Chemical threats to boys' sex health investigated

Science advisers urge wide-ranging review of how lifestyles affect fertility

James Meikle, health correspondent

Government science advisers want an expert review of the evidence showing how chemicals, working environments, and lifestyles may be affecting the sexual development of boys and their fertility as men.

The government is already funding research on trends in male reproductive health and the possible causes of the reported falls in sperm count and quality, and the increased incidence of malformed genitals and testicular cancer.

But advisers to the Department of Health and the food standards agency want wider-ranging checks made to discover whether the well-documented findings of changes in the sexual characteristics of animals and fish caused by exposure to chemicals can properly be considered significant for humans.

Members of the committee on toxicity of chemicals in food, consumer products and the environment (Cot) believe that the international reviews conducted so far have failed to provide convincing evidence relating to humans.

They believe that scientists from many disciplines should look further than the "endocrine disrupters" - which mimic or disrupt hormones - on which attention has so far concentrated.

These include organochlorine pesticides, potentially cancer-causing dioxins and PCBs, industrial additives in paints, detergents, tin cans and plastics, and chemicals naturally occurring in food.

It is understood that Cot is particularly interested in US research suggesting that women working night shifts are more likely to develop breast cancer.

The theory that, for instance, too much light disrupts hormones and encourages the growth of tumours, could be relevant to sexual development too.

Many of the reported problems in men may result from something happening well before birth.

Four British studies, on which the health and environment departments and the health and safety executive are spending £1.8m, are expected to report soon.

Two of them are analysing data on hypospadia, a congenital abnormality of the penis: the first trying to establish its prevalence in Britain and Europe, the second seeking clues from identified cases in three specific English regions.

This group is questioning the parents of boys with the condition about any exposure to chemicals, at home or work, before their sons were conceived or during pregnancy.

Their use of oral contraceptives and recreational and medicinal drugs, and their water consumption, diet, smoking, alcohol consumption and age and ethnic origin are also being recorded and compared with information on the families of boys without the condition.

The third group is looking at sperm quality in young Scottish-born men, and the fourth, which has funding from the European chemical industry, is examining the differences between fertile and infertile men attending fertility clinics.

This study compares maternal diet, infant feeding methods and job histories, and the men's later occupations.

Environmental health experts and the chemical industry have long disputed whether endocrine disrupters really do cause reproductive disorders and other health problems.

Manufacturers say their products are regulated and chemicals are used at "safe" levels, but there is growing concern about continual low-level exposure and the manner in which chemicals taken within "safe" limits might combine to increase the danger.

Attention is also turning to the dangers as well as the benefits of plant-based diet alternatives to medical treatment of some conditions.