Levels and determinants of pesticide exposure in re-entry workers in vineyards: results of the PESTEXPO study

Dislodgeable Foliar Residue Measurements and Assessment of Dermal Exposure to Captan for Workers in Apple Orchards

Captan dislodgeable foliar residues (DFRs) were determined by following the applications of this fungicide in an apple orchard. The study comprised an investigation of the variability of captan DFR values and 14 days of DFR monitoring to assess kinetic modeling. A method combining solid-phase microextraction (SPME) gas chromatography and high-resolution mass spectrometry (GC-QTOF-MS) was developed for the quantification of captan residues from DFR aqueous extracts. The results evidenced that (1) sampling parameters such as the position of the tree in a row and the height of foliar significantly influenced captan DFR levels (247-1450 ng·cm-2), highlighting the need to implement a comprehensive sampling strategy; (2) the DFR captan dissipation kinetic model best matched with a biphasic one, with half-lives of DFRcaptan of 3.4 and 12.8 days, respectively, for the initial rapid phase 1 decline (day 0-5) and the slower phase 2 decline phase (day 6-14). Furthermore, through DFR measurements, the potential dermal exposure (PDE) of workers was assessed using transfer coefficients (TCs) from the literature. Compared to the acceptable operator exposure levels (AOELs), the results showed that the re-entry interval for captan may not sufficiently protect workers whose arms, hands, and legs are not covered.

Association of immunotoxicological indices with lung cancer biomarkers in poultry, grape, and rose farming workers

Exposure to occupational hazards like dust, pesticides, diesel emission particles, or physical hazards in the agricultural sector is known to cause adverse health effects on farm workers. Our study aimed at addressing the association of immunomodulatory status with plasma levels of lung cancer biomarkers in farming population, attempting to recognition of vulnerable farming group. Blood samples from apparently healthy 51 chicken husbandry, 19 grape orchard, and 21 rose greenhouse workers were subjected to evaluate plasma levels of two representative lung cancer biomarkers, pro-gastrin releasing peptide (Pro-GRP) and cytokeratin fragment 19 (CYFRA 21-1). Peripheral blood mononuclear cells obtained from farmers were used for natural killer (NK) cell phenotyping and cytokines (interferon-gamma, IFN-γ and interleukin-13, IL-13) profiling in the culture supernatant. Compared to the rose greenhouse farmers, the grape orchard and chicken husbandry workers revealed a significantly upregulated plasma Pro-GRP and CYFRA 21-1 level. A low proportion of NK cells was observed among the female grape orchard workers and a lowered IFN- γ:IL-13 ratio was seen in the grape and chicken husbandry workers than the rose workers. Our findings imply that grape orchard and chicken husbandry workers have more disturbed immune homeostasis implicated with augmentation in the levels of lung cancer biomarkers than the rose greenhouse workers.

Acute Pesticide Poisoning in Tobacco Farming, According to Different Criteria

BACKGROUND

Brazil is one of the world's largest pesticide consumers, but information on pesticide poisoning among workers is scarce.

OBJECTIVE

To evaluate acute pesticide poisoning among tobacco growers, according to different criteria.

METHODS

This was a two-step cross-sectional study with 492 pesticide applicators. It used a 25 question pesticide-related symptoms (PRS) questionnaire and medical diagnosis for comparison with toxicological assessment. Associations were evaluated using Poisson regression.

RESULTS

10.6% reported two or more PRS, while 8.1% reported three or more. Furthermore, 12.2% received a medical diagnosis of poisoning. According to toxicologists, possible cases accounted for 14.2% and probable cases for 4.3%. PRS increased during the period of greater exposure. Those exposed to dithiocarbamates, sulfentrazone, pyrethroids, fipronil and iprodione exhibited more PRS. The number of exposure types, multi-chemical exposure, clothes wet with pesticides and spillage on the body/clothes were associated with acute poisonings. All criteria showed sensitivity greater than 79% for probable cases but only greater than 70% for medical diagnosis when compared to possible cases, presenting substantial Kappa agreement.

CONCLUSION

The prevalence of acute pesticide poisoning is much higher than officially recorded. Trained physicians can screen for pesticide poisoning. It is necessary to improve workers' education to reduce pesticide use and exposure to them.

