The government of Canada formally declared bisphenol A, a chemical widely used to create clear, hard plastics, as well as food can liners, to be a toxic substance Wednesday. The compound, commonly known as BPA, has been shown to disrupt the hormone systems of animals and is under review in the United States and Europe. Canada's move, which was strenuously fought by the chemical industry, followed an announcement by the government two years ago that it would eliminate the compound's use in polycarbonate bottles used by infants and children. The compound was formally listed as being toxic to both the environment and human health in an official notice published online by the government without fanfare, a noticeable contrast to the earlier baby bottle announcement, which was made by two cabinet ministers. George M. Enei, the director general of science and risk assessment at Environment Canada, one of two government departments that made the designation, said the move would make it easier to ban the use of BPA in specific products through regulations rather than by amending legislation, a cumbersome and slow process. But he said the government's first step would probably be to set limits on how much BPA can be released into the air or water by factories that use the compound. 'This is a step in a journey,' Enei said. 'Once you're on the list, it signals Canada will do something.' While Canadian industry groups did not respond to requests for comment, the decision was condemned by the American Chemical Council. 'Environment Canada's announcement is contrary to the weight of worldwide scientific evidence, unwarranted and will unnecessarily confuse and alarm the public,' Steven G. Hentges, who leads the polycarbonate and BPA group at the council, said in a statement. Rick Smith, the executive director of Environmental Defence, a group that lobbied for the designation, said he hoped that the government would ban BPA from infant formula can linings. 'This toxic designation is a very strong regulatory power that gives them firm legal footing on any number of things,' Smith said. However, Smith agreed that the toxic designation was likely to bring an abrupt end to a variety of food-related uses for BPA, even without new regulations or laws. Refillable polycarbonate bottles for adults -- once popular because of their clarity, light weight and durability -- largely vanished from the market after negative publicity around BPA about two years ago. In addition to food containers, BPA is used to produce some of the epoxies that line cans used for soft drinks, fruits and vegetables. BPA is widely seen as a test case in an era of mounting worry about household chemicals, pollution and the possible links between illness and environmental exposures, especially in fetuses and young children. Many scientists believe that it is an 'endocrine disruptor,' a term applied to chemicals that can act like hormones. Studies using lab animals and cell cultures show that BPA can mimic the female hormone estrogen. Last year, the Endocrine Society, a scientific group, issued a 34-page report that said there was strong evidence of adverse health effects from endocrine disruptors, including harm to the reproductive system, causing malformations, infertility and cancer. In the United States, about half a dozen states have banned BPA in children's products. The federal government has taken no action, saying there is no proof of harm in humans. But health and regulatory agencies have concerns about BPA and have commissioned more studies. In a statement, Dr. Josh Sharfstein, the principal deputy commissioner at the Food and Drug Administration, said the agency was working with the National Institutes of Health 'and other partners to advance scientific understanding of BPA and inform our decisions.' In an extensive study of BPA retained by Canadians' bodies that was published in August, Statistics Canada, a government agency, found that almost no one escaped the chemical and that the highest concentrations of the compound were found in teenagers, with younger children a close second. The presence of a chemical in the body, however, does not necessarily mean it is harmful. Canada's designation is at odds with Europe's approach. Last month, the European Food Safety Authority released an update that concluded that 'data currently available do not provide convincing evidence of neurobehavioral toxicity of BPA.' But France and Denmark have independently imposed temporary bans on some uses of BPA. 