A team of researchers from Indiana University and the University of California have recently conducted a study which showed that a chemical commonly used in plastic bottles and other plastic household products may cause breast cancer. The chemical is known as Bisphenol A (BPA) and in high concentrations it is very likely to stimulate the division of cancer cells.

Bisphenol A (BPA) is a chemical which resembles estrogen and mimics female hormones. Previous studies showed that the particular plastic chemical is not harmless when entering the body of a woman because human organism transforms it into a non-dangerous compound. However, the US researchers who published their findings in the Chemistry & Biology journal proved that the estrogen-like chemical is not completely transformed by our bodies and it still remains a menace for us and our health after being absorbed by our organism.

"We tested whether this chemical modification - the addition of sulfate to BPA - keeps the chemical from being absorbed by breast tumor cells. We've shown that modified versions of bisphenol A likely to be formed in the body do stimulate breast tumor cell growth in vitro. Enzymes present on the surface of breast tumor cells appear to convert the modified BPA back into BPA," explained Biochemist Theodore Widlanski who led the project. Therefore, the chemical found in plastics around the house is dangerous for our health as it stimulates the production and proliferation of breast cancer cells.

In the lab trial, the team exposed cancer cells and enzymes to considerably higher concentrations of BPA and BPA derivatives than those found in common household products and experienced by humans. The concentrations of the chemical used in the study equaled the concentration to which one is exposed throughout his whole lifetime.

Even though the study was only carried out in vitro and not in vivo, the scientists involved in the research cautioned about the results: "We have not shown this process takes place in vivo. We have only demonstrated a possible mechanism that explains what people have been speculating about for years. It doesn't mean that your bottled water is any less safe today than it was yesterday. It just means that if it isn't safe, we might be able to explain why."

"All along we set out to show the opposite - that BPA is not harmful. If any of the answers to our questions had been 'no,' then we would have concluded BPA was not dangerous. But we can't do that, or we can't do it yet," concluded Professor Theodore Widlanski.