Scientists like vom Saal argue that BPA and phthalates are different from other environmental toxins like lead and mercury in that these plastic ingredients are endocrine disrupters, which mimic hormones. Estrogen and other hormones in relatively tiny amounts can cause vast changes, so some researchers worry that BPA and phthalates could do the same, especially in young children. Animal studies on BPA found that low-dose exposure, particularly during pregnancy, may be associated with a variety of ills, including cancer and reproductive problems. Some human studies on phthalates linked exposure to declining sperm quality in adult males, while other work has found that early puberty in girls may be associated with the chemicals.
Does that mean even today's minuscule exposure levels are too much? The science is still murky, and human studies are few and far from definitive. So while Canada and the Democratic Republic of Wal-Mart are moving to ban BPA in baby bottles, the Food and Drug Administration maintains that BPA products pose no danger, as does the European Union. Even so, scientists like Mel Suffet, a professor of environmental-health sciences at the University of California, Los Angeles, say avoiding certain kinds of plastics is simply being better safe than sorry.
As researchers continue to examine plastic's impact on our bodies, there's no doubt that cutting down on the material will help the environment. Plastic makes up nearly 12% of our trash, up from 1% in 1960. You can literally see the result 1,000 miles (1,600 km) west of San Francisco in the Great Pacific Garbage Patch, a swirling mass of plastic debris twice the size of Texas. The rising cost of petroleum may get plastic manufacturers to come up with incentives for recycling; current rates stand at less than 6% in the U.S. But the best way to reduce your plastic impact on the earth is simply to use less.
Here's how. You can avoid plastic bottles and toys labeled with the numbers 3 or 7, which often contain BPA or phthalates, and steer clear of vinyl shower curtains and canned foods--especially those with acidic contents like tomatoes. Vom Saal counsels that the cautious should also avoid heating plastic in microwaves. But get rid of the stuff altogether? "It's hard to go all the way," says Haegele, who, 10 months into her experiment, is leading a mostly plastic-free life. Although she still uses a plastic toothbrush, she's experimented with her own toothpaste (made of baking soda, cinnamon and vodka; for the recipe, go to her blog, lifelessplastic.blogspot.com She has used vinegar for conditioner and is searching for a decent shampoo that doesn't come in a plastic bottle. She has tried soaplike bars of shampoo, but they make her hair feel sticky. Plus, they sometimes come wrapped in--you guessed it--plastic.
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