The environmental and occupational influence of pesticides on male fertility: A systematic review of human studies

Background: The environment plays a key role in male infertility, changing the incidence in various populations, and pesticides are one of the most studied hazards. The use of the latter has never decreased, jeopardizing the safety of workers and the general population. Objective: Our purpose was to summarize the results of studies discussing the association between pesticides and male fertility. Methods: A comprehensive literature search was performed through MEDLINE via PubMed, Scopus, and Web of Science. Only human studies were considered. Semen parameters and DNA integrity were considered to evaluate the effect of pesticides on men. Results: A total of 64 studies that investigated their impact in terms of semen parameters (51 studies) and chromatin and DNA integrity (25 studies) were included. The most frequently affected parameters were total sperm count, sperm motility, and sperm morphology, although a reduction in ejaculate volume and concentration occur in several cases. A tangible worsening of semen quality was associated with organochlorines and organophosphates. Furthermore, pesticide exposure, especially pyrethroids, was related to a higher DNA fragmentation index and chromosome aneuploidy in most articles. Conclusion: The epidemiological evidence supports the association between pesticides and male fertility for workers and the exposed population in terms of semen quality, DNA fragmentation, and chromosome aneuploidy.