Their findings appear in the April 30 issue of Human Reproduction.
Researchers from the University of Naples say the results of their study should be an alert to health authorities about the insidious health effects of pollution. They add their findings should prompt research on workers in other jobs who are exposed to similar levels of pollution.
The study investigated the semen quality in 85 men working at motorway tollgates and 85 other men of the same age living in the same area.
Sperm counts and the levels of testosterone, follicle stimulating hormone and luteinizing hormone were all normal in both groups. But all other sperm parameters in the tollgate workers were below World Health Organization levels.
The tollgate workers had significantly lower sperm movement, including forward progression, and much lower levels in other tests of sperm kinetics and function.
"Environmental levels of occupational pollutants, except carbon dioxide, at the tollgates exceeded the maximum legal levels and the workers were exposed to significantly higher levels of nitrogen oxides, sulfur oxides, carbon monoxide and lead than the controls," says study author Dr. Michele De Rosa.
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