Diet and food type affect urinary pesticide residue excretion profiles in healthy individuals: results of a randomized controlled dietary intervention trial.

BACKGROUND: Observational studies have linked pesticide exposure to various diseases, whereas organic food consumption has been associated with positive health outcomes. Organic farming standards prohibit the use of most pesticides, and organic food consumption may therefore reduce pesticide exposure. OBJECTIVES: To determine the effects of diet (Western compared with Mediterranean) and food type (conventional compared with organic) and sex on urinary pesticide residue excretion (UPRE), as well as associations between specific diet components and UPRE. METHODS: In this 2-wk, randomized dietary intervention trial, healthy adults were randomly allocated to an intervention (n = 13) or conventional (n = 14) group. Whereas participants in the intervention group consumed a Mediterranean diet (MedDiet) made entirely from organic foods, the conventional group consumed a MedDiet made entirely from conventional foods. Both groups consumed habitual Western diets made from conventional foods before and after the 2-wk intervention period. The primary outcome was UPRE. In addition, we assessed diet composition and pesticide residue profiles in foods eaten. Participants were aware of group assignment, but the study assessors were not. RESULTS: During the intervention period, total UPRE was 91% lower with organic (mean 17 µg/d; 95% CI: 15, 19) than with conventional (mean 180 µg/d; 95% CI: 153, 208) food consumption (P < 0.0001). In the conventional group, switching from the habitual Western diet to the MedDiet increased insecticide excretion from 7 to 25 µg/d (P < 0.0001), organophosphate excretion from 5 to 19 µg/d (P < 0.0001), and pyrethroid residue excretion from 2.0 to 4.5 µg/d (P < 0.0001). Small but significant effects of sex were detected for chlormequat, herbicide, and total pesticide residue excretion. CONCLUSIONS: Changing from a habitual Western diet to a MedDiet was associated with increased insecticide, organophosphate, and pyrethroid exposure, whereas organic food consumption reduced exposure to all groups of synthetic chemical pesticides. This may explain the positive health outcomes linked to organic food consumption in observational studies. This trial was registered at www.clinicaltrials.gov as NCT03254537.

Pesticides and their metabolites in human urine: development of multi-analyte method by LC-MS/MS and GC-MS/MS.

The objective of this study consists of being able to develop a precise, reliable, easy, cheap and quick method to identify and quantify the presence of pesticide metabolites and their parents in human urine. In order to reach our purpose we selected the pesticides and their metabolites with intended uses on permanent crops such as orchards and vineyard. The activity planning started with the identification of the target list carried out by UHPLC-MS/MS and GC-MS/MS, succeeded by several tests oriented to determine the best sample treatment having recourse to instrumental analysis in the range 5-100 ng/mL. Several purifications were also investigated combining different adsorbents (PSA, EMR-lipid and final polish pouch). The use of formic acid during the extraction step has no impact on the recoveries, whereas the PSA adsorbent in the cleanup step negatively affects the results for all investigated metabolites. Any substantial differences were not observed in urine matrix for parent compounds achieving recoveries higher than 80% and RSD less than 20%. The final polish in combination or not with Enhanced Matrix Removal EMR-lipid did not show statistically significant difference in term of trueness and precision for both metabolites and parents, as evaluated by one-way ANOVA. The 3-OH THPI was the most critical compound with not acceptable results for linearity, trueness and precision.

Modified QuEChERS extraction method followed by simultaneous quantitation of nine multi-class pesticides in human blood and urine by using GC-MS.

