Plasma pesticide residues-serum 8-OHdG among farmers/non-farmers diagnosed with lymphoma, leukaemia and breast cancers: A case-control study.

BACKGROUND: A hospital-based cross-sectional case-control study was conducted to investigate the association between exposure through various pesticide residues detected in the plasma and serum 8-OHdG levels among farmers and non-farmers diagnosed with leukaemia, lymphoma and breast cancers and compare the same with healthy controls with no cancer and no exposure. METHODOLOGY: The present study was conducted among the farmers and non-farmers visiting a regional tertiary cancer care hospital in Hyderabad, Telangana State, India. Data were collected by administering a pre-tested questionnaire through an interview followed by the collection of blood samples which were analyzed for pesticide residues using LC-MS/MS while the serum levels of 8-OHdG were measured using ELISA. Data were analyzed using SPSS 24. RESULTS: The pesticide residues detected were chlorpyrifos, dimethoate, malathion, phosalone, and quinalphos which were approved and recommended for their use on the crops that were cultivated by the farmers in their plasma samples along with banned pesticide residues like monocrotophos, diazinon, and dichlorvos among farmers diagnosed with all three types of cancers while the non-farmers and healthy controls were not detected with any such residues. In addition, farmers diagnosed with leukemia had higher levels of all the pesticide residues in their plasma than those diagnosed with lymphoma and breast cancers. Further, a significant difference was also observed between profenofos residues in plasma and serum 8-OHdG levels. CONCLUSION: In the present study, though the farmers diagnosed with three types of cancers were detected with various types of pesticide residues analysed, only residues of profenofos showed a significant difference with serum levels of 8-OHdG suggesting the need for an in-depth follow up molecular studies in a larger cohort to assess the possible association between 8-OHdG levels with the pesticide residues among the exposed.

Genetic Polymorphism in Xenobiotic Metabolising Genes and Increased Oxidative Stress among Pesticides Exposed Agricultural Workers Diagnosed with Cancers.

BACKGROUND: Oxidative stress combined with nullity of xenobiotic metabolizing GSTT1/GSTM1/CYP2E1 genes may increase the susceptibility of agricultural workers to adverse health effects including cancer. The present study was conducted to determine; the prevalence of polymorphisms in GSTM1, GSTT1 and CYP2E1 genes, serum 8-hydroxy-2'-deoxygunosine levels, and the role of these markers in risk of cancer among agricultural workers occupationally exposed to pesticides. METHODS: A total of 360 participants, of which 180 belonging to farming group diagnosed with leukemia (n=60), lymphoma (n=60) and breast cancers (n=60), 90 in non-farming group diagnosed with similar cancers and the other 90 as healthy controls with neither history of occupational exposure nor diagnosed with any type of cancers were recruited. Following the questionnaire survey, serum 8-OHdG and genetic polymorphisms in the three genes were determined using ELISA and PCR methods respectively. RESULTS: The results of the study revealed that farm workers carrying GSTT1 null genotype had increased risk for lymphoma (OR = 5.34; 95% CI = 1.80-15.82) and breast cancer (OR=4.04; 95% CI = 1.24-13.07). For farm workers carrying GSTM1 null genotype, the risk was six-fold for breast cancer (OR = 6.88; 95% CI =1.88-25.99). Further, there found a significant difference between 8-OHdG and nullity of CYP2E1 among the farm workers diagnosed with leukemia. CONCLUSION: The findings of the present study suggest that the polymorphisms in detoxifying genes among farm workers occupationally exposed to pesticides and the oxidative stress may likely be responsible for triggering the mechanism of malignancy.

Knowledge, attitude and practices related to pesticide usage among farmers: Findings from a hospital based cross-sectional study.

BACKGROUND: In India, where agriculture is the prime occupation among the rural population, farmers are extensively using pesticides in crop production without taking adequate precautions. OBJECTIVE: The current study aimed to examine pesticide usage patterns, usage of personal protective equipment (PPE), knowledge on pesticide toxicity, and attitude towards occupational safety among farmers diagnosed with leukaemia (n = 60), lymphoma (n = 33), and breast cancer (n = 30) visiting a tertiary cancer care hospital in Hyderabad, India. METHODS: Face-to-face interviews were conducted using a pre-tested questionnaire and the data collected were analysed with statistical software SPSS 23. RESULTS: The survey revealed that the participants had an average of 19.6 years of farming experience and women were predominantly involved in the mixing of pesticides and other agricultural work apart from spraying. All of them were not using any PPE and the majority of them did not have any knowledge on the route of exposure, toxicity symbols, and safe handling of pesticides. Statistical analysis showed no significant association between educational status and knowledge, attitude and practices (p > 0.05). CONCLUSION: Even though the majority of the farmers were educated, their lack of adequate knowledge on pesticides had enabled them to adopt risky behaviours in handling and storage of pesticides. There is a need for continuous training programs for farmers to promote awareness and minimize the hazards of occupational exposure.

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-1ß, 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.

Residual Dialkyl Phosphate Metabolite Concentrations of Organophosphate Pesticides Among Indian Farmworkers: Implication of Exposure and Hazard Assessment.

OBJECTIVE: Biomonitoring of urinary dialkyl phosphate (DAP) metabolites, a sensitive biomarker to assess pesticides exposure and also to study the impact of the use of personal protective equipment (PPE). METHODS: A preintervention-postintervention study to biomonitor dimethylphosphate, diethylphosphate, diethylthiophosphate, and diethyl-dithiophosphate using liquid chromatography with tandem mass spectrometry among Indian farmworkers (n = 120). RESULTS: Dimethylphosphate was detected in all samples at a mean concentration of 74.91 µg · L -1 (17.616 µg · g -1 creatinine), whereas diethylthiophosphate and diethyl-dithiophosphate were detected in 88% and 82% of samples, respectively, among farmworkers who adopted unsafe pesticide-handling practices. Intervention studies showed a significant reduction in the urinary DAP metabolites detected among the farmworkers using PPE provided to them ( P < 0.01). CONCLUSIONS: Study confirms the exposure to pesticides among farmworkers and highlights the importance of the use of PPE to minimize exposure.

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.

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

Inappropriate use of pesticides followed by unsafe handling practices to control the insect infestation among the farming groups in developing countries has resulted in a high exposure risk. The use of personal protective equipment is also negligible among Indian farmers due to their affordability to access the same. Very little research has been conducted to establish an exposure assessment procedure through dermal penetration of pesticide residues. Therefore, to quantify the contamination of pesticide residues through dermal exposure along with detailed field observations and pesticide management practices, a field study was conducted in Rangareddy district, Telangana, Southern India, to assess the dermal exposure based on dosimeter and hand washing methods. The analytical method was modified and validated in-house for performance parameters such as limit of detection, quantification, linear range, recovery, and precision. The potential dermal exposure values ranged from 0.15 to 13.45 µg, while a reduction was found in exposure levels as actual dermal exposure values ranged from 0 to 0.629 µg. Contamination through hand washing was the major contributor to overall dermal exposure. Statistical analysis revealed a significant difference in the exposed dermal regions of the leg and torso after the use of PPE. Penetration factor for each anatomical region and risk evaluation in terms of the Margin of Safety implies unsafe handling of pesticides. The findings of the present study confirm the increased exposure to organophosphate pesticides among operators and highlight the importance of the use of protective measures, especially among those that focus on dermal exposure mitigation.