ANN ARBOR, Michigan - One in every three of the more than 1,500 children's toys tested in time for the holiday shopping season have been found to contain "medium" or "high" levels of chemicals of concern such as lead, mercury, cadmium and arsenic.

Lead, bromine and chlorine were found in this piece of low-cost jewelry. Researchers with the Michigan-based nonprofit Ecology Center tested for chemicals that have been associated with reproductive problems, developmental and learning disabilities, hormone problems and cancer; and for those identified by regulatory agencies as problematic.

The testing was conducted with a screening technology - the portable X-Ray Fluorescence analyzer - that identifies the elemental composition of materials on or near the surface of products.

The Ecology Center and partners across the country today released their second annual consumer guide to toxic chemicals in toys, which can be found online at www.HealthyToys.org.

Environmental health groups are holding toy testing events nationwide and urging manufacturers and the federal government to phase out the most harmful chemicals at once.

"There is simply no place for toxic chemicals in children's toys," said Ecology Center's Jeff Gearhart, who led the research.

"Our hope is that by empowering consumers with this information, manufacturers and lawmakers will feel the pressure to start phasing out the most harmful substances immediately, and to change the nation's laws to protect children from highly toxic chemicals," he said.

Lead was detected in 20 percent of the toys tested this year. Lead levels in 54 products were well above the 600 parts per million federal recall standard used for lead paint, and will exceed the U.S. legal limit in February, according to the new Consumer Product Safety Commission regulations.

If the new regulations were in effect today, some of the toys on the shelf this holiday season would be illegal to sell. When children are exposed to lead, the developmental and nervous system consequences are irreversible.

Levels of lead in many of the toys tested were above the American Academy of Pediatrics recommended ceiling of 40 ppm of lead in children's products.

Children's jewelry remains the most contaminated product category, maintaining its spot at the top of HealthyToys.org's "worst" list for a second year.

Overall, jewelry is twice as likely to contain detectable levels of lead as other products, the researchers found.

Numerous Hannah Montana brand jewelry items tested high for lead. HealthyToys.org recommends that consumers avoid low cost children's jewelry.

The website allows searches by product name, brand, or toy type to see if certain toys have toxic chemicals. The newly-redesigned site also lets visitors create a personalized holiday wish list that can be sent to family and friends, and a blog-friendly widget to quickly search the toy ratings.

With millions of toys on the market, HealthyToys.org could not test them all, but visitors to the website can nominate other products to be tested. The most commonly requested items will be tested each week leading up to the holidays.

Through its testing, HealthyToys.org found toys made in China are not the only ones that contain toxic chemicals. Tests show that 21 percent of toys from China and 16 percent of those from all other countries had detectable levels of lead in 2008.

About one-third of the 17 toys tested that were manufactured in the United States showed detectable levels of lead. Two toys had levels above 600 ppm. Among the highest lead levels detected was in a Halloween Pumpkin Pin made in the USA, which showed 190,943 ppm of lead.

Lead is not the only toxic found in the toys. Researchers also found toys containing cadmium, mercury, arsenic, and bromine. Forty-five products tested showed bromine at concentrations of 1,000 ppm or higher, indicating the use of brominated flame retardants - chemicals that may pose hazards to children's health.

Arsenic was detected at levels greater than 100 ppm in 22 products, while 289 products contained detectable levels of arsenic.

Cadmium, a heavy metal, was found above 100 ppm in 30 products, while 38 of products contained detectable levels of cadmium.

Mercury was found above 100 ppm in 14 products, while 62 of products contained detectable levels of mercury.

HealthyToys.org identified products made with polyvinyl chloride, PVC, plastic by measuring their chlorine content.

"PVC is a problematic plastic because it creates major environmental health hazards in its manufacture and disposal and may contain additives, including phthalates, that may pose hazards," the Ecology Center said. Twenty-seven percent of the toys tested this year by HealthyToys.org, excluding jewelry, were made with PVC.

"The good news is that 62 percent (954) of the products tested contain low levels of chemicals of concern, and 21 percent (324) of all products contain no chemicals of concern. These products look and feel no different than other children's products on the shelf," said the Ecology Center. "These findings show that manufacturers can and should make toys free of unnecessary toxic chemicals."