A Critical Scoping Review of Pesticide Exposure Biomonitoring Studies in Overhead Cultures

The exposure of operators, workers, residents and bystanders to pesticides is of high potential concern. Yet, reports on pesticide residues in the environment and near treated fields often spark debates if such findings might indicate a health risk. Although the underlying models are considered conservative, there are only limited field data on systemic exposure available. As a first step to improve the situation, we conducted a scoping review of state-of-the-art pesticide exposure biomonitoring studies in operators, workers, residents or bystanders. In contrast to existing reviews, we focused on target cultures of potential high pesticide exposure such as tree-grown produce, vine or hops. The search was conducted in Web of Science, Scopus and PubMed. Out of 17 eligible articles, a total of 11 studies met our search criteria, and 6 of them quantified the systemic exposure of humans. The analysis revealed that exposure was mainly driven by application of pesticides and reentry work, resulting in a higher exposure of operators and workers than of residents and bystanders. In nearly all cases, the systemic exposure was below the relevant toxicological reference values. The studies were subsequently analyzed to identify key criteria for a reliable design of a biomonitoring study on pesticide exposure.

Cancer incidence in agricultural workers: Findings from an international consortium of agricultural cohort studies (AGRICOH)

BACKGROUND

Agricultural work can expose workers to potentially hazardous agents including known and suspected carcinogens. This study aimed to evaluate cancer incidence in male and female agricultural workers in an international consortium, AGRICOH, relative to their respective general populations.

METHODS

The analysis included eight cohorts that were linked to their respective cancer registries: France (AGRICAN: n = 128,101), the US (AHS: n = 51,165, MESA: n = 2,177), Norway (CNAP: n = 43,834), Australia (2 cohorts combined, Australian Pesticide Exposed Workers: n = 12,215 and Victorian Grain Farmers: n = 919), Republic of Korea (KMCC: n = 8,432), and Denmark (SUS: n = 1,899). For various cancer sites and all cancers combined, standardized incidence ratios (SIR) and 95% confidence intervals (CIs) were calculated for each cohort using national or regional rates as reference rates and were combined by random-effects meta-analysis.

RESULTS

During nearly 2,800,000 person-years, a total of 23,188 cancers were observed. Elevated risks were observed for melanoma of the skin (number of cohorts = 3, meta-SIR = 1.18, CI: 1.01-1.38) and multiple myeloma (n = 4, meta-SIR = 1.27, CI: 1.04-1.54) in women and prostate cancer (n = 6, meta-SIR = 1.06, CI: 1.01-1.12), compared to the general population. In contrast, a deficit was observed for the incidence of several cancers, including cancers of the bladder, breast (female), colorectum, esophagus, larynx, lung, and pancreas and all cancers combined (n = 7, meta-SIR for all cancers combined = 0.83, 95% CI: 0.77-0.90). The direction of risk was largely consistent across cohorts although we observed large between-cohort variations in SIR for cancers of the liver and lung in men and women, and stomach, colorectum, and skin in men.

CONCLUSION

The results suggest that agricultural workers have a lower risk of various cancers and an elevated risk of prostate cancer, multiple myeloma (female), and melanoma of skin (female) compared to the general population. Those differences and the between-cohort variations may be due to underlying differences in risk factors and warrant further investigation of agricultural exposures.

Pesticide exposure of workers in apple growing in France

Objective

Although apple trees are heavily sprayed, few studies have assessed the pesticide exposure of operators and workers in apple orchards. However, these data are crucial for assessing the health impact of such exposures. The aim of this study was to measure pesticide exposure in apple growing according to tasks and body parts.

Methods

A non-controlled field study was conducted in apple orchards in 4 regions of France during the 2016 and 2017 treatment seasons. Workers’ external contamination and their determinants were assessed over 156 working days corresponding to 30 treatment days, 68 re-entry days and 58 harvesting days. We measured pesticide dermal contamination during each task and made detailed observations of work characteristics throughout the day. Captan and dithianon were used as markers of exposure.

Results

The median dermal contamination per day was 5.50 mg of captan and 3.33 mg of dithianon for operators, 24.39 mg of captan and 1.84 mg of dithianon for re-entry workers, and 5.82 mg of captan and 0.74 mg of dithianon for harvesters. Thus, workers performing re-entry tasks, especially thinning and anti-hail net opening, presented higher contamination, either equal to or higher than in operators. For these last ones, mixing/loading and equipment cleaning were the most contaminating tasks. Most of the contamination was observed on workers’ hands in all tasks, except for net-opening in which their heads accounted for the most daily contamination.

