[The work environment and male reproduction]

This review is focused on the connection between environmental factors in the workplace and male reproduction. Infertility is a problem for 10-15 per cent of Danish couples, and little is known about how large a part is played by environmental factors. It is now accepted that exposure by environmental hazards may result in partial or total infertility. The classic examples are exposure to lead, heat and radioactivity. Recent investigations have shown that occupational exposure to chemical substances such as dibromochloropropane and ethylene dibromide may interfere with spermiogenesis. In Denmark studies have been initiated concerning the connection between welding, lead and organic solvents, and the sperm-specimens. The findings of these studies support the hypothesis that, at levels currently accepted at workplaces, lead interferes especially with the sperm-cell concentration. In a few studies exposure to welding fumes have been found to have an adverse effect on sperm cell concentrations. All the investigations cited are marred by methodological problems. Despite these problems, it is internationally recognised that further studies are urgently needed, as are further epidemiological and methodological investigations in this field.