Two animal studies demonstrate that early exposure to a chemical known to leach from baby bottles, the linings of food cans, and other plastic items can trigger illness and even changes in genetic expression. A building block of polycarbonate plastics, bisphenol A (BPA) ends up in food, people, and the environment.
In one of the new studies, the pollutant permanently reprogrammed a gene in pups of mice fed BPA-laced chow.
The mice carried the Agouti gene, which is particularly vulnerable to what are called epigenetic changes. In such effects, hormones and other agents typically remove chemical units known as methyl groups from genes, or add them, interfering with the genes' function. Epigenetically affected Agouti mice, normally lean and brown-haired, become fat and blond (SN: 6/24/06, p. 392).
Randy L. Jirtle and his colleagues at Duke University in Durham, N.C., fed female mice chow that delivered 50 mi