1 Epidemiology Branch, National Institute of Environmental Health Sciences (NIEHS) , Research Triangle Park, North Carolina, USA.
2 Department of Internal Medicine, Division of Diabetes, Endocrinology, and Metabolism, University of Nebraska Medical Center , Omaha, Nebraska, USA.
Environ Health Perspect. 2018 Sep;126(9):97008. doi: 10.1289/EHP3194.
Though evidence suggests that some pesticides may have thyroid-disrupting properties, prospective studies of associations between specific pesticides and incident thyroid disease are limited.
We evaluated associations between use of specific pesticides and incident hypothyroidism in private pesticide applicators in the Agricultural Health Study (AHS).
Self-reported incident hypothyroidism ([Formula: see text] cases) was studied in relation to ever-use and intensity-weighted cumulative days of pesticide use at study enrollment. We estimated adjusted hazard ratios (HRs) and 95% confidence intervals (CI) using Cox proportional hazards models applied to 35,150 male and female applicators followed over 20 y. All models were stratified by state and education to meet proportional hazards assumptions ([Formula: see text] for age x covariate interactions). Models of pesticides that did not meet proportional hazards assumptions were stratified by median attained age (62 y).
Hypothyroidism risk was significantly increased with ever- vs. never-use of four organochlorine insecticides (aldrin, heptachlor, and lindane among participants with attained age [Formula: see text]; chlordane in all participants), four organophosphate insecticides (coumaphos in those [Formula: see text]; diazinon, dichlorvos, and malathion in all participants) and three herbicides (dicamba, glyphosate, and 2,4-D in all participants). HRs ranged from 1.21; 95% CI: 1.04, 1.41 (chlordane) to 1.54; 95% CI: 1.23, 19.4 (lindane in those [Formula: see text]). Hypothyroidism risk was greatest among those with higher intensity-weighted lifetime days of using chlordane, lindane, coumaphos (over age 62), diazinon, permethrin, and 2,4-D.
Our findings support associations between exposure to several pesticides and increased hypothyroidism risk. These findings are generally consistent with prior analyses of prevalent hypothyroidism in the AHS. https://doi.org/10.1289/EHP3194.
尽管有证据表明某些农药可能具有扰乱甲状腺的特性，但关于特定农药与甲状腺疾病发病之间关联的前瞻性研究仍很有限。
我们评估了在农业健康研究（AHS）中私人农药施药者中使用特定农药与甲状腺功能减退症发病之间的关联。
在这项研究中，通过自我报告的新发甲状腺功能减退症（[Formula: see text]例），来研究在研究入组时曾使用过农药和累计使用强度的天数与发病之间的关系。我们使用 Cox 比例风险模型来估计调整后的风险比（HR）和 95%置信区间（CI），这些模型适用于 35150 名男性和女性施药者，随访时间超过 20 年。所有模型均按州和教育程度分层，以满足比例风险假设（[Formula: see text]个年龄与协变量的交互作用）。不符合比例风险假设的农药模型按中位达到年龄（62 岁）分层。
与从未使用过农药的人相比，曾使用过四种有机氯杀虫剂（艾氏剂、七氯和六氯苯，在达到年龄 [Formula: see text]的参与者中；氯丹在所有参与者中）、四种有机磷杀虫剂（蝇毒磷，在达到年龄 [Formula: see text]的参与者中；敌敌畏、敌百虫和马拉硫磷在所有参与者中）和三种除草剂（麦草畏、草甘膦和 2,4-D，在所有参与者中）的人，甲状腺功能减退症的发病风险显著增加。HR 范围为 1.21；95%CI：1.04，1.41（氯丹）至 1.54；95%CI：1.23，19.4（六氯苯，在达到年龄 [Formula: see text]的参与者中）。在一生中使用氯丹、六氯苯、蝇毒磷（年龄超过 62 岁）、敌敌畏、氯菊酯和 2,4-D 的强度加权使用天数较高的人群中，甲状腺功能减退症的发病风险最高。
我们的研究结果支持接触几种农药与甲状腺功能减退症发病风险增加之间的关联。这些发现与 AHS 中之前对甲状腺功能减退症的分析基本一致。https://doi.org/10.1289/EHP3194.