Organophosphate, carbamate and pyrethroid pesticides are the most common insecticides used worldwide. They may cause chronic poisoning in farmers and acute poisoning in homicidal or suicidal cases. The determination of trace levels of these pesticides in human blood and urine is very challenging. This study focuses on a simultaneous quantitation method that was developed and validated for multi-class nine pesticides belonging to organophosphate, carbamate and pyrethroid classes in human blood and urine. Target pesticides were extracted from blood and urine using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction method. Capillary column DB-35 ms (15 m × 0.25 mm, 0.25 µm) was used for chromatography with a 0.079 ml/min flow rate of carrier gas at constant pressure mode. Quantitation of sulfotep, phorate, carbofuran, chlorpyriphos, profenophos, triazophos, pyriproxyfen, lambda-cyhalothrin and permethrin was performed by mass spectrometer equipped with electron impact ionization source using selected ion monitoring (SIM) mode. The lower and upper limits of quantitation for all nine pesticides were 0.01 mg/L and 2.0 mg/dL respectively. The proposed method was proved to be simple, fast, sensitive, and robust. It has been applied to the analysis of 9 pesticides samples.

Urine glyphosate level as a quantitative biomarker of oral exposure.

BACKGROUND: Since the classification of glyphosate as a Group 2A substance "probably carcinogenic to humans" by the IARC in 2015, human health concerns have been raised regarding the exposure of operators, bystanders, and consumers. Urine measurement studies have been conducted, but since toxicokinetic data on glyphosate in humans is lacking, a meaningful interpretation of this data regarding exposure is not possible. OBJECTIVE: This study aims to determine the fraction of glyphosate and AMPA excretion in urine after consuming ordinary food with glyphosate residue, to estimate dietary glyphosate intake. METHODS: Twelve participants consumed a test meal with a known amount of glyphosate residue and a small amount of AMPA. Urinary excretion was examined for the next 48 h. RESULTS: Only 1% of the glyphosate dose was excreted in urine. The urinary data indicated the elimination half-life was 9 h. For AMPA, 23% of the dose was excreted in urine, assuming that no metabolism of glyphosate to AMPA occurred. If all of the excreted AMPA was a glyphosate metabolite, this corresponds to 0.3% of the glyphosate dose on a molar basis. CONCLUSION: This study provides a basis for estimating oral glyphosate intake using urinary biomonitoring data.

Production of a specific monoclonal antibody for 1-naphthol based on novel hapten strategy and development of an easy-to-use ELISA in urine samples.

1-naphthol (1-NAP) is the main metabolite of pesticide carbaryl and naphthalene, and is also a genotoxic and carcinogenic intermediate in the synthesis of organic compound, dyes, pigment and pharmaceutical industry. In this work, two novel haptens were designed and synthesized for developing a competitive indirect enzyme-linked immunosorbent assay (ciELISA) method for 1-NAP in urine samples. The assay showed a limit of detection of 2.21 ng/mL and working range from 4.02 ng/mL to 31.25 ng/mL for 1-NAP in optimized working buffer. The matrix effect of samples was eliminated via 15-fold dilution of optimized working buffer. Good average recoveries (102.4%-123.4%) with a coefficient of variation from 11.7% to 14.7% was obtained for spiked urine samples. Subsequent instrument verification test showed good correlation between the results of ciELISA and high-performance liquid chromatography. The developed ciELISA is a high-throughput tool to monitor 1-NAP in urine, which can provide technical support for the establishment of biological exposure level for the exposure to carbaryl, naphthalene and other related pollutants.

Identification of markers of depression and neurotoxicity in pesticide exposed agriculture workers.

Earlier, we reported that chronic exposure to pesticides causes a reduction in the acetylcholinesterase activity and hematological and biochemical alterations in agriculture workers. In continuation with that, the present study aimed to investigate the pesticide-induced neurochemical imbalance and its association with behavior alterations in agricultural workers. A significant increase in depressive symptoms, assessed by the Beck Depression Inventory-II was observed in pesticide exposed workers as compared to the unexposed. A decrease in the level of dopamine in plasma and levels of dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acids, norepinephrine, serotonin, and hydroxyindoleacetic acid in urine was also observed. An increase in the levels of MAO-A and MAO-B has also been observed in these individuals. The decreased levels of neurotransmitters in the blood and urine have been linked with increased levels of MAO and pesticide residues in plasma and urine. Furthermore, these changes were associated with a higher incidence of depression in agricultural workers.

