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Manmade chemicals known as phthalates may be lurking in your children's toys. Manufacturers use them to soften the plastic found in various playthings - washable books, teething rings, and, yes, even rubber duckies. Studies have shown that exposure to these substances as the body is still developing can lower testosterone levels in boys, cause male genital birth defects, and lead to early puberty in girls. Confronted by these threats to public health, Congress attached a phthalate ban to the Consumer Product Safety Improvement Act. The law, which passed in July, bans six phthalates considered the most toxic from toys for children under 12 years old; these same chemicals have already been eliminated from children's toys in the European Union since 1999.

The $1.4 billion phthalate industry, led by the American Chemistry Council, a trade group of chemical manufacturers, opposed the bill on the grounds that most of the scientific findings are from tests conducted on laboratory animals, not on humans. But Sarah Janssen, an NRDC science fellow, believes today's body of research offers justification for the new rules; studies show more than 95 percent of the U.S. population have traces of phthalates in their bodies. "Banning phthalates in toys seems like a no-brainer," says Janssen, who twice testified before Congress about the chemicals' dangers. The prohibition won't go into effect until early 2009. To remain phthalate-free this gift-giving season, purchase toys that are labeled as such (Gerber and LEGO offer them) or that are made from cloth or wood.