Mounting evidence of BPA harm



plastic bottle

Credit: Wikimedia

- Advertisement -

New research adds to the mounting evidence that several chemicals used to make plastics have adverse health and environmental effects.

Among these chemicals is Bisphenal A (BPA), a compound used to make the clear plastic in reusable items such as sport water bottles, baby bottles, and the lining in some food and beverage cans.

The research was published in a special section in the October issue of the American journal Environmental Research*, which presented six studies describing dangerous effects of plastic chemicals, including the controversial BPA.

Commenting on the research, Frederick Vom Saal, curators' professor of biology at the University of Missouri-Columbia, US, said this is the first time that a collection of research covering such a wide array of topics regarding BPA and other harmful chemicals in plastic has been published.

He said the accumulating evidence of these chemicals presents a "scary array of cancer, brain damage, behavioural changes, behavioural problems, abnormalities of the reproductive system and disease.

When these plastic items are heated, or weathered from any uses and washes, the chemical bonds of BPA are broken down, causing the chemical to leach into the food or beverage that the plastic contains.

The older a product gets and the more it is heated or washed, the more this leaching occurs.

Dangerous mimicry

Animal studies have found that once in the body, BPA can mimic the sex hormone estrogen. While the body naturally produces estrogen, changes in levels of estrogen or estrogen-mimicking chemicals can cause severe health problems.

Previous studies on laboratory animals also show that BPA causes brain damage, various cancers and reproductive problems. But whether or not this translates to similar adverse effects in humans is hotly debated

According to Vom Saal, some of the new research on BPA shows that normal gender-based differences in the brains of rats is eradicated after exposure to BPA - further evidence that fetal exposure to BPA can affect brain function and behaviour.

More research needed

Michael Shelby, director for National Toxicology Program's Centre for the Evaluation of Risks to Human Reproduction - an American governmental organisation that recently released an extensive report on BPA - said that there is currently no evidence that BPA has adverse health effects on humans.

But, Shelby said, because there is evidence that doses similar to levels experienced by humans affects laboratory animals, "we cannot dismiss the possibility that [adverse effects] may occur in humans. More research is needed to resolve this possibility."

*The original story incorrectly stated the journal's name.