Concerns over 'female chemicals'

The chemicals can leach into food from food containers

Chemicals in oral contraceptives and food containers harm the development of baby mice and US experts are concerned about the effects in humans.

Male mice exposed to the substances while in the womb developed deformities of the prostate and urethra.

The University of Missouri team published its findings in Proceedings of the National Academy of Sciences.

But experts urged people not to be alarmed and said there was no clear evidence of such problems in humans.

Chemicals

The two man-made chemicals tested by the researchers were ethinylestradiol and bisphenol A.

Ethinylestradiol is found in the oral contraceptive pill and bisphenol A is found in plastic food containers and the lining of tin cans.

The team fed mice doses of these chemicals below the range pregnant women can be exposed to if they continue to use oral contraceptives or eat contaminated food and beverages.

These findings are not conclusive and people should not be concerned Urologist Professor Roger Kirby

The male foetuses of the exposed pregnant mice developed bigger prostates and had narrowing of the urethra - the tube that empties the bladder of urine.

Frederick vom Saal, professor of biological sciences at the University of Missouri, who led the study, said: "During foetal life, small amounts of such oestrogenic chemicals could permanently disrupt cellular control systems and predispose the prostate to disease."

He believes it is possible that these chemicals might lead to prostate cancer.

Professor Roger Kirby, urologist at St George's hospital in London, UK, and spokesman for the charity Prostate Research Campaign, said the new research might help shed light on rising prostate cancer rates.

More research

"We are seeing more prostate cancer, and are also seeing it in younger people. So clearly there could be some environmental factor."

But he cautioned: "These findings are not conclusive and people should not be concerned. It's more of a warning light flashing on the dashboard. We need more research."

He said pregnant mothers might be advised to avoid these chemicals when possible.

Dr Richard Sharpe, from the UK's Medical Research Council Human Reproductive Sciences Unit in Edinburgh, said: "This is not showing that there is an effect on prostate cancer or prostate disease in adults.

"The study is on mice and the findings cannot be extrapolated to humans. The mouse is not a good model for the human in this case.

"During pregnancy, women produce a lot of oestrogen so babies are exposed to this naturally. This does not happen in mice."