Pesticides As Endocrine Disrupters: Identification Of Hazards For Female Reproductive Function

Abstract

Several pesticides are potential endocrine disrupters, with mechanisms including estrogen receptor agonism (chlorinated insecticides), aromatase inhibition (triazoles), interference with pituitary-gonadal axis (chloro-S-riazines) or thyroid (ethylene bisdithiocarbammates). Therefore, female reproductive function may be regarded as a sensitive target for several pesticide groups. Toxicological studies indicate that such compounds may alter different steps of the reproductive cycle, including e.g., the development of the reproductive system as well as ovulation and implantation. Moreover, indirect effects on balance among hormones may be as important as direct actions on target receptors or tissues. However, several phases under endocrine control (e.g., parturition) are different between humans and rodents, thus, direct extrapolation of findings may be difficult on occasion. Consistent epidemiological findings indicate that occupational exposures to certain pesticides (phenoxy herbicides, triazines, glyphosate, thiocarbamates) are associated with miscarriage and reduced fecundity, also upon exposure of the male partner; concurrent factors may increase the risk, such as inadequate protective equipment and woman’s age. As for the general population, the exposure to pesticide residues in vegetable foods appears under control in Europe. However, more data are needed on feed contamination leading to residues in foods of animal origin as well as on exposure through the living environment, e.g., from pest control activities. Moreover, there are no data to evaluate the health implications, if any, of such exposures. Thus, novel approaches are needed, including the development of appropriate biomarkers and biomonitoring programmes. Exposure to pesticide remains a potential concern for reproductive health; accordingly, current efforts of the European Commission toward sustainable use of pesticides, food safety and improved evaluation of environment and health relationships deserve support and implementation.