Attorneys general from New Jersey, Delaware, and Connecticuty asked 11 companies that make baby bottles and baby formula containers to no longer use the toxic chemical bisphenol A.
The letters signed by attorneys general from the three states call the chemical, known as BPA, potentially harmful to infants.
"I am alarmed by recent studies confirming that BPA leaches from these products into the foods they hold," Connecticut Attorney General Richard Blumenthal said in the letters. "The preventable release of a toxic chemical directly into the food we eat is unconscionable and intolerable."
Letters are being sent to baby bottle manufacturers Avent America Inc., Disney First Years, Gerber, Handicraft Co., Playtex Products Inc. and Evenflo Co., and formula makers Abbott, Mead Johnson, PBM Products, Nature's One and Wyeth.
Several states are considering restricting BPA use, and some manufacturers have begun promoting BPA-free baby bottles. St. Louis-based Handicraft, maker of Dr. Brown's baby bottles, says on its Web site that its newest bottles do not contain BPA and urges consumers to check its products for symbols that identify bottles that don't contain the chemical. A message was left with the company seeking comment Monday.
Some U.S. stores, such as Wal-Mart Stores Inc. and Toys "R" Us, have already said they're phasing out products that contain BPA. The European Union has said BPA-containing products are safe, but Canada's government has proposed banning the sale of baby bottles with BPA as a precaution.
BPA is used in lightweight, durable plastics. Products include some baby bottles, sippy cups and reusable food and drink containers, such as reusable sports water bottles, Tupperware, compact discs, DVDs, eyeglass lenses and sports safety goggles and helmets.
BPA is also in epoxy resins used to make paints, adhesives and canned food liners.
Animal studies have linked BPA with breast, prostate and reproductive system abnormalities and some cancers, but experts disagree on whether it poses health risks for humans.
Last week, a study by University of Cincinnati scientists, suggested bisphenol A might reduce the effectiveness of chemotherapy treatment for cancer.
The study, led by Nira Ben-Jonathan, PhD, says that BPA actually induces a group of proteins that protect cancer cells from the toxic effects of chemotherapy. The findings are reported in the journal Environmental Health Perspectives and appear online Oct. 8, 2008, ahead of print.
Researchers have suspected that BPA could play a role in cancer because of the chemical's structural similarities to a cancer-promoting compound called diethylstilbestrol (DES). But Ben-Jonathan's team found that BPA isn't exactly mimicking the action of DES.
"These data," study authors write, "provide considerable support to the accumulating evidence that BPA is hazardous to human health."
Government toxicology scientists say that to reduce exposure, people can avoid non-recyclable plastic containers that have the number 7 on the bottom, avoid using these plastics in the microwave and don't wash them in the dishwasher with harsh detergents.