Exposure in the womb to a plastics chemical found in a host of products including water bottles, soup cans and paper receipts can increase the risk of prostate cancer, research has suggested.
Scientists in the US studying the growth of human prostate cells in mice found that feeding the animals the chemical bisphenol A (BPA) almost tripled their risk of cancer or precancerous changes.
The doses of BPA given to the mice were relatively the same as those commonly seen in pregnant women.
BPA is widely used to soften plastics, but there have been serious concerns about its ability to mimic the hormone oestrogen. The chemical is now banned from babies’ feeding bottles in the UK and the rest of the EU.
Gail Prins, a professor from the University of Illinois at Chicago, who led the new research, said BPA was “very hard to avoid” despite the fact that it has been linked to several types of cancer in laboratory animals.
She said: “Our research provides the first direct evidence that exposure to BPA during development, at the levels we see in our day-to-day lives, increases the risk for prostate cancer in human prostate tissue.”
The study, published online in the journal Endocrinology, involved implanting human prostate stem cells taken from deceased young adult men into male mice.
Prostate stem cells – immature “incomplete” cells – arise during early foetal development and maintain a man’s prostate tissue throughout his life.
To mimic exposure to BPA during embryonic development, the researchers fed the mice the chemical for two weeks as the implanted stem cells in their bodies transformed into adult prostate tissue.
BPA is widely used to soften plastics, but there have been serious concerns about its ability to mimic the hormone oestrogen
After the tissue had been allowed to mature for one month, the mice were treated with oestrogen to mimic naturally rising levels of the hormone seen in ageing men. Increasing levels of oestrogen in men later in life is one of the known drivers of prostate cancer.
The scientists found that a third of the samples contained either precancerous changes, or full-blown tumours, compared with just 12 per cent of samples from a comparison control group of mice fed harmless oil instead of BPA.