Infertility affects roughly 15% of couples, but previous studies have found that about 50% of male infertility is potentially correctable. Wellness experts and medical health professionals define infertility as the inability to conceive after one year of unprotected intercourse. 192 men who were part of couples that were “sub-fertile”, or with a lower ability to become pregnant than normal, healthy couples, took part in the observational study, which looked at environmental exposure to organochlorine chemicals.
Led by Melissa Perry ScD MHS, professor and chair of the Department of Environmental and Occupational Health at the George Washington School of Public Health and Health Services, the researchers analysed blood samples for the presence of chemicals such as PCBs and p,p’-DDE, which is the main metabolite of the insecticide DDT. The investigators also assessed semen samples for a condition where sperm cells have an abnormal number of chromosomes, known as sperm disomy. Though all men have a certain number of sperm with such abnormalities, the team found that those with higher levels of PCBs and DDE had significantly higher rates.
Though PCBs were once used for all manner of products, including electrical equipment, adhesives, oil-based paint, caulking, plastics, carbonless copy paper and floor finish, use of the chemical has been banned by the EPA since 1979, so why is exposure still a problem? Many PCB products are being dumped into landfills not designed to handle hazardous waste, or poorly maintained hazardous waste sites that leak and release the contaminants into the air and water. However, human exposure to the toxin appears to be primarily through food.
Dr Perry commented, ‘This research adds to the already existing body of evidence suggesting that environmental exposure to certain chemicals can affect male fertility and reproduction. We need to further understand the mechanisms through which these chemicals impact sperm.’ She added, ‘While we cannot avoid chemicals that already persist in the environment, it is imperative that decisions about putting biologically active chemicals into the environment need to be made very carefully, because there can be unanticipated consequences down the road.’