Association between Occupational Chemical Exposure and Sperm Parameters; A Narrative Review

Background: Infertility is a major problem around the world. The male partner is responsible for half of the infertility. Several factors can affect the male reproductive system and create infertility. Occupational exposure is one of the main factors in male infertility. Present study aimed to review the literature on chemical occupational exposure effects on male fertility. Materials and Methods: For this narrative review online search was conducted on scientific databases including PubMed, Scopus, and Web of Sciences by the following keywords: male fertility/infertility, sperm, occupational, chemical agents, work environment, pesticides painters, farmers, and farmworkers. In this study, we categorized sperm characteristics (quality, count, mobility, morphology, and viability) and reviewed studies (between 1985 – 2022) that assessed chemical occupational effects separately (chemical industries, farmers, and painters) on sperm characteristics. We tried to review the most recently reported studies in this issue and categorized them into subgroups for easy understanding. Result:  Most studies reported a positive association between chemical exposure and defects in sperm parameters. Existing research suggests that the association between industrial life and infertility development is probably reciprocal. Conclusion:  Results of the studies are controversial, and it seems epidemiological investigations cannot approve the harmful effects of some occupational chemical exposure on fertility potential and sperm parameters. During interpreting the results of the studies, it is important to emphasize that the type of chemical mixtures, duration of exposure (chronic exposure to different levels), and number of compounds, physiological and psychological conditions can play a key role.