As plastic ages or is exposed to heat or stress, it can release trace amounts of some of its ingredients. Of particular concern are bisphenol-a (BPA), used to strengthen some plastics, and phthalates, used to soften others.These chemicals are used in hundreds of household items; BPA is in everything from baby bottles to can linings, while phthalates are found in children‘s toys as well as vinyl shower curtains. They enter your body through the food, water and bits of dust you consume, or are simply absorbed through your skin.BPA and phthalates are endocrine disrupters, which mimic hormones. Estrogen and other hormones in relatively tiny amounts can cause vast changes, so researchers worry that BPA and phthalates could do the same, especially in young children.To cut down on your exposure, avoid plastic bottles and toys labeled with the numbers 3 or 7, which often contain BPA or phthalates, and canned foods, especially those with acidic contents like tomatoes. You should also avoid heating plastic in microwaves.