A chemical widely used in industry and present in ground water supplies, has now been found in the semen fluid of infertile men, reports a Queen's University research scientist. Dr. Poh-Gek Forkert's study of male mechanics who use trichloroethylene (TCE) in the workplace shows the presence of TCE in their seminal fluid. The team's findings are reported in the March issue of the international journal, Drug Metabolism and Disposition.
Also on the team were researchers from Wayne State University in Detroit, the University of Montreal, the Ottawa Health Research Institute, University of California at Davis, and the London Health Sciences Centre.
TCE is a volatile chemical used extensively in the automotive and metal industries as a de-greasing agent. It is also found in adhesives, lubricants, paints, varnishes, paint strippers, pesticides, spot removers and rug cleaning fluids, and has been detected in both underground and surface water sources.
Already linked to liver, kidney and lung damage, TCE has not until now been linked to reproductive disorders. The National Toxicology Program in the U.S. has estimated that 3.5 million workers are exposed to the chemical.
"Our earlier studies on mice showed damage to reproductive tissue following TCE exposure, and the findings suggested impaired fertility," says Dr. Forkert. "We were interested in determining if there is also a link between TCE exposure and infertility in humans."
In the most recent study, seminal fluid from mechanics who had been exposed to TCE in the workplace - and who had previously been diagnosed with infertility - was analyzed for TCE and its by-products (metabolites). All the semen samples contained TCE and metabolites.
"Taken together, the results of our studies in mice and in humans support the premise that TCE is metabolized in the human reproductive tract, and can adversely affect the normal development of sperm," says Dr. Forkert. "These results have serious implications for potential toxicities from chemicals that may lead to the reported decline in semen quality in humans."
The current occupational exposure limit for TCE is 50 ppm (parts per million). However, this regulation is often difficult to enforce, Dr. Forkert says.
