Pesticide exposure: the hormonal function of the female reproductive system disrupted?

Although a substantial amount of research has been conducted to associate occupational exposure to pesticides with fertility problems in men [1-4], studies among women are scarce. One reason may be that exposure to pesticides is higher among men, because men usually apply pesticides whereas women get exposed through re-entry activities only. Another reason may be that fertility in women is more difficult to assess than fertility in men. The ovarian cycle has not been as fully explored as the spermatogenesis in men. Ovarian disorders can be caused by a large variety of factors, such as high levels of physical activity, age, stress, smoking, and caffeine use [5-7]. In addition, exposure to chemicals such as benzene and polychlorinated biphenyls (PCBs) can affect the menstrual cycle [8,9]. There are also indications that exposure to particular pesticides may induce ovarian dysfunction. Recently, Farr et al. examined the association between pesticide exposure and menstrual cycle characteristics [10]. They observed that women who worked with pesticides suspected of being hormonally active had a 60–100% increased odds of experiencing long cycles, missed periods, and intermenstrual bleeding compared with women who had never worked with pesticides. In two studies on time-to-pregnancy among female greenhouse workers [11,12], the authors concluded that female workers in flower greenhouses may have reduced fecundability and that exposure to pesticides may be part of the causal chain. In one other study, an increased risk of infertility was observed among women exposed to pesticides or working in industries associated with agriculture [13,14].Some pesticides may interfere with the female hormonal function and thereby cause negative effects on the reproductive system. Most previous studies focused on interference with the estrogen and/or androgen receptor, but the hormonal function can be disrupted in many more ways through pesticide exposure. The aim of the present review is to