Conclusions

This study highlights the importance of taking indirect exposures into account during re-entry work in apple growing.

Association between occupational and environmental pesticide exposure in Cukurova region by hair and blood biomonitoring

This study assesses association between occupational and environmental pesticide exposure on pesticide applicators directly exposed to pesticides and inhabitants of the Cukurova region by analyzing blood and hair samples. Hair and blood samples were collected from 132 volunteers, 66 of whom are pesticide applicators, and the rest are non-farmer residents, in 10 villages nearby the Ceyhan River between March and June in 2017. Samples were then analyzed via the liquid chromatography-tandem mass spectrometer. As the analysis result, a total number of 31 pesticides were detected in hair samples, whereas a total number of 15 pesticides were observed in blood samples. Twenty of the pesticides (64.5%) detected in the hair and 3 (20%) detected in the blood were significantly higher in the applicators than the non-farm residents. Also, 5 pesticides (16.1%) observed in the hair and 7 observed (46.6%) in the blood were banned pesticides. This study investigated the pesticide exposures on people living in the region via hair and blood samples. Our study revealed that, in addition to individuals who are occupationally exposed to pesticides, individuals from all parts of the society, especially those living in the agricultural region, have a certain level of pesticide exposure.

Domestic use of pesticides during early periods of development and risk of testicular germ cell tumors in adulthood: a French nationwide case-control study

BACKGROUND

Testicular germ cell tumours (TGCT) are the most frequent cancers in young men in developed countries and their incidence rate has doubled worldwide over the past 40 years. Early life exposures to pesticides are suspected to increase TGCT risk. Our research aimed at estimating adult TGCT risk associated with parental domestic use of pesticides during early periods of child development.

METHODS

We conducted a case-control study of 304 TGCT cases, aged 18-45 years old, recruited in 20 French university hospitals, and 274 controls frequency-matched on hospital and birth year. Participants' mothers provided information on their domestic use of pesticides from 1 year before start of pregnancy to 1 year after their son's birth, for gardening activities, treatment of indoor plants, pets, wood and mold, and pest control. Odds ratios (OR) for TGCT (overall and by histological subtype) and 95% confidence intervals (CI) were estimated using conditional logistic regression.

RESULTS

Prevalence of reported domestic use of pesticides was 77.3% for insecticides, 15.9% for fungicides and 12.1% for herbicides. While no association was found for any use of insecticides (OR = 1.27, CI = 0.80-2.01) or herbicides (OR = 1.15, CI = 0.67-2.00), elevated risks of TGCT overall (OR = 1.73, CI = 1.04-2.87) and non-seminoma subtype (OR = 2.44, CI = 1.26-4.74) were observed for any use of fungicides. When specific purposes were examined, using fungicides and/or insecticides for woodwork (OR = 2.35, CI = 1.06-5.20) and using insecticides on cats and dogs (OR = 1.95, CI = 1.12-3.40) were associated with increased risk of non-seminoma subtype. We found no association for seminoma subtype.

CONCLUSIONS

Although recall bias may partially explain the elevated ORs, our study provides some evidence of a positive association between domestic use of pesticides during early periods of development, particularly fungicides and risk of adult TGCT and non-seminoma. Given the common domestic use of pesticides in France, further research on TGCT risk is warranted.

Occupational hazards, health costs, and pesticide handling practices among vegetable growers in Pakistan

Disregarding protective measures when handling pesticides in agricultural production imposes increased health risks and health costs on farmers as well as degrades the natural ecosystem. In Pakistan, where agriculture is the prime occupation in rural communities, there is overwhelming evidence of indiscriminate use of hazardous pesticides by farmers without taking adequate precautions. Using cross-sectional data, we examined personal protection and health costs to vegetable growers due to pesticide exposure and determinants of farmers' pesticide handling practices. The theory of averting behavior was used, and the possible factors affecting farmers' adoption of safety equipment and of disposal methods for pesticide containers were estimated using a logit model. Health effects (P < 0.05) and farmers' protection and health costs (P < 0.01) are found as important determinants of farmers' adoption of safety equipment and of disposal methods for pesticide containers. The mean protection and health cost of pesticide exposure per farmer per vegetable season in 2019 was US $3.60. Analytical outcomes indicate that safe and recommended pesticide handling practices are needed to be introduced through adequate integrated pest management (IPM) training programs and by improving farmers' formal education. Thus, creating awareness through IPM training programs among vegetable growers and enhancing formal education to encourage the adoption of precautionary measures and safe disposal methods for pesticide containers may reduce health risks and health costs. Findings imply that adoption of adequate pesticide handling practices would further help reduce occupational hazards and promote sustainable agriculture in Pakistan.