Development of a novel methodology for determination of dialkyl phosphates in human urine using liquid chromatography-tandem mass spectrometry.

In this study a fast and sensitive method was developed for the quantitative determination of six dialkyl phosphates (DAPs) in human urine using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proposed methodology was based on liquid-liquid extraction (LLE) with diethyl ether and ethyl acetate using MgSO4 and NaCl, followed by liquid chromatography and mass spectrometry detection in the selected reaction mode (SRM) with negative electrospray ionization (ESI-). Detection settings were optimized by design of experiments (DoE). Dibutyl phosphate (DBP) was used as internal standard. Several criteria established in the SANTE/11813/2017 guidance document for pesticide residues and analysis in food and feed were used to validate the suggested method: recoveries (R %) between 70 and 120% and coefficients of variation (CV %) ≤ 20%. The procedural limit of quantification (LoQ) was 0.50 ng mL-1 for the six DAPs. The R% and CV% ranges were 82-117% and 3-20%, respectively. In total, 20 spot urine samples from lactating mothers were satisfactorily analyzed by the proposed analytical strategy.

A Quantitative Tandem Mass Spectrometry and Scaled-Down QuEChERS Approach for Simultaneous Analysis of Pesticide Multiresidues in Human Urine.

Multiresidual pesticide determination in a biological sample is essential for an immediate decision and response related to various pesticide intoxications. A rapid and simultaneous analytical method for 260 pesticides in human urine was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). High speed positive/negative switching electrospray ionization (ESI) mode was used, and scheduled multiple reaction monitoring (MRM) was optimized. Three versions of scaled-down QuEChERS procedures were evaluated, and the procedure using non-buffer reagents (magnesium sulfate and sodium chloride) and excluding cleanup steps was selected for optimum pesticide extraction. The limit of quantitation (LOQ) in this methodology was 10 ng/mL for each target pesticide, and correlation coefficient (r²) values of calibration curves were ≥0.988 (linearity range; 10-250 ng/mL). In accuracy and precision tests, the relative error ranges were -18.4% to 19.5%, with relative standard deviation (RSD) 2.1%-19.9% at an LOQ level (10 ng/mL), and -14.7% to 14.9% (RSD; 0.6%-14.9%) at higher concentrations (50, 150, and 250 ng/mL). Recovery range was 54.2%-113.9% (RSD; 0.3%-20.0%), and the soft matrix effect (range; -20% to 20%) was observed in 75.4% of target pesticides. The established bioanalytical methods are sufficient for application to biomonitoring in agricultural exposures and applicable in the forensic and clinic.

A sensitive and accurate vortex-assisted liquid-liquid microextraction-gas chromatography-mass spectrometry method for urinary triazoles.

The development and validation of an innovative, simple, rapid, selective and sensitive vortex-assisted liquid-liquid microextraction-gas chromatography- mass spectrometry (VALLME-GC/MS) method to seven triazole fungicides in urine is reported. The confidence parameters were exhaustive evaluated and linearity (r > 0.99), precision (below 15%, to quality controls, and 20%, to lower limit of quantification), accuracy and robustness were adequate for the analysis of cyproconazole, epoxiconazole, metconazole, tebuconazole, triadimenol, propiconazole and triadimefon. To assess the applicability of the method, analyses were performed in volunteers exposed to triazoles in the last 30 days. The method demonstrated satisfactory analytical performance, with sufficient detectability to be applied as a potential tool to biomonitoring individuals exposed to the seven evaluated fungicides.

Development of a Highly Sensitive Direct Competitive Fluorescence Enzyme Immunoassay Based on a Nanobody-Alkaline Phosphatase Fusion Protein for Detection of 3-Phenoxybenzoic Acid in Urine.

