title: Occupational causes of male infertility.
abstract: OBJECTIVE
  To highlight and discuss the new evidence on occupational and environmental risk to male reproductive function.
  
  
  RESULTS
  Semen quality following occupational exposure to boron (an acknowledged experimental reproductive toxicant) and benzene, and new evidence on low-level environmental exposure to widespread xenobiotics with endocrine actions.
  
  
  CONCLUSIONS
  The naturally occurring semimetal boron is an experimental reproductive toxicant, but now a Turkish semen study corroborates earlier evidence that high-level occupational exposure is not toxic to human spermatogenesis. It seems that human exposure levels are below the levels that cause reproductive toxicity in rodents. On the contrary, there is now ample evidence that the carcinogenic substance benzene may cause chromosomal aberrations in sperm at very low exposure levels. This includes chromosomal deletions that are known to cause infertility, mental retardation and congenital malformations. This research highlights the need to scrutinize the chemicals for possible male-mediated developmental toxicity. Several occupational studies are addressing adult testicular function in men exposed to chemicals that may interfere with endocrine signalling such as bisphenol A and phthalates, but findings are rather inconsistent and it remains to be established whether these widespread chemicals have any impact on male fertility.
authors: Department of Occupational and Environmental Medicine, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark. jpb@bbh.regionh.dk
authors: Jens P E
authors: JP
authors: Bonde
mesh_terms: D000818:Animals; D001554:Benzene / Q000633:toxicity; D001559:Benzhydryl Compounds / Q000633:toxicity; D006801:Humans; D007248:Infertility, Male / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D009676:Noxae / Q000633:toxicity; D009784:Occupational Diseases / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology*; D016273:Occupational Exposure / Q000009:adverse effects; D010636:Phenols / Q000633:toxicity; D010795:Phthalic Acids / Q000633:toxicity; D012306:Risk; D000098826:Bisphenol A Compounds
chemical_list: D001554:Benzene; D001559:Benzhydryl Compounds; D009676:Noxae; D010636:Phenols; D010795:Phthalic Acids; C006780:bisphenol A; D000098826:Bisphenol A Compounds