Assessment of dermal exposure to pesticides among farmers using dosimeter and hand washing methods

Pesticide exposure and increased breast cancer risk in women population studies

Pesticide exposure is emerging as a risk factor for various human diseases. Breast cancer (BC) is a multifactorial disease with known genetic and non-genetic risk factors. Most BC cases are attibutable to non-genetic risk factors, with a history of adverse environmental exposures playing a significant role. Pesticide exposure can occur at higher levels in female populations participating in rural activities such as spraying of pesticides in the field, unprotected handling of pesticides at home, and washing of contaminated clothes. Exposure can also be significant in the drinking water of certain populations. Here, we reviewed the literature on women's exposure to pesticides and the risk of BC. We summarize the main links between pesticide exposure and BC and discuss the role of dose and exposure context, as well as potential mechanisms of toxicity. Overall, reports reviewed here have documented stronger associations between higher levels of exposure and BC risk, including documenting direct and acute pesticide exposure in certain female populations. However, discrepancies among studies regarding dose and mode of exposure may result in misunderstandings about the risks posed by pesticide exposure. Plausible mechanisms linking pesticides to breast cancer risk include their impacts as endocrine disruptors, as well as their roles as genotoxic agents, and modulators of the epigenome. Besides establishing links between pesticide exposure and breast cancer, the literature also highlights the critical need to understand the routes and doses of women's exposure to pesticides and the specific associations and mechanisms that are determinants of disease etiology and prognosis.

Mitigation of pesticide residue levels in the exposed dermal regions of occupationally exposed farmworkers by use of personal protective equipment

Unsafe pesticide handling practices with the limited use of personal protective equipment (PPE) by the Indian farming groups lead to an increased risk of exposure to pesticides. Therefore, a community-based follow-up study based on dosimeters, wipes, and hand-wash technique was carried out to evaluate the dermal exposure to pesticides and to analyze the impact of the usage of PPE on minimizing the exposure among the farmworkers of Rangareddy district, Telangana, India. Risk in terms of hazard quotient (HQ), hazard index (HI), and safety analysis as margins of safety was assessed. Farmworkers averaged 18 years of farming experience and showed resistance to adopting good agricultural practices. Ten pesticide residues were detected in concentrations ranging from 0.000 to 246 mg ml-1 in hand-wash, 0.000 to 198.33 ng cm-2 in patch dosimeter, and 0.000 to 1,740 ng cm-2 in wipe samples collected from farmworkers not using PPE. The second phase includes the intervention study results that revealed a significant reduction both in the concentrations and the number of pesticide residues detected in the hand-wash, patch, and wipe samples of the farmworkers who have used the PPE provided to them (p < 0.01). Furthermore, the probabilistic health risk assessment in terms of the HQ values ranged from 0.02 to 1029.82, and HI was >1, suggesting the non-carcinogenic risks associated with dermal exposure to pesticides among them. Additionally, the safety risk assessment in terms of the margin of safety suggests that they follow risky handling practices. The study confirms that farmworkers are exposed to pesticides and emphasizes the significance of using PPE in reducing the risk.

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.

The impact of the use of personal-protective-equipment on the minimization of effects of exposure to pesticides among farm-workers in India

Introduction

Although excessive use of pesticides and unsafe agricultural practices may contribute to numerous intoxications, the role of PPE (personal-protective-equipment) in the minimization of toxicological effects due to pesticide exposure has not been addressed so far. The present study aimed to assess the impact of the use of PPE on the minimization of effects of exposure to pesticides among farm-workers.

Methods

A community-based follow-up study with questionnaire-based survey and field observations was undertaken among farm-workers (n = 180) of Rangareddy district, Telangana, India. Biomarkers of exposure such as cholinesterase activity, inflammatory markers (TNF-α, IL-1β, IL-6, cortisol, and hs-C reactive protein), nutrients (vitamins A, E), liver function (total protein and A/G ratio, AST and ALT levels) were investigated in the laboratory by following the standard protocols.

Results

Farm-workers who had a mean farming exposure of 18 years of and who neither followed safe pesticide handling practices nor used PPE and also showed reluctance to obey good agricultural practices (GAPs). Inhibition of AChE (acetylcholine esterase) with increased inflammation was found among farm-workers as compared to their respective normal values when they have not used PPE. Linear regression statistical analysis revealed a profound effect on inhibition in the AChE activity and various inflammatory markers with the increase in the duration of pesticide exposure. Further, there was no effect of the duration of pesticide exposure on the levels of vitamins A, E, ALT, AST, total protein, and A/G ratio. Further, intervention studies carried out on the use of PPE provided (commercially available and cost-effective) for 90 days showed a significant reduction in the biomarker levels (p < 0.01).

Conclusion

This study demonstrated the importance of the use of PPE during pesticide applications and other agricultural tasks to minimize pesticide-associated adverse health effects.

Dermal measurement of exposure to plant protection products: Actual hand exposure from hand washing vs. wearing cotton gloves

For the authorization of plant protection products, a quantitative non-dietary exposure risk assessment relies on established dermal exposure models, measured mainly using passive dosimetry. Exposure to the hands is determined via hand washing or using cotton gloves as a surrogate for skin. This study compared both methods using operator exposure data available from the Agricultural Operator Exposure Model (AOEM) project report. These data indicate that hand exposure determined using cotton gloves resulted in markedly higher exposure values for all exposure scenarios compared to those determined by hand washes. One explanation for this is that dermal uptake of the residues reduces the amount of residue that can be recovered by hand washing. Uncertainty due to dermal uptake can be addressed by either default assumptions or by specific dermal absorption data. However, this cannot solely account for the large difference observed between the values and is mainly likely to be due to the higher capacity of the cotton gloves vs. human skin to retain residues. The results further indicate that the variability between hand wash samples and cotton glove samples differs between the exposure scenarios. Hence, the level of conservatism related to the use of cotton gloves as surrogate skin remains unknown. In conclusion, this evaluation of the AOEM data indicates that the cotton glove method results in much higher levels of measured hand exposure than the hand wash method. It cannot be excluded that dermal uptake has contributed to that result. However, the findings suggest the higher retention capacity of cotton gloves vs. human skin to be the main impact parameter. The cotton glove method does not provide the results with regards to the protection level that can be expected from the use of protective gloves. Therefore, we believe that the application of the hand wash method is a more accurate measure of exposure levels, if either specific dermal absorption data or, in its absence, default assumptions are applied as adjustment factor.