3-Phenoxybenzoic acid (3-PBA) is a human urinary metabolite of many pyrethroid insecticides and can be used as a biomarker to monitor human exposure to these pesticides. A rapid and sensitive direct competitive fluorescence enzyme immunoassay (dc-FEIA) for detecting 3-PBA on the basis of a nanobody (Nb)-alkaline phosphatase (AP) fusion protein was developed. The anti-3-PBA Nb-AP fusion protein was expressed and purified. The 50% inhibitory concentration (IC50) and linear range of dc-FEIA were 0.082 and 0.015-0.447 ng/mL, respectively, with a detection limit of 0.011 ng/mL. The IC50 of dc-FEIA was improved by nearly ten times compared with those of one-step and three-step direct competitive enzyme-linked immunosorbent assay (dc-ELISA). Spiked urine samples were detected by both dc-FEIA and liquid chromatography-mass spectrometry (LC-MS), and the results showed good consistency between the two analysis methods, indicating the reliability of dc-FEIA based on the Nb-AP fusion protein for detecting 3-PBA in urine.

An effective and high-throughput analytical methodology for pesticide screening in human urine by disposable pipette extraction and gas chromatography - mass spectrometry.

In this paper, the use of disposable pipette extraction (DPX) for the determination of pesticides in human urine in possible cases of poisoning is proposed for the first time. The pesticides studied were oxamyl, propoxur, carbofuran, 3­hydroxycarbofuran, carbaryl, methiocarb, terbufos, parathion methyl, malathion, chlorpyrifos and endosulfan. The pipette tip used for the extraction of these compounds was commercially acquired. It has a capacity of 5 mL and contains 20 mg of sorbent material (styrene-divinylbenzene). The optimization of the main parameters that can influence the extraction efficiency of this sample preparation technique was performed with univariate and multivariate approaches. The analytes were separated and identified by gas chromatography coupled to mass spectrometry (GC-MS). The optimal extraction conditions were 5 extraction cycles of 30 s and 5 desorption cycles of 15 s with 250 µL of ethyl acetate. Elution of the extract was performed in a vial containing 100 mg of anhydrous sodium sulfate. The method developed was validated, providing correlation coefficients higher than 0.9955 for all analytes, limits of detection (LOD) of 0.76 to 1.52 µg L-1, limits of quantification (LOQ) of 2.5 to 5.0 µg L-1, relative recoveries of 63 to 118%, intra-day precision of 0.7 to 15.3% and inter-day precision of 4.9 to 13.1%. An effective and rapid method for the analysis of human urine for the identification of possible cases of poisoning by pesticides was successful developed.

Analysis of metabolites of organophosphate and pyrethroid pesticides in human urine from urban and agricultural populations (Catalonia and Galicia).

Isotope dilution solid phase extraction UPLC-MS/MS has been used to develop a robust and rapid methodology for the determination of eight specific metabolites of organophosphate and pyrethroid pesticides in human urine. The use of methanol:acetone (25:75v/v) affords an improvement in extraction efficiency in comparison to these individual solvents. The use of synthetic urine improves selectivity and limits of detection for the calibration straight lines. The method provides detection limits of 14-69pg/ml and 18-19pg/ml for the organophosphate and pyrethroid metabolites, respectively. Urine analyses of these metabolites in urban non-occupationally exposed individuals and farm workers shows that ingestion of these pesticides occurred in both populations. The concentrations of organophosphate pesticide metabolites in the latter were twofold than those from non-exposed populations.

Comparison of questionnaire-based estimation of pesticide residue intake from fruits and vegetables with urinary concentrations of pesticide biomarkers.

We developed a pesticide residue burden score (PRBS) based on a food frequency questionnaire and surveillance data on food pesticide residues to characterize dietary exposure over the past year. In the present study, we evaluated the association of the PRBS with urinary concentrations of pesticide biomarkers. Fruit and vegetable (FV) intake was classified as having high (PRBS≥4) or low (PRBS<4) pesticide residues for 90 men from the EARTH study. Two urine samples per man were analyzed for seven biomarkers of organophosphate and pyrethroid insecticides, and the herbicide 2,4-dichlorophenoxyacetic acid. We used generalized estimating equations to analyze the association of the PRBS with urinary concentrations of pesticide biomarkers. Urinary concentrations of pesticide biomarkers were positively related to high pesticide FV intake but inversely related to low pesticide FV intake. The molar sum of urinary concentrations of pesticide biomarkers was 21% (95% confidence interval (CI): 2%, 44%) higher for each one serving/day increase in high pesticide FV intake, and 10% (95% CI: 1%, 18%) lower for each one serving/day increase in low pesticide FV intake. Furthermore, intake of high pesticide FVs positively related to most individual urinary biomarkers. Our findings support the usefulness of the PRBS approach to characterize dietary exposure to select pesticides.

