LiveScience: Just in time for holiday toy purchases, the Michigan-based Ecology Center has released its second annual consumer guide to what toxic chemicals have been found in toys, including lead, mercury and polyvinyl chloride (PVC).

Healthytoys.org lets consumers search a database of over 1,500 toys that have been tested by an X-ray fluorescence analyzer to find out what's on or near the surface.

This year, lead, which can cause developmental problems for young children, was found in 20 percent of those toys tested. While many of these toys were made in China, one third of the 17 toys manufactured in the U.S. had traces of lead.

Although lead was the most commonly detected chemical, 289 toys showed a detectable level of arsenic, and 62 contained some trace of mercury.

Overall, 62 percent of the tested toys contained low levels of these chemicals, while 21 percent contained no trace of these chemicals.

The U.S. Consumer Product Safety Commission will issue recalls for toys shown to have unhealthy amounts of a certain chemical. These toys should be returned to the manufacturer instead of trashed or donated to a second-hand store to keep heavy metals out of landfills and our drinking water.

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