Chemical exposure to foetal mammary gland can up breast cancer risk

Exposure of common plastic chemical on the developing mammary gland in the womb is likely to spurt the growth of breast cancer in women, reveals a new study.Bisphenol A (BPA) is a well-known endocrine disruptors chemical found in a variety of food containers, including polycarbonate plastic water bottles and can linings.

It can have numerous adverse health effects in humans and studies have proved that it can cross the placenta in the womb. "The exposure in the womb to endocrine disruptors such as BPA may be a main factor responsible for the increased incidence of breast cancer in women," said lead researcher Lucia Speroni, research associate at Tufts University in Boston, US.

The findings of the animal study showed that BPA directly affects the mammary gland of mouse embryos. The change to embryonic mammary tissue occurs at a dose that is comparable to that of humans' environmental exposure to BPA. The team extracted mammary buds, the early developing form of the mammary gland, from 14-day-old mouse embryos.

They then grew the mammary buds in culture dishes for five days and the investigators observed its development in real time.
The researchers tested various BPA doses and compared the effects with estrogen and found that BPA increased the growth of the mouse mammary bud at doses, which were environmentally relevant.

The researchers also hope to test other hormonally active chemicals that potentially cause breast cancer."We now have a way to test the impact of endocrine-disrupting chemicals on the development of the mouse mammary gland at different doses and obtain results in less than a week," Speroni said. The results were presented at the ongoing Endocrine Society's 98th annual meeting in Boston.