Medico-administrative data combined with agricultural practices data to retrospectively estimate pesticide use by agricultural workers

This work is part of a global project aiming to use medico-administrative big data from the whole French agricultural population (~3 millions), collected through their mandatory health insurance system (Mutualité Sociale Agricole), to highlight associations between chronic diseases and agricultural activities. At the request of the French Agency for Food, Environmental and Occupational Health & Safety (ANSES), our objective was to estimate which pesticides were probably used by each agricultural worker, in order to include this information in our analyses and search for association with diseases. We selected five databases to achieve this objective: the Graphical Land Parcel Registration (RPG), the French Agricultural Census, "Cultivation Practice" surveys from the Agriculture ministry, the MATPHYTO crop-exposure matrix and the Compilation of Phytosanitary Indexes from the French Public Health Agency. A geographical grid was designed to use geographical location while maintaining worker anonymity, dividing France into square tracts of variable surface each containing a minimum of 1500 agricultural workers. We developed an automated algorithm to predict each individual potential exposure by crossing her/his occupational activity, the geographical grid and the RPG to deduce cultivation practices and use it as a gateway to estimate pesticides use. This approach allowed drawing, from administrative data, a list of substances potentially used by each agricultural worker throughout France. Results of the algorithm are illustrated at collective level (descriptive statistics for the whole population), as well as at individual level (some workers taken as examples). The generalization of this method in other national contexts is discussed. By linking this information with the health insurance databases, this approach could contribute to the agricultural workers health surveillance.

Carpal Tunnel Syndrome Among Male French Farmers and Agricultural Workers: Is It Only Associated With Physical Exposure?

Background

Exploratory study to investigate whether co-exposure to physical wrist stressors and chemicals is associated with carpal tunnel syndrome (CTS) in French male farmers and agricultural workers.

Methods

Cross-sectional study of 711 men aged 30–65 years and working as either farmers or agricultural workers in 2009–2010 within a cohort covered by the French Agricultural Workers' and Farmers' Mutual Benefit Fund. CTS and exposure to physical wrist stressors and chemicals were assessed using a self-administered questionnaire. Associations between CTS and personal/medical factors, exposure to physical wrist stressors, exposure to chemicals, and co-exposure to physical wrist stressors and chemicals were studied using multivariate logistic regression models.

Results

Forty-four men {5.6% [95% confidence interval (CI) 4.0–7.7]} reported that they had suffered from unilateral/bilateral CTS during the last 12 months. CTS was associated with age, current smoking [odds ratio (OR) = 2.1 (1.0–4.5)], and exposure to physical wrist stressors [OR = 2.6 (1.1–5.9)]. An association was found between CTS and co-exposure to physical wrist stressors and chemicals [OR = 3.3 (0.8–14.3), p = 0.044] in comparison with the no-exposure group.

Conclusions

This exploratory study shows an association of CTS with exposure to biomechanical wrist stressors in male farmers and agricultural workers and suggests an association of CTS with co-exposure to physical wrist stressors and chemicals. Owing to the limitations of the study, this result must be confirmed by a prospective study with objective assessments of the outcome and exposure before drawing conclusions on the possible synergistic effects of mechanical stressors and chemicals on the impairment of the median nerve.

Hair as a matrix to evaluate cumulative and aggregate exposure to pesticides in winegrowers

INTRODUCTION

Vineyard is a crop where a large number of pesticides are applied; exposure to pesticides may occur in farmers and the general population living close to the treated area. This work aimed to investigate hair as a matrix for the assessment of cumulative and aggregate exposure to pesticides in potentially exposed individuals.

