The conclusions of the study are the second blow to the plastics industry over the past week, reports Ahmed ElAmin. As reported in FoodProductionDaily.coma study published by Environmental Health Perspectives claims that normal exposure to phthalates could harm the genital development of unborn baby boys. Phthalates are a chemical group used in plastics packaging,such as bags, to make products flexible and pliable.
The studies potentially exposes plastic packaging companies or their clients to suits from consumers who may have been harmed by the chemicals. The BPA study reinforces previous studies on thechemical. Consumers and lawyers may conclude that the industry might have been negligent in ignoring the previous studies.
In the new BPA study, three US scientists conclude that even low-level exposure to the chemical altersthe mammary glands of female mice grow in a way that makes them more likely to develop breast cancer and also to respond unusually to oestrogen.
"These alterations, were they to take place in humans, could contribute to an increase in breast cancer risk," the scientists state. "Most, if not all, humans have relevant amounts ofbisphenol-A in their bodies."
Humans are exposed to BPA when it leaches from plastic food and beverage containers, dental materials and other products, they note. BPA is used in the production of epoxy resins and polycarbonate plastics.Such plastics are used in many food and drink packaging applications, whilst the resins are commonly used as lacquers to coat metal products such as food cans, bottle tops and water supply pipes. Some polymers used in dental treatment containBPA.
BPA was first shown to be oestrogenic in 1938, in a study using rats. In a 1993 study BPA was found to be oestrogenic in the human breast cancer cell, the scientists state. Another 1995 studyfound that the liquid in some cans of tinned vegetables have been found to contain both BPA and and the related chemical dimethyl bisphenol-A.
The highest levels of BPA were found in cans of peas. BPA was also found in the liquid from cans of artichokes, beans, mixed vegetables, corn and mushrooms. All liquids which contained BPA werefound to be oestrogenic to a human breast cancer cell, the scientists reported.
The current study by is being published in Endocrinology, a journal. The lead scientist in the study is Ana Soto, a professor of cell biology at Tufts University School of Medicine in the US.
In 1997 researchers Fred vom Saal and othersat the University of Missouri-Columbia concluded that BPA was harmful to humans and that its use should be banned. They noted that BPA is also used in the manufacture bottles, from which it leaches atan increasing rate as the bottle ages.
BPA was first identified in the 1930s. In the 1950s, chemists linked BPA together to create polycarbonates and companies began using the chemical in plastics production. BPA is now one of the top 50 chemicalsbeing produced in the US.
Oestrogen refers to a group of steroid hormones, produced mainly by the ovaries, that control the growth and functioning of the female sex organs and other secondary sexual characteristics such as breastdevelopment.