Association between pesticide exposure and thyroid cancer: A systematic review and meta-analysis.

Thyroid cancer (TC) is one of the most common endocrine malignancies worldwide, yet the association between pesticide exposure and TC has not been systematically summarized. This study aimed to elucidate the relationship between pesticide exposure and TC, focusing on insecticides, herbicides, and fungicides. Considering exposure to different pesticide types, we employed fixed- or random-effects meta-analysis to calculate odds ratios (ORs) and their corresponding 95 % confidence intervals (CIs) based on the degree of heterogeneity. The results indicated a positive association between exposure to insecticides (OR = 1.07, 95 % CI: 1.02-1.12), herbicides (OR = 1.10, 95 % CI: 1.04-1.17), and fungicides (OR = 1.21, 95 % CI: 1.13-1.29) and TC. Furthermore, sex-based analysis revealed that the risk of TC due to pesticide exposure was higher in females (OR = 1.52, 95 % CI: 1.26-1.84) than males (OR = 0.95, 95 % CI: 0.87-1.03). Specifically, insecticide exposure was positively associated with TC in females (OR = 1.46, 95 % CI: 1.18-1.80), while in males, herbicide exposure was negatively associated with TC (OR = 0.85, 95 % CI: 0.75-0.96), whereas fungicide exposure was positively associated (OR = 1.38, 95 % CI: 1.04-1.84). Pesticide exposure is a risk factor for TC, with females exhibiting a higher risk than males.