs combinations. Eight OCPs (trans-chlordane, o,p’-/p,p’-dichlorodiphenyldichloroethylene (DDE)/dichlorodiphenyltrichloroethane (DDT), endosulfan sulfate, γ-hexachlorocyclohexane and mirex) and two CUPs (carbaryl and chlorpyrifos) were quantified in all samples. p,p’-DDE (median 0.14 ng/m3) and chlorpyrifos (median 0.70 ng/m3) showed the highest concentrations throughout the study. Several OCPs and CUPs showed different concentrations between areas and seasons, although CUPs concentrations did not differ between sites. OCPs ratios suggest ongoing chlordane use in the region, while DDT and endosulfan contamination result from past-use.Our study revealed spatial and seasonal variations of different OCPs and CUPs combinations detected in air. Further studies are needed to investigate the potential cumulative or synergistic risks of the detected pesticides.

Target and Suspect Screening of Urinary Biomarkers for Current-use Pesticides: Application of a Simple Extraction Method.

Pesticide residues pose a great threat to human health. Biomonitoring with urine samples has often been used to assess pesticide exposure to humans, and identifying appropriate biomarkers is a premise of success. Current-use pesticides (CUPs) including neonicotinoids tend to be transformed in an organism, and thus the biomonitoring studies focusing on parent compounds alone may underestimate their risk. It is imperative to develop effective methods to analyze CUPs and their metabolites simultaneously and to identify viable metabolites as urinary biomarkers. For analyzing xenobiotics in urine, we optimized CH3 COCH3 -MgSO4 extraction coupled with a high-performance liquid chromatography-tandem mass spectrometry detection method. The method had sensitive method detection limits (0.11-1.39 ng/ml), low matrix effects, and satisfactory recovery and precision (49.4% ± 7.2%-99.8% ± 17.8%) for neonicotinoids and their metabolites. Application of the method for real samples showed that children living in rural areas in South China were ubiquitously exposed to CUPs, including neonicotinoids, fipronil, and chlorpyrifos, and urinary residues were mainly in the form of metabolites. Suitable biomarkers were identified for individual neonicotinoids, including imidacloprid-olefin and imidacloprid-guanidine for imidacloprid, acetamiprid-N-desmethyl for acetamiprid, thiacloprid-amide for thiacloprid, and N-desmethyl-thiamethoxam and thiamethoxam for thiamethoxam. Three metabolites were mainly reported in urine samples, including imidacloprid-urea, thiacloprid-amide, and N-desmethyl-thiamethoxam. In addition, the method was also applied for suspect screening, and an additional metabolite (clothianidin-desmethyl-nitrosoguanidine) was identified, showing its potential application in suspect analysis. Environ Toxicol Chem 2022;41:73-80. © 2021 SETAC.

Concentration of current-use pesticides in frogs from the Pampa region and correlation of a mixture toxicity index with biological effects

Contamination with current-use pesticides is frequently mentioned as a key factor in global amphibian declines although a limited number of studies have examined the mixture of pesticides accumulated by free-living frogs. This study examined the presence of 46 different pesticide residues in the muscle and kidney tissues of two frog species living in close association with row crops in the Pampa region of Argentina: The terrestrial Leptodactylus latinasus and the semi-aquatic Leptodactylus latrans. A total of 20 different pesticides were identified in frog tissues; chlorpyrifos-methyl, pirimiphos-methyl and acetochlor being the most frequently detected molecules. Overall, one or more pesticide residues (up to 12 in a single frog) were detected in 40–57 % of L. latrans. L. latinasus was found to present more pesticide detections than L. latrans. Interestingly, frog sampled in a natural reserve where no pesticides are applied presented an equivalent frequency of detections as frogs living near a crop. In L. latrans, the calculation of a pesticide toxicity index (PTI) permitted to highlight the existence of a strong positive correlation between PTI and liver GSH contents of females whereas, in males, PTI was negatively correlated with the perimeter of testicular seminiferous tubules. Males also presented near significant negative correlations between PTI and both body condition and the scaled fat index. These results indicate that frogs inhabiting agricultural regions are exposed to a complex and diffuse contamination by pesticide mixtures which is likely responsible for a number of biological effects that may be relevant at the population level.

