National School of Public Health, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil.
National School of Public Health, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil; Biomedical Research Centre Network for Epidemiology and Public Health (CIBERESP), Spain.
Int J Hyg Environ Health. 2016 Aug;219(6):481-97. doi: 10.1016/j.ijheh.2016.05.006. Epub 2016 May 20.
Numerous pesticides are recognized for their endocrine-disrupting properties. Non-persistent pesticides such as organophosphates, dithiocarbamates and pyrethroids may interfere with thyroid function as suggested by animal studies. However, the influence of chronic exposure to these compounds on thyroidal functions in humans remains to be determined. The present study aimed to review epidemiological evidence for an association between exposure to non-persistent pesticides and circulating levels of thyroid hormones (thyroxin [T4] and triiodothyronine [T3]) and thyroid-stimulating hormone (TSH). A systematic review was conducted using MEDLINE, SCOPUS and Virtual Health Library (BVS) databases. Articles were limited to original studies and reports published in English, Portuguese or Spanish. Nineteen epidemiological studies were identified, 17 of which were cross-sectional, 14 were of occupationally exposed workers and 11 used exposure biomarkers. Fungicides and organophosphates (OP) insecticides were the most studied pesticides. Although methodological heterogeneity between studies was noted, particularly regarding study design, exposure assessment, and control of confounding, most of them showed associations with changes in T3 and T4, and/or TSH levels, while results from a few of these are consistent with experimental data supporting the findings that non-persistent pesticide exposure exerts hypothyroid-like effects. However, reporting quality was moderate to poor in 50% of the studies, particularly regarding method of selection of participants and discussion of external validity. Overall, current knowledge regarding the impact of non-persistent pesticides on human thyroid function is still limited. Given the widespread use of pesticides, future research should assess effects of exposure to currently-used pesticides in cohort studies combining comprehensive questionnaire-based assessment and biomarkers. Investigators need to pay particular attention to exposure during critical windows of brain development and exposure in agricultural populations.
许多农药因其具有内分泌干扰特性而被人们所认识。动物研究表明，非持久性农药，如有机磷农药、二硫代氨基甲酸盐和拟除虫菊酯类农药，可能会干扰甲状腺功能。然而，这些化合物的慢性暴露对人类甲状腺功能的影响仍有待确定。本研究旨在回顾非持久性农药暴露与循环甲状腺激素（甲状腺素[T4]和三碘甲状腺原氨酸[T3]）和促甲状腺激素（TSH）水平之间关联的流行病学证据。使用 MEDLINE、SCOPUS 和虚拟健康图书馆（BVS）数据库进行了系统综述。文章仅限于原始研究和以英语、葡萄牙语或西班牙语发表的报告。确定了 19 项流行病学研究，其中 17 项为横断面研究，14 项为职业暴露工人研究，11 项使用暴露生物标志物。杀菌剂和有机磷（OP）杀虫剂是研究最多的农药。尽管研究之间存在方法学异质性，特别是在研究设计、暴露评估和混杂因素控制方面，但大多数研究都表明与 T3 和 T4 以及/或 TSH 水平的变化有关，而其中一些研究的结果与支持非持久性农药暴露产生甲状腺功能减退样效应的实验数据一致。然而，在 50%的研究中，报告质量为中等至较差，特别是在参与者选择方法和讨论外部有效性方面。总的来说，目前关于非持久性农药对人类甲状腺功能影响的知识仍然有限。考虑到农药的广泛使用，未来的研究应该在队列研究中评估目前使用的农药暴露对人体的影响，这些研究应结合综合问卷调查评估和生物标志物。研究人员需要特别注意大脑发育关键时期的暴露和农业人群的暴露。
