tokyo

Japan's Ministry of Health and Welfare announced last week that it is to sponsor a nationwide study of sperm counts. The move follows public concern over the possible effects of endocrine disruptors — man-made chemicals suspected of disrupting human reproductive functions — on male fertility (see above).

Researchers from St Marianna University School of Medicine, Sapporo Medical College, Kanazawa University and Osaka University plan to begin the project later this year.

According to the health ministry, semen samples will be collected from 1,500 men from all over Japan. The samples will be tested to determine the number of sperm per millilitre and the percentage of sperm with normal motility. The researchers also hope to determine whether certain types of food have any effect on sperm levels.

Widespread concern about the effects of endocrine disruptors was triggered last year by the release of a report by the Environment Agency, which listed 67 chemical compounds, such as dioxins and polychlorinated biphenyl compounds (PCBs), that are suspected of mimicking natural sex hormones.

The government has since allocated ¥18 billion (US$152 million) for research into the effects of such compounds on human health (see Nature 392, 748; 1998).