Measuring current-use pesticides in air: A comparison of silicon carbide foam to XAD as passive air samplers

Silicon carbide foams have recently proved its efficiency as newly introduced passive sampler for air monitoring. The aim of this work is to assess the field potential of the SiC foams in comparison to the well-known XAD®-2 resins and to improve its performance by grafting Nitrogen-doped carbon (N-C) and Nitrogen-doped carbon nanotubes (N-CNT) at several temperatures. The results generated by this work showed that grafted SiC foams are prone to be highly competitive with commonly used XAD®-2 resins and gave better results than the regular SiC foams. Moreover, the obtained results showed that among others both 450 °C N-C SiC and 900 °C N-CNT SiC allowed detection of the highest amount of pesticides and could be considered as new potential adsorbent for pesticides in air.

Exposure to common-use pesticides, manganese, lead, and thyroid function among pregnant women from the Infants' Environmental Health (ISA) study, Costa Rica

BackgroundPesticides and metals may disrupt thyroid function, which is key to fetal brain development. ObjectivesTo evaluate if current-use pesticide exposures, lead and excess manganese alter free thyroxine (FT4), free triiodothyronine (FT3), and thyroid stimulating hormone (TSH) concentrations in pregnant women from the Infants' Environmental Health Study (ISA). MethodsAt enrollment, we determined women's (n = 400) specific-gravity corrected urinary pesticide (μg/L) metabolite concentrations of mancozeb (ethylene thiourea (ETU)), pyrimethanil, thiabendazole, chlorpyrifos, synthetic pyrethroids, and 2,4-D. We also measured manganese hair (MnH) (μg/g) and blood (MnB) (μg/L), and blood lead (PbB) (μg/L) concentrations. To detect an immediate and late effect on thyroid homeostasis, we determined TSH, FT4 and FT3 in serum obtained at the same visit (n = 400), and about ten weeks afterwards (n = 245). We assessed associations between exposures and outcomes with linear regression and general additive models, Bayesian multivariate linear regression, and Bayesian kernel machine regression. ResultsAbout 80%, 94%, and 100% of the women had TSH, FT4, and FT3 within clinical reference ranges, respectively. Women with higher urinary ETU, and pyrimethanil-metabolites, had lower FT4: β = −0.79 (95%CI = −1.51, −0.08) and β = −0.29 (95%CI = −0.62, −0.03), respectively, for each tenfold increase in exposure. MnB was positively associated with FT4 (β = 0.04 (95%CI = 0.00, 0.07 per 1 μg/L increase), and women with high urinary pyrethroid-metabolite concentrations had decreased TSH (non-linear effects). For the late-effect analysis, metabolites of pyrethroids and chlorpyrifos, as well as MnH, and PbB were associated decreased TSH, or increased FT4 and/or FT3. DiscussionMancozeb (ETU) and pyrimethanil may inhibit FT4 secretion (hypothyroidism-like effect), while chlorpyrifos, pyrethroids, MnB, MnH, PbB and Mn showed hyperthyroidism-like effects. Some effects on thyroid homeostasis seemed to be immediate (mancozeb (ETU), pyrimethanil, MnB), others delayed (chlorpyrifos, MnH, PbB), or both (pyrethroids), possibly reflecting different mechanisms of action.

Point or non-point source: Toxicity evaluation using m-POCIS and zebrafish embryos in municipal sewage treatment plants and urban waterways

