Food Packaging Chemicals Linked to Risk of Breast Cancer

Food Packaging Chemicals Are Linked to Greater Risk of Breast Cancer

Chemicals used in food packaging and dental materials may make women vulnerable to breast cancer, according to new research.

A study has linked low levels of the chemicals to the development of vulnerable and hormone-sensitive breast tissue in mice, and experts believe the findings have alarming implications for human health.

During the research, the mammary glands of pubescent female mice developed structurally in a way that made them more likely to develop breast cancer. They also became unusually sensitised to oestrogen, which fuels the vast majority of breast tumours.

Reporting their findings in the latest issue of the journal, Endocrinology, the researchers wrote: "These correlations suggest perinatal (shortly before or after birth) exposure to BPA in particular, and to oestrogens in general, may increase susceptibility to breast cancer."

The research focused on bisphenol-A (BPA), a compound used in large quantities inthe manufacture of plastic food containers, the resins that line food cans, and dental sealants. An estimated six billion pounds of BPA is produced each year worldwide.

Research has shown that the chemical leaches out of products and may be absorbed at low concentrations in the body.

Scientists working with animals have already demonstrated that BPA is potentially damaging to health, but the new study is the first to suggest even very low levels of exposure in the womb may be harmful.

A team of US researchers, led by Professor Ana Soto, from Tufts University School of Medicine in Boston, Massachusetts, administered tiny doses of BPA to pregnant mice.

The doses, 25 and 250 nanograms of the chemical per kilogram of body weight, were designed to mimic the levels humans are likely to be exposed to. A nanogram is a billionth of a gram.

The mice were treated during the latter half of pregnancy, and for about four days after birth. Their offspring were then examined at 30 days old.

One of the most striking effects was a large increase in the number and density of terminal end buds, part of the mammary gland's milk-producing structure. It is here that breast tumours typically form.

The scientists also observed a large drop in the number of cells in this region marked out for death. Programmed cell death, or apoptosis, is a natural defence mechanism that weeds out damaged cells that might turn cancerous.

The second major finding was that animals previously exposed to the higher dose of BPA developed mammary glands that were much more sensitive to oestrogen, which was revealed by the degree to which oestrogen affected the further growth and structure of terminal end buds. Professor Frederick vom Saal, a leading reproductive biologist from the University of MissouriColumbia, said it could be assumed that every member of the population was chronically exposed to BPA.

"This is of tremendous concern, because this is clearly a study that's relevant to human exposure levels to this chemical."

WIDELY USED MATERIALS

Bisphenol-A (BPA) is a chemical building block used primarily to make polycarbonate plastic and epoxy resins.

Polycarbonate plastic is a lightweight, high-performance material used in a wide variety of common products, including CDs, DVDs, electrical and electronic equipment, cars, sports equipment, reusable food and drink containers.

Epoxy resins (ERs) have many uses, including engineering applications such as electrical laminates for printed circuit boards, composites, paints and adhesives, as well as in a variety of protective coatings.

Cured ERs are inert materials used as protective liners in metal cans to maintain the quality of canned foods and beverages.

Source: The Herald; Glasgow (UK)