Pesticides exposure and health risk assessment : a case studyof health effect on male ground-nut farmers’ reproductive system in Kyauk-kan village of Nyaung-u district, Mandalay region, Myanmar

Abstract

Exposure to pesticides affects many body organs including reproductive system. This is the first of its kind pioneering study in Myanmar and the main objective of the present study review was to explore knowledge and practice on safe use of pesticide among farmers and to find out the effects of pesticide on male reproductive system by using biomarkers (semen, serum hormone and blood cholinesterase level) among male farmers in Kyauk Kan village of Nyaung-U District, Mandalay Region, Myanmar and accompanied with nine specific objectives. There were 3 phases, the first phase was cross-sectional study named as observational study, identified the health problems related to pesticide exposure, explored knowledge and practice on safe use of pesticide among ground-nut farmers among both male and female (n=400) in the community by interviewing with questionnaires. Nearly one-third of the respondents were in 38 to 47 years age group. Half of the respondents in this study (53.5%) of the ground-nut farmers in this study have the moderate knowledge level and (79.2%) have poor practice level for pesticide utilization and in this phase I, most of participants of both male and female were difficult to follow the pesticide utilization and used over amount of pesticide instruction. And also there was no association between socio-demographic characteristics of the respondents with knowledge and practice level upon pesticide exposure protection. For the second phase (Phase II), was also a cross-sectional study and named as laboratory study, only 100 male ground-nut farmers who were randomly selected from phase I of male participants, found out the effect of chemicals on male reproductive function of ground-nut farmers who were chronically exposed especially to organophosphate pesticides by using biomarkers in growing and non-growing periods. The average age (±) SD of all was 37.51±9.45 years old and half of the respondents are primary education level. Wilcoxon signed rank test was used for comparing differences between growing and non-growing period among biomarkers and there were statistically significant at pH, viscosity, motility, morphology and sperm count in Semen Analysis, changes at Follicle-stimulating hormone and Testosterone level in Serum Hormonal Analysis and in Blood Cholinesterase test, changes in Haemoglobin Adjusted Acetyl Cholinesterase (HAChE) and Plasma Cholinesterase (PChE) respectively and p-value were less than 0.05 level . Association between biomarkers related with pesticide exposure and work related factors at growing and non-growing period by binary logistic regression analysis and some factors were found with significant association levels (p value <0.05).All the findings of phase II provide further evidence that prolonged exposure to pesticides can cause illness if they are incorporated over a longer period, even if the amounts taken up are relatively small and reported to be associated with reproductive dysfunction by reducing brain acetyl-cholinesterase activity, thus impairing hypothalamic and/or pituitary endocrine functions and reduce the semen quality. Risk assessment was done in last phase (Phase III ) by hand wipe test to assess pesticide residues from dermal exposure and the average daily dose (ADD) of ground-nut farmers at 3.66 ×10-5 mg/kg-day in growing period among randomly selected 30 samples of ground-nut farmers from Phase II. For non-carcinogenic risk characterization, Hazard Quotient (HQ) were used to estimate risk and male ground-nut farmers’ hand at mean was 0.12 and it was less than the acceptable level (HQ ≤1), therefore, ground-nut farmers in this area might not get a higher risk from ground-nut consuming that contaminated with chlorpyrifos. In view of the above findings, male reproductive dysfunction seems to be associated with chronic pesticides exposures and suggestion of handling and practicing of pesticide use and personal protective equipment should be educated and develop pesticide risk reduction program for health promotion and prevention among the farmers to increase health awareness and health concern.