Municipal sewage treatment plants (STPs) have been regarded as an important source of organic contaminants in aquatic environment. To assess the impact of STPs on occurrence and toxicity of STP-associated contaminants in receiving waterways, a novel passive sampler modified from polar organic chemical integrative sampler (m-POCIS) was deployed at the inlet and outlet of a STP and several upstream and downstream sites along a river receiving STP effluent in Guangzhou, China. Eighty-seven contaminants were analyzed in m-POCIS extracts, along with toxicity evaluation using zebrafish embryos. Polycyclic musks were the predominant contaminants in both STP and urban waterways, and antibiotics and current-use pesticides (e.g., neonicotinoids, fiproles) were also ubiquitous. The m-POCIS extracts from downstream sites caused significant deformity in embryos, yet the toxicity could not be explained by the measured contaminants, implying the presence of nontarget stressors. Sewage treatment process substantially reduced embryo deformity, chemical oxygen demand, and contamination levels of some contaminants; however, concentrations of neonicotinoids and fiproles increased after STP treatment, possibly due to the release of chemicals from perturbed sludge. Source identification showed that most of the contaminants found in urban waterways were originated from nonpoint runoff, while cosmetics factories and hospitals were likely point sources for musks and antibiotics, respectively. Although the observed embryo toxicity could not be well explained by target contaminants, the present study showed a promising future of using passive samplers to evaluate chemical occurrence and aquatic toxicity concurrently. Zebrafish embryo toxicity significantly decreased after sewage treatment, but higher toxicity was observed for downstream samples, demonstrating that urban runoff may produce detrimental effects to aquatic life, particularly in rainy season. These results highlight the relevance of monitoring nonpoint source pollution along with boosting municipal sewage treatment infrastructure.

Current use pesticides in soil and air from two agricultural sites in South Africa: Implications for environmental fate and human exposure

Concerns about the possible negative impacts of current use pesticides (CUPs) for both the environment and human health have increased worldwide. However, the knowledge on the occurrence of CUPs in soil and air and the related human exposure in Africa is limited. This study investigated the presence of 30 CUPs in soil and air at two distinct agricultural sites in South Africa and estimated the human exposure and related risks to rural residents via soil ingestion and inhalation (using hazard quotients, hazard index and relative potency factors). We collected 12 soil and 14 air samples over seven days during the main pesticide application season in 2018. All samples were extracted, purified and analyzed by high-performance liquid chromatography coupled with tandem mass spectrometry. In soils, nine CUPs were found, with chlorpyrifos, carbaryl and tebuconazole having the highest concentrations (up to 63.6, 1.10 and 0.212 ng g−1, respectively). In air, 16 CUPs were found, with carbaryl, tebuconazole and terbuthylazine having the highest levels (up to 25.0, 22.2 and 1.94 pg m−3, respectively). Spatial differences were observed between the two sites for seven CUPs in air and two in soils. A large dominance towards the particulate phase was found for almost all CUPs, which could be related to mass transport kinetics limitations (non-equilibrium) following pesticide application. The estimated daily intake via soil ingestion and inhalation of individual pesticides ranged from 0.126 fg kg−1 day−1 (isoproturon) to 14.7 ng kg−1 day−1 (chlorpyrifos). Except for chlorpyrifos, soil ingestion generally represented a minor exposure pathway compared to inhalation (i.e. <5%). The pesticide environmental exposure largely differed between the residents of the two distinct agricultural sites in terms of levels and composition. The estimated human health risks due to soil ingestion and inhalation of pesticides were negligible although future studies should explore other relevant pathways.

Global intercomparison of polyurethane foam passive air samplers evaluating sources of variability in SVOC measurements

Polyurethane foam passive air samplers (PUF-PAS) are the most common type of passive air sampler used for a range of semi-volatile organic compounds (SVOCs), including regulated persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), and emerging contaminants (e.g., novel flame retardants, phthalates, current-use pesticides). Data from PUF-PAS are key indicators of effectiveness of global regulatory actions on SVOCs, such as the Global Monitoring Plan of the Stockholm Convention on Persistent Organic Pollutants. While most PUF-PAS use similar double-dome metal shielding, there is no standardized dome size, shape, or deployment configuration, with many different PUF-PAS designs used in regional and global monitoring. Yet, no information is available on the comparability of data from studies using different PUF-PAS designs. We brought together 12 types of PUF-PAS used by different research groups around the world and deployed them in a multi-part intercomparison to evaluate the variability in reported concentrations introduced by different elements of PAS monitoring. PUF-PAS were deployed for 3 months in outdoor air in Kjeller, Norway in 2015–2016 in three phases to capture (1) the influence of sampler design on data comparability, (2) the influence of analytical variability when samplers are analyzed at different laboratories, and (3) the overall variability in global monitoring data introduced by differences in sampler configurations and analytical methods. Results indicate that while differences in sampler design (in particular, the spacing between the upper and lower sampler bowls) account for up to 50 % differences in masses collected by samplers, the variability introduced by analysis in different laboratories far exceeds this amount, resulting in differences spanning orders of magnitude for POPs and PAHs. The high level of variability due to analysis in different laboratories indicates that current SVOC air sampling data (i.e., not just for PUF-PAS but likely also for active air sampling) are not directly comparable between laboratories/monitoring programs. To support on-going efforts to mobilize more SVOC data to contribute to effectiveness evaluation, intercalibration exercises to account for uncertainties in air sampling, repeated at regular intervals, must be established to ensure analytical comparability and avoid biases in global-scale assessments of SVOCs in air caused by differences in laboratory performance.