Urinary dialkylphosphate metabolites and health symptoms among farmers in Thailand.

Using a cross-sectional study, we investigated urinary DAPs levels and health symptoms related to the type of crop cultivation and farm tasks among 84 farmers in Phayao Province of northern Thailand. The results showed that the average of ∑DAPs levels was 10.93 ± 19.64 µg/g creatinine (range 1.48-163.90 µg/g creatinine). The compound found the most was DEP, followed by DETP, DEDTP, DMP, DMTP, and DMDTP, respectively. The type of crop cultivation may be associated with an increasing prevalence of respiratory tract, muscle system, and skin irritation. Farm tasks were associated with an increasing prevalence of muscle system and skin irritation. It was difficult to assess adverse health symptoms associated with urinary DAPs in low levels of exposure; therefore, further investigation is needed using more sensitive biomarkers and more sensitive health symptom measurement.

Associations between pesticide use and respiratory symptoms: A cross-sectional study in Southern Ghana.

BACKGROUND: Indiscriminate use of pesticides is a common practice amongst farmers in Low and Middle Income Countries (LMIC) across the globe. However, there is little evidence defining whether pesticide use is associated with respiratory symptoms. OBJECTIVES: This cross-sectional study was conducted with 300 vegetable farmers in southern Ghana (Akumadan). Data on pesticide use was collected with an interviewed-administered questionnaire. The concentration of seven organochlorine pesticides and 3 pyrethroid pesticides was assayed in urine collected from a sub-population of 100 vegetable farmers by a gas chromatograph equipped with an electron capture detector (GC-ECD). RESULTS: A statistically significant exposure-response relationship of years per day spent mixing/applying fumigant with wheezing [30-60 days/year: prevalence ratio (PR)=1.80 (95% CI 1.30, 2.50); >60days/year: 3.25 (1.70-6.33), p for trend=0.003] and hours per day spent mixing/applying fumigant with wheezing [1-2h/day: 1.20 (1.02-1.41), 3-5h/day: 1.45 (1.05-1.99), >5h/day: 1.74 (1.07-2.81), p for trend=0.0225]; days per year spent mixing/applying fungicide with wheezing [30-60 days/year: 2.04 (1.31-3.17); >60days/year: 4.16 (1.72-10.08), p for trend=0.0017] and h per day spent mixing/applying fungicide with phlegm production [1-2h/day: 1.25 (1.05-1.47), 3-5h/day: 1.55 (1.11-2.17), >5h/day: 1.93 (1.17-3.19), p for trend=0.0028] and with wheezing [1-2h/day: 1.10 (1.00-1.50), 3-5h/day: 1.20 (1.11-1.72), >5h/day: 1.32 (1.09-2.53), p for trend=0.0088]; h per day spent mixing/applying insecticide with phlegm production [1-2h/day: 1.23 (1.09-1.62), 3-5h/day: 1.51 (1.20-2.58), >5h/day: 1.85 (1.31-4.15), p for trend=0.0387] and wheezing [1-2h/day: 1.22 (1.02-1.46), 3-5h/day: 1.49 (1.04-2.12), >5h/day: 1.81 (1.07-3.08), p for trend=0.0185] were observed. Statistically significant exposure-response association was also observed for a combination of activities that exposes farmers to pesticide with all 3 respiratory symptoms. Furthermore, significant exposure-response associations for 3 organochlorine insecticides: beta-HCH, heptachlor and endosulfan sulfate were noted. CONCLUSIONS: In conclusion, vegetable farmers in Ghana may be at increased risk for respiratory symptoms as a result of exposure to pesticides.