METHODS

Twenty agricultural workers (AW), 4 agricultural worker relatives (AR), and 5 research staff members (RS) were involved in the study. Hair samples were collected before and after the application season (PRE- and POST-EXP samples) to obtain 18 paired samples. Records with the name and the quantity of applied pesticides were obtained; twenty-seven pesticides were measured in hair by solvent extraction and LC-MS/MS.

RESULTS

During the study season, AW applied 14 different pesticides with median amount ranging from 12 to 7200 g. The most popular pesticides were dimethomorph, penconazole, cyazofamid, fenamidone and quinoxyfen, applied from 94 to 69% of AW. In AW, in PRE-EXP samples the majority of used pesticides was detectable (with detection rates from 6 to 88%), with median concentrations of few pg/mg hair; in the POST-EXP samples the frequency of detected values increased (from 25 to 100%), with median concentrations up to two orders of magnitude higher. In AR, most pesticides were quantifiable only in POST-EXP samples and with lower concentration in comparison with AW; in RS, in both PRE- and POST-EXP samples only a few pesticides were quantifiable with very low levels. In AW, a linear correlation (r = 0.682 on log-transformed data, p < 0.01) was found between the total amounts of applied pesticides during the season and their concentration in hair.

CONCLUSION

The study shows that the majority of assessed pesticides was incorporated into hair of AW and AR. The increased frequency of detection and level at the end of the season and the correlation between pesticide in hair and the amount of applied pesticides, reinforce the use of hair for quantitative biomonitoring of cumulative exposure to pesticides.

Agricultural exposures to carbamate herbicides and fungicides and central nervous system tumour incidence in the cohort AGRICAN

BACKGROUND

Pesticides exposures could be implicated in the excess of Central Nervous System (CNS) tumors observed in farmers, but evidence concerning individual pesticides remains limited. Carbamate derivative pesticides, including herbicides and fungicides (i.e. (thio/dithio)-carbamates), have shown evidence of carcinogenicity in experimental studies in animals. In the French AGRICAN cohort, we assessed the associations between potential exposures to carbamate herbicides and fungicides and the incidence of CNS tumors, overall and by histological subtype.

METHODS

AGRICAN enrolled 181,842 participants involved in agriculture. Incident CNS tumors were identified by linkage with cancer registries from enrollment (2005-2007) until 2013. Individual exposures were assessed by combining information on lifetime periods of pesticide use on crops and the French crop-exposure matrix PESTIMAT, for each of the 14 carbamate and thiocarbamate herbicides and the 16 carbamate and dithiocarbamate fungicides registered in France since 1950. Associations were estimated using proportional hazard models with age as the underlying timescale, adjusting for gender, educational level and smoking.

RESULTS

During an average follow-up of 6.9 years, 381 incident cases of CNS tumors occurred, including 164 gliomas and 134 meningiomas. Analyses showed increased risks of CNS tumors with overall exposure to carbamate fungicides (Hazard Ratio, HR = 1.88; 95% CI: 1.27-2.79) and, to a lesser extent, to carbamate herbicides (HR = 1.44; 95% CI: 0.94-2.22). Positive associations were observed with specific carbamates, including some fungicides (mancozeb, maneb, metiram) and herbicides (chlorpropham, propham, diallate) already suspected of being carcinogens in humans.

CONCLUSIONS

Although some associations need to be corroborate in further studies and should be interpreted cautiously, these findings provide additional carcinogenicity evidence for several carbamate fungicides and herbicides.

Innovative isotopic method to evaluate bioaccumulation of As and MTEs in Vitis vinifera

The transfer of metal and metalloid trace elements (MTEs) from contaminated soil to grapevines is a major issue for grape consumption and for the associated health risks. Based on an isotopic approach, we shed light on the concept of MTE bioavailability. The bioavailable fractions are identified by using the Sr-isotope ratio as a proxy for MTEs. This allows us to differentiate three soil reservoirs: the 'current available fraction' in soil water, the 'reserve available fraction' stored in mineral phases of the soil fractions, and the 'non-available fraction'. The reserve available fraction, representing 10 to 60% of bulk soil depending on the MTE, includes the exchangeable, carbonates, humic substance and oxides fractions. The ⁸⁷Sr/⁸⁶Sr isotopic signatures of grape berries and vine leaves show an additional source of MTEs, which is imported by foliar uptake and can contribute up to 10% of the MTEs in leaves. In addition, root-uptake and translocation rates show high accumulation rates of Co, Sn and Cu, and low ones for As, Sb, Zn and Cd. A daily intake between 1 and 3 kg of (dry grapes) would reach the benchmark dose level for a 0.5% (BMDL_0.5). While such a daily intake of grapes is unreasonable, consumption of other local vegetables and fruit would contribute to the daily intake. Hence, a chronic arsenic exposure is of great concern for human health in mining areas. We outline the importance of geochemical tracers, such as Sr isotopes, when determining the transfer and translocation of MTEs in plants. Our method presents a high-precision evaluation of the bioavailability and bioaccumulation of MTEs, and a better understanding of these processes in plants, thus leading to a better assessment of the environmental risk on human health.