Environmental pesticide concentrations in air and pregnant women’s urinary pesticide metabolites in the Infants’ Environmental Health Study (ISA)

BACKGROUND AND AIM: We evaluated associations between environmental pesticide concentrations in air and specific urinary pesticide metabolites among pregnant women from the Infants' Environmental Health Study (ISA) in Matina County, Costa Rica. METHODS: We used a Bayesian spatiotemporal model to extrapolate concentrations of the fungicide pyrimethanil and the insecticide chlorpyrifos measured with polyurethane foam passive air samplers (n=48, from 12 schools) across space and time. Using mixed models, we compared them with urinary specific-gravity corrected pesticide metabolite concentrations: 4-hydroxypyrimethanil (OHP, metabolite of pyrimethanil) and 3,5,6-trichloro-2-pyridinol (TCPy, metabolite of chlorpyrifos), repeatedly obtained among 451 pregnant women from the ISA Study (n=951). Pyrimethanil in air, OHP, and TCPy were log-transformed prior to statistical analysis to normalize residuals of models. We considered several covariables. RESULTS:Median (p10-p90) concentrations were: pyrimethanil = 1.33 (0.27-17.0) ng/m3, chlorpyrifos = 15.62 (4.38 - 24.19) ng/m3, OHP = 0.39 (0.06- 2.75) ug/L, and TCPy = 1.63 (0.75-4.27) µg/L. A 10% increase in pyrimethanil in air was associated with a 5.7% (95% CI 4.6, 6.8) increase in urinary OHP (μg/L), women who lived near banana plantations had higher OHP, whilst frequent consumption of rice and beans was associated with lower OHP. In addition, each 1 ng/m3 increase in chlorpyrifos in air was associated with a 1.5% increase in TCPy (μg/L), and women who worked in agriculture tended to have higher TCPy. CONCLUSIONS:Despite the limitations of having limited data on pesticide air concentrations in space and time, and biomonitoring of pesticides with short half-lives, the results of this study indicate environmental air concentrations of pyrimethanil and chlorpyrifos explained to some extent internal pesticide metabolite concentrations in pregnant women. Our results suggest that inhalation of these pesticides is one of the pathways of environmental exposure. Passive air sampling of current-use pesticides seems a promising method to monitor environmental pesticide exposure. KEYWORDS: passive air sampling, pesticides, environmental exposure, biomonitoring

Pollution levels and biomarker responses in zooplankton from three hydrographic regions of southern Brazil: An integrated approach for water quality monitoring

Levels of chemical pollutants [organochlorine pesticides (OCs), current-use pesticides (CUPs), polycyclic aromatic hydrocarbons (PAHs) and trace-metals (Cu, Pb, Zn and Cd)], and biomarkers [metallothioneins (MTs) and lipid peroxidation (LPO)] were assessed in zooplankton of four watersheds belonging to three different hydrographic regions in southern Brazil. Results show that bioaccumulation followed a geographical pattern, as zooplankton from more coastal areas were the less affected. Elevated levels of CUPs (3257–6360 ng/g) and DDTs (1648–3258 ng/g) were found in zooplankton collected in sampling sites located in agricultural areas. In turn, elevated levels of HCHs (419–488 ng/g), endosulfans (108–215 ng/g) and PAHs (82,408–151,400 ng/g) were found in zooplankton collected in areas characterized by agricultural and industrial activities. Importantly, already banned pesticides were also detected, thus raising concerns. Regarding biomarkers, MTs and LPO levels were positively related with pollutant concentration in zooplankton from all assessed areas. This finding points out the suitability of both MTs and LPO as biological tools for environmental monitoring programs. Also, it is important to note that zooplankton is a major component of the first lfevel of consumers in aquatic system food chains. Therefore, chemical pollutants accumulated in zooplankton are likely to be biomagnified along the higher levels of the food chain, thus raising great concern. Therefore, the present study indicates MTs and LPO as suitable tools to predict ecological impacts in aquatic systems, using zooplankton was biomonitor species.

