Italian scientists have proved that pollution from road traffic affects male fertility. A study, undertaken by scientists from the University of Naples, looked at young and middle-aged male attendants at motorway toll stations and found decreased sperm quality.
Dr Michele De Rosa compared the semen quality of 85 men who worked at least six hours per day at motorway toll stations with that of 85 men who lived in a nearby area but did not work near traffic. Sperm counts and levels of follicle stimulating hormone (FSH), luteinising hormone (LH) and testosterone were similar between the two groups. But levels of sperm motility and other functions were found to be significantly lower in the tollgate workers, some below World Health Organisation levels. Also, the wives of men who worked at the tollgates took a longer time on average to become pregnant, compared with the other group. Dr De Rosa said 'the sperm of the study group was more feeble and less active so it has a lower fertility potential'.
The research team believes that nitrogen oxides and lead are likely to be the chemicals causing damages to the sperm. While levels of lead in the blood were not as high as found in men with some other jobs, continuous exposure to 'intermediate' levels of lead had impaired the sperm of the tollgate workers. Other impaired sperm functions correlated to damage caused by nitrogen oxides found in traffic fumes. 'Our study demonstrates that continuous exposure to traffic pollutants impairs sperm quality in young and middle-aged men', said Dr De Rosa, adding that 'analysing the potential fertility of these workers after they have been removed from tollgate duty will add other important information'.