Detailed Urinary Excretion Time Courses of Biomarkers of Exposure to Permethrin and Estimated Exposure in Workers of a Corn Production Farm in Quebec, Canada.

Permethrin is a synthetic pyrethroid insecticide widely used in agriculture. Farm workers are thus regularly exposed during spraying season. To help interpret routine biomonitoring results, a proper knowledge of the time courses of biomarkers of exposure is necessary. The kinetics of biomarkers of exposure to permethrin has recently been documented in volunteers exposed to permethrin under controlled conditions but there is a lack of detailed time profiles following real exposure conditions. This study aimed at obtaining data on the excretion time courses of permethrin metabolites in agricultural workers following typical exposure conditions in the field. Twelve workers exposed to permethrin were recruited from a corn production farm in the Montérégie, Quebec, Canada. They provided all their urine voided over a period of 3 days following the onset of a spraying episode of permethrin or work in a treated area. Three major metabolites of permethrin, trans- and cis- 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-l-carboxylic acid metabolites (trans-DCCA, cis-DCCA), and 3-phenoxybenzoic acid (3-PBA), were analyzed. For the applicator, a progressive rise in excretion values was observed with a single peak being reached 29h following the onset of the 3.5h exposure and ensuing elimination with a half-life of 6.4h for trans-DCCA and 8.7h for 3-PBA. In the other workers (supervisor and corn pickers), excretion profiles were generally more compatible with multiple entries in the treated area during the 3-day sampling period and rapid elimination between exposure episodes. In general, 3-PBA was found in slightly higher levels than trans-DCCA, except for the applicator and a harvester. For both trans-DCCA and 3-PBA in a given worker, excretion values expressed as creatinine-normalized concentrations were less variable than those expressed as excretion rates per kilogram body weight. Time-dependent variability in excretion values of workers confirms the need for serial urine sampling of at least two biomarkers of exposure, with minimally pre-exposure, end-of-shift sample the day of onset of exposure, and following morning void.

Relationship between Urinary Pesticide Residue Levels and Neurotoxic Symptoms among Women on Farms in the Western Cape, South Africa.

BACKGROUND: This cross-sectional study aimed to investigate the relationship between urinary pesticide residue levels and neurotoxic symptoms amongst women working on Western Cape farms in South Africa. METHOD: A total of 211 women were recruited from farms (n=121) and neighbouring towns (n=90). Participant assessment was via a Q16 questionnaire, reporting on pesticide exposures and measurement of urinary OP metabolite concentrations of dialkyl phosphates (DAP) and chlorpyriphos, 3,5,6-trichloropyridinol (TCPY) and of pyrethroid (PYR) metabolite concentrations (3- phenoxybenzoic acid (3PBA), 4-fluoro-3-phenoxybenzoic acid (4F3PBA), cis-2,2-dibromovinyl-2,2-dimethylcyclopropane-1-carboxylic acid (DBCA), and the cis- and trans isomers of 2,2-dichlorovinyl-2,2-dimethylcyclopropane-1-carboxylic acid. RESULTS: Median urinary pesticide metabolites were slightly (6%-49%) elevated in the farm group compared to the town group, with 2 metabolites significantly higher and some lower in the farm group. The prevalence of all Q16 symptoms was higher amongst farm women compared to town women. Three Q16 symptoms (problems with buttoning, reading and notes) were significantly positively associated with three pyrethroid metabolites (cis- and trans-DCCA and DBCA), although associations may due to chance as multiple comparisons were made. The strongest association for a pyrethroid metabolite was between problems with buttoning and DBCA (odds ratio (OR)=8.93, 95% confidence interval (CI):1.71-46.5. There was no association between Q16 symptoms and OP metabolites. CONCLUSIONS: Women farm residents and rural women from neighbouring towns in the Western Cape are exposed to OP and PYR pesticides. The study did not provide strong evidence that pesticides are associated with neurotoxic symptoms but associations found could be explored further.

