Pesticide Exposure and Thyroid Function in Elementary School Children Living in an Agricultural Area, Brebes District, Indonesia

Background: Children living in agricultural areas are at risk of exposure to pesticides due to their involvement in agricultural activities. Pesticides are one of the chemicals classified as endocrine disrupting chemicals. Objective: To examine the association between exposure to organophosphate pesticides and the occurrence of thyroid dysfunction in children. Methods: This cross-sectional study was conducted on 66 children in two elementary schools located in an agricultural area in Brebes District, Indonesia, in 2015. To determine the pesticide exposure history, we analyzed urine samples and completed a questionnaire. Meanwhile, thyroid function tests were performed. Results: Organophosphate pesticide metabolites were detected in urine samples of 15 (23%) of 66 children. Thyroid stimulating hormone (TSH) levels >4.5 μIU/mL were detected in 24 (36%) children. Free thyroxine (FT4) levels of all participants were normal. The mean TSH level in children with positive urinary organophosphate pesticide metabolites (7.74 μIU/ mL) was significantly (p=0.005) higher than that in those who were negative (4.34 μIU/mL). The prevalence of hypothyroidism in children with positive urinary organophosphate pesticide metabolites (67%) was significantly higher than that in those who were negative (27%; PR 2.4, 95% CI 1.4 to 4.3). Conclusion: A history of pesticide exposure could be used as a risk factor for the occurrence of thyroid dysfunction in children living in agricultural areas.