Impact of Environmental Toxin Exposure on Male Fertility Potential

Sarah C. Krzastek; Jack Farhi; Marisa Gray; Ryan P. Smith


Transl Androl Urol. 2020;9(6):2797-2813. 

In This Article

Does the Timing of Environmental Exposure Affect Fertility Outcomes?

Based on the mechanism by which environmental toxins impact male fertility, particularly through the theorized generation of ROS, it would be intuitive that fetal exposures may lead to longer lasting negative impacts on overall development and future spermatogenesis than would exposure during adulthood. In fact, studies suggest that negative impacts on spermatogenesis may be reversible in adults following removal of exposure to the toxin.[107,135,136] Though outcomes following early exposure to toxins such as phthalates and other endocrine disruptors remain controversial, most studies do show that early exposure is linked to negative developmental outcomes.[28] Specifically, prenatal exposure to cigarette smoking has been associated with decreased sperm concentration and testicular size in adults.[107]

The risk of congenital gonadal malformations as may be seen with testicular dysgenesis syndrome (TDS) appears to be associated with fetal exposure to certain medications, tobacco and alcohol, and other endocrine disruptors. Some evidence suggests that prenatal effects may be irreversible[136] TDS has been proposed as a congenital condition resulting from disrupted testicular development in utero which may lead to a combination of cryptorchidism, hypospadias, and testicular cancer.[136] It is interesting to note that semen parameters have been declining seemingly in correlation with increasing rates of TDS, raising the question as to whether the same environmental exposure that may be linked to impairments in male fertility may also predispose infants to development of congenital gonadal abnormalities. While prospective studies comparing the effects of prenatal to postnatal exposures would be impossible, clearly much more research needs to be done to elucidate the long-term effects of early exposures to environmental toxins on reproductive health.