Multi-residue analysis of organic pollutants in hair and urine for matrices comparison.

Urine being currently the most classically used matrix for the assessment of human exposure to pesticides, a growing interest is yet observed in hair analysis for the detection of organic pollutants. The aim of the present work was to develop and to validate multi-residue analytical methods, as similar as possible, in order to determine pesticides and their metabolites in these two biological matrices despite their different nature. The list of parent compounds and their metabolites investigated here consisted of 56 compounds, including organochlorines, organophosphates, pyrethroids, carbamates, other pesticides and polychlorinated biphenyls (PCBs). Two different approaches were necessary for the analysis of non-polar compounds (mainly parents) on one hand and polar analytes (mainly metabolites) on the other hand. In the final procedure, extraction from hair was carried out with acetonitrile/water after sample decontamination and pulverization. Extract was split into two fractions, which were analyzed directly with solid phase microextraction (SPME) injection for non-polar compounds and after derivatization with liquid injection for polar compounds. In urine, non-polar compounds were analyzed directly using SPME. Polar compounds were analyzed after acidic hydrolysis, liquid-liquid extraction with acetonitrile-cyclohexane-ethyl acetate, derivatization and liquid injection. Analysis was performed with gas chromatography tandem mass spectrometry operating in negative chemical ionization (GC-MS/MS-NCI) for all the compounds (non-polar and polar) in the two matrices. In hair, limits of quantification (LOQ) ranged from 0.02 pg/mg for trifluralin to 5.5 pg/mg for diethylphosphate. In urine, LOQ ranged from 0.4 pg/mL for α-endosulfan to 4 ng/mL for dimethyldithiophosphate. The analysis of samples supplemented with standards and samples collected from an animal previously submitted to chronic exposure to pesticides confirmed that all the compounds were analyzable in both hair and urine. In addition, the levels of sensitivity reached with these methods were quite satisfactory with regard to previously published studies, and also considering the number of compounds investigated.

Testing a cumulative and aggregate exposure model using biomonitoring studies and dietary records for Italian vineyard spray operators.

The need for improved tools to estimate the cumulative and aggregate exposure to compounds such as plant protection products (PPPs) is recognised in the EU Regulation 1107/2009. A new model has been developed to estimate the exposure within a population to single compounds or compounds within a Cumulative Action Group, considering dietary and non-dietary sources and multiple exposure routes. To test the model a field study was carried out in Italy with operators applying tebuconazole fungicides, with measurements of dermal exposure collected. Whole urine samples were collected and analysed to provide values for the absorbed dose of tebuconazole, with duplicate diet samples collected and analysed as a measure of dietary exposures. The model provided predicted values of exposure for combined dietary and non-dietary routes of exposures which were compared to the measured absorbed dose values based on urinary analysis. The model outputs provided mean daily exposure values of 1.77 (± 1.96) µg a.s./kg BW which are comparable to measured mean values from the biomonitoring field study of 1.73 (± 1.31) µg a.s./kg BW. To supplement the limited measurement data available, comparisons against other models were also made and found to be comparable.

A review of methods for the analysis of orphan and difficult pesticides: glyphosate, glufosinate, quaternary ammonium and phenoxy acid herbicides, and dithiocarbamate and phthalimide fungicides.

This article reviews the chromatography/MS methodologies for analysis of pesticide residues of orphan and difficult chemical classes in a variety of sample matrixes including water, urine, blood, and food. The review focuses on pesticide classes that are not commonly included in multiresidue analysis methods such as highly polar or ionic herbicides including glyphosate, glufosinate, quaternary ammonium, and phenoxy acid herbicides, and some of their major degradation or metabolite products. In addition, dithiocarbamate and phthalimide fungicides, which are thermally unstable and have stability issues in some solvents or sample matrixes, are also examined due to their special needs in residue analysis.