The warning, from the Center for Science in the Public Interest (CSPI), will serve as yet more negative publicity for packaging companies, many of which use BPA when manufacturing polycarbonates for water bottles, canned soups and drinks, and baby food bottles. "We don't want to tell people not to eat canned beans or tomatoes," said CSPI nutritionist David Schardt. "But at the same time, it makes sense for all parents, and especially pregnant and nursing women, to minimize the exposure of their kids' developing bodies and brains to BPA." The group cites a scientific study published by the National Institute of Environmental Health (NIEH) in August last year, which warned that rats exposed to BPA experienced "a wide range of adverse effects". While the influence on humans has not yet been fully studied, the NIEH said that the changes in the animals indicated that BPA may provoke childhood health problems such as early onset of puberty, obesity, attention deficit hyperactivity disorder (ADHD) and urogenital abnormalities. According to the CSPI, these findings are worrying enough to call for pregnant women to boycott packaging products containing BPA. "In fact, the food industry could make life easier by phasing it out entirely," Schart said. Bisphenol A was first studied in the 1930s as a possible mimic of the hormone estrogen in women. The chemical was later developed to make clear plastics for use in the food industry. Several scientific results have been conducted into the safey of BPA in recent years, and researchers have also linked it to adult health concerns, especially breast and prostate cancer. In 2007, the European Food Safety Authority (EFSA) set a maximum limit for human daily intake of BPA of five milligrams per kilo of body weight per day, but stressed that more studies were needed to link the chemical with human health problems. The Canadian government has also launched a study into BPA, the results of which are expected later this year.