Assessment of penconazole exposure in winegrowers using urinary biomarkers

Penconazole (PEN) is a fungicide used in agriculture. The aim of this work was to evaluate the exposure to PEN in vineyard workers focusing on urinary biomarkers. Twenty-two agricultural workers were involved in the study; they were investigated during PEN applications and re-entry work, performed for 1-4 consecutive working days, for a total of 42 mixing and applications and 12 re-entries. Potential and actual dermal exposure, including hand exposure, were measured using pads and hand washes. Urine samples were collected starting before the first application, continuing during the work shift, and ending 48 h after the last shift. The determination of PEN in dermal samples and PEN metabolites in urine was performed by liquid chromatography tandem mass spectrometry. Dermal potential body exposure and actual total exposure showed median levels ranging from 18 to 3356µg and from 21 to 111 µg, respectively. Urinary monohydroxyl-derivative PEN-OH was the most abundant metabolite; its excretion rate peaked within 24 h after the work shift. In this period, median concentrations of PEN-OH and the carboxyl-derivative PEN-COOH ranged from 15.6 to 27.6 µg/L and from 2.5 to 10.2 µg/L, respectively. The concentration of PEN-OH during the work shift, in the 24 h after and in the 25-48 h after the work shift were correlated with actual body and total dermal exposure (Pearson's r from 0.279 to 0.562). Our results suggest that PEN-OH in the 24 h post-exposure urine is a promising candidate for biomonitoring PEN exposure in agricultural workers.

Occupational predictors of urinary dialkyl phosphate concentrations in Mexican flower growers

Background Flower growers have high potential for exposures to pesticides. Occupational factors, such as tasks performed, the production method (organic or conventional), the use of personal protective equipment (PPE), and workplace characteristics influence the intensity of pesticide exposure. Objective To evaluate occupational characteristics affecting urinary concentration of dialkylphosphate (DAP) metabolites of organophosphate pesticides among a group of Mexican floricultural workers. Methods A questionnaire was administered to 117 workers who also provided a first morning urine sample. According to tasks performed and the production methods, pesticide contact was defined as low, medium, or high. PPE use was categorized as acceptable, fairly acceptable, and unacceptable. Urinary concentration of DAP metabolites were determined using gas-liquid chromatography. Association between occupational characteristics and DAP urinary concentrations was assessed by means of linear regression models. Results After adjusting for potential confounders, the workers in the medium and high contact categories had significantly higher DAP concentrations than those in the low contact category (β: 0.3, CI 95%: 0.1-0.5). Greenhouse workers had greater DAP concentrations than outdoors workers (β: 0.3, CI 95%: 0.1-0.5). Compared with non-acceptable use of PPE, acceptable use of PPE was associated with lower DAP concentrations (β: -0.4, CI 95% -0.6 to -0.1). Conclusion Improved safety training is needed for correct PPE usage, especially among flower growers who use conventional pest control methods and who work in a greenhouse environment.

