The conclusions of the new study are the third health warning to the plastics industry over the past month. Such studies could potentially expose the companies or their clients to suits from consumers who may have been harmed by the chemicals.
BPA is widely used in plastic food containers, baby bottles, cans, toys and dental sealants.
The latest study indicates that women with a history of miscarriages were found to have higher levels of BPA in their bodies. The results of the study were published in anarticle in the current issue of Human Reproduction magazine.
The scientists, led by Mayumi Sugiura-Ogasawara of the obstetrics and gynaecology department at Nagoya City University Medical School, examined 45 patients who had suffered consecutivemiscarriages three or more times and 32 women with a history of successful pregnancies.
The women that had miscarriages were found to have average BPA levels about three times higher than women who had successfully given birth. The scientists concluded that while a high level of bisphenol A in itself did not predict subsequentmiscarriage, exposure to the chemical is associated with recurrent miscarriage.
The scientists say that their findings are based on a small preliminary study and that further research into the chemical's effect on human reproduction is needed.
As reported in FoodProductionDaily.com a separate study last month indicated that low doses ofBPA could be a contributing factor to the development of breast cancer in women. Another 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.
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. In 1997 researchers Fredvom Saal and others at 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 at an 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 top50 chemicals being 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 asbreast development.