Spatio-temporal variation of outdoor and indoor pesticide air concentrations in homes near agricultural fields

BackgroundPrevious research has shown that many current-use pesticides can be detected in air around application areas. Environmental exposure to pesticides may cause adverse health effects, necessitating accurate assessment of outdoor and indoor air concentrations for people living close to spraying sites. We evaluated outdoor and indoor air concentrations of different pesticides, as well as factors influencing spatial and temporal variations. MethodsWe collected outdoor air samples at 58 homes located within 250 m of bulb fields and 15 control homes located further than 500 m from any agricultural field. Outdoor air sampling following a pesticide spray event was performed 24-h a day for 7 consecutive days. Two full day samples were collected at the same locations during a non-use period. In homes located within 50 m from agricultural fields (N = 18), indoor air was also sampled for the first 24 h after field spraying. Samples were analysed for a total of 46 pesticides and degradation products. From these, 11 were actively used on nearby fields, 3 were used in bulb disinfection and 6 were degradation products. ResultsCompared to non-use periods, pesticides concentrations were 5–10 times higher in outdoor air during application periods. Similar concentration differences were observed between exposed homes and controls both during pesticide use and non-use period. For 14 pesticides, there were moderate correlations (spearman > 0.4–0.7) between outdoor and indoor air concentrations. Wind direction, evapotranspiration and agricultural area surrounding a home were the most important determinants of air concentration of the applied pesticides. ConclusionsThis study provides strong evidence suggesting that environmental exposure to pesticides via air is not limited to the day of application and may occur year-round. The concentrations appeared higher during the use period. Factors influencing the local fate of pesticides in air may differ significantly between compounds.

Identifying Chemicals and Mixtures of Potential Biological Concern Detected in Passive Samplers from Great Lakes Tributaries Using High-Throughput Data and Biological Pathways.

Waterborne contaminants were monitored in 69 tributaries of the Laurentian Great Lakes in 2010 and 2014 using semipermeable membrane devices (SPMDs) and polar organic chemical integrative samplers (POCIS). A risk‐based screening approach was used to prioritize chemicals and chemical mixtures, identify sites at greatest risk for biological impacts, and identify potential hazards to monitor at those sites. Analyses included 185 chemicals (143 detected) including polycyclic aromatic hydrocarbons (PAHs), legacy and current‐use pesticides, fire retardants, pharmaceuticals, and fragrances. Hazard quotients were calculated by dividing detected concentrations by biological effect concentrations reported in the ECOTOX Knowledgebase (toxicity quotients) or ToxCast database (exposure–activity ratios [EARs]). Mixture effects were estimated by summation of EAR values for chemicals that influence ToxCast assays with common gene targets. Nineteen chemicals—atrazine, N,N‐diethyltoluamide, di(2‐ethylhexyl)phthalate, dl‐menthol, galaxolide, p‐tert‐octylphenol, 3 organochlorine pesticides, 3 PAHs, 4 pharmaceuticals, and 3 phosphate flame retardants—had toxicity quotients >0.1 or EARs for individual chemicals >10–3 at 10% or more of the sites monitored. An additional 4 chemicals (tributyl phosphate, triethyl citrate, benz[a]anthracene, and benzo[b]fluoranthene) were present in mixtures with EARs >10–3. To evaluate potential apical effects and biological endpoints to monitor in exposed wildlife, in vitro bioactivity data were compared to adverse outcome pathway gene ontology information. Endpoints and effects associated with endocrine disruption, alterations in xenobiotic metabolism, and potentially neuronal development would be relevant to monitor at the priority sites. The EAR threshold exceedance for many chemical classes was correlated with urban land cover and wastewater effluent influence, whereas herbicides and fire retardants were also correlated to agricultural land cover. Environ Toxicol Chem 2021;40:2165–2182. Published 2021. This article is a U.S. Government work and is in the public domain in the USA. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.