Ambient mass spectrometry: Direct analysis of dimethoate, tebuconazole, and trifloxystrobin on olive and vine leaves by desorption electrospray ionization interface

A new field of application for a relatively new mass-spectrometric interface such as desorption electrospray ionization was evaluated. For this purpose, its behavior was tested versus quantitative analysis of dimethoate, trifloxystrobin, and tebuconazole directly on olive and vine leaves surface. The goal was workers exposure assessment during field re-entry operations since evidence suggests an association between chronic occupational exposure to some agrochemicals and severe adverse effects. Desorption electrospray ionization gave good response working in positive ionization mode, while numerous test were necessary for the choice of a unique blend of spray solvents suitable for all 3 substances. The best compromise, in terms of signal to noise ratios, was obtained with the CH₃ OH/H₂ O (80:20) mixture. The obvious difficulties related to the impossibility to use the internal standard were overcome through an accurate validation. Limits of detection and quantitation, dynamic ranges, matrix effects, and intraday precisions were calculated, and a small monitoring campaign was arranged to test method applicability and to evaluate potential dermal exposure. This protocol was developed in work safety field, but after a brief investigation, it was find to be suitable also for food residue evaluation.

Central nervous system tumors and agricultural exposures in the prospective cohort AGRICAN

Studies in farmers suggest a possible role of pesticides in the occurrence of Central Nervous System (CNS) tumors but scientific evidence is still insufficient. Using data from the French prospective agricultural cohort AGRICAN (Agriculture & Cancer), we investigated the associations between exposure of farmers and pesticide users to various kinds of crops and animal farming and the incidence of CNS tumors, overall and by subtypes. Over the 2005-2007, 181,842 participants completed the enrollment questionnaire that collected a complete job calendar with lifetime history of farming types. Associations were estimated using proportional hazards models with age as underlying timescale. During a 5.2 years average follow-up, 273 incident cases of CNS tumors occurred, including 126 gliomas and 87 meningiomas. Analyses showed several increased risks of CNS tumors in farmers, especially in pesticide users (hazard ratio = 1.96; 95% confidence interval: 1.11-3.47). Associations varied with tumor subtypes and kinds of crop and animal farming. The main increases in risk were observed for meningiomas in pig farmers and in farmers growing sunflowers, beets and potatoes and for gliomas in farmers growing grasslands. In most cases, more pronounced risk excesses were observed among pesticide applicators. Even if we cannot completely rule out the contribution of other factors, pesticide exposures could be of primary concern to explain these findings.

A French crop-exposure matrix for use in epidemiological studies on pesticides: PESTIMAT

Pesticide exposure assessment is a key methodological issue for epidemiological studies. The history of pesticide has proven difficult to obtain from individuals' report because of the wide range of active ingredients (AIs). We developed a crop-exposure matrix, which intends to reconstitute parameters of pesticide exposure in France since 1950. PESTIMAT is composed of tables crossing crops and AIs by year and providing the following metrics: (1) probability (proportion of farmers having used the AIs); (2) frequency (number of treatment days); and (3) intensity (application rate of the AIs in kg/ha). Metrics were obtained by the combination of six sources: (i) registration information from the Agriculture Ministry; (ii) information from agricultural bodies on products marketed; (iii) agricultural recommendations by the Plant Health Protection body; (iv) treatment calendars provided by farmers; (v) data from associations of farmers; and (vi) data from the industry. To date, 529 AIs usable between 1950 and 2010 are included in PESTIMAT: 160 fungicides; 160 herbicides; and 209 insecticides. When combined with duration and determinants of intensity, the metrics in PESTIMAT will make it possible to calculate exposure scores and to search for dose-effect relationships, an important criterion for causality judgment in epidemiology.

Occupational exposure to pesticides as a possible risk factor for the development of chronic diseases in humans (Review)

It is well known that pesticides are widely used compounds. In fact, their use in agriculture, forestry, fishery and the food industry has granted a huge improvement in terms of productive efficiency. However, a great number of epidemiological surveys have demonstrated that these toxic compounds can interact and exert negative effects not only with their targets (pests, herbs and fungi), but also with the rest of the environment, including humans. This is particularly relevant in the case of workers involved in the production, transportation, preparation and application of these toxicants. Accordingly, a growing body of evidence has demonstrated the correlation between occupational exposure to pesticides and the development of a wide spectrum of pathologies, ranging from eczema to neurological diseases and cancer. Pesticide exposure is often quite difficult to establish, as many currently used modules do not take into account all of the many variables that can occur in a diverse environment, such as the agricultural sector, and the assessment of the real risk for every single worker is problematic. Indeed, the use of personal protection equipment is necessary while handling these toxic compounds, but education of workers can be even more important: personal contamination with pesticides may occur even in apparently harmless situations. This review summarises the most recent findings describing the association between pesticide occupational exposure and the development of chronic diseases.