Workers polish jewelry at a small factory in Yiwu, China. Barred from using lead in children's jewelry because of its toxicity, some Chinese manufacturers have been substituting the more dangerous heavy metal cadmium in charm bracelets. (Eugene Hoshiko/Associated Press)

China's product safety agency will look into findings that dangerously high cadmium levels were found in children's jewelry exported to the U.S. and possibly Canada, an official said Tuesday.

The official, attending a toy safety conference in Hong Kong, said his agency just learned of the results of an Associated Press report published Sunday.

"We just heard about this, and we will investigate," said Wang Xin, a director general for the General Administration of Quality Supervision, Inspection and Quarantine.

Though Wang does not have the authority to order a full-bore inquiry, his comments were the government's first on the matter and show China's nervousness about potential troubles in the U.S., the biggest Chinese export market.

Testing found this Rudolph the red-nosed reindeer charm in Ashland, Ohio, contained high cadmium levels. (Associated Press)

In AP's investigation, it had a lab test 103 pieces of low-priced children's jewelry purchased in several states. They found 12 items with extremely high levels of cadmium, which can hinder brain development in young children, according to recent research, and is known to cause cancer.

Twelve items had cadmium levels of at least 10 per cent by weight. One piece had a startling 91 per cent and others contained more than 80 per cent. The U.S. government regulates cadmium in painted toys but has no restrictions on cadmium in jewelry.

Products removed

On Monday, retail giant Wal-Mart pulled products cited in the AP report from its stores in the U.S. The attorney general of Connecticut promised to investigate suspect costume jewelry.

The worst trinkets with the highest cadmium content came from Wal-Mart and retailer Claire's, both of which have numerous outlets in Canada.

High cadmium levels were also found in cheap jewelry purchased from local dollar stores in the U.S.

Workers assemble jewelry at a small factory in Yiwu, China. (Associated Press)

A New York state legislator called for a ban on the sale of children's jewelry with cadmium. And the top U.S. consumer safety regulator warned Asian manufacturers that cadmium and other toxic material must be kept out of children's charm bracelets, pendants and other baubles.

Health Canada has promised to conduct an investigation that includes sampling and testing children's jewelry for cadmium. Health Canada, which has no power to order a recall of toxic toys, has said it will take appropriate action once the investigation is completed.

The agency also said it's the responsibility of companies to ensure that consumer products they import, sell or advertise meet all requirements of the Hazardous Products Act.

The findings of cadmium contamination come on the heels of a string of product quality scandals in 2007 that caused the U.S. Congress in 2008 to ban toys and other kids products that contain lead — another dangerous and once commonly used material. Cadmium is even more harmful.

A soft, whitish metal that occurs naturally in soil, cadmium is perhaps best known as a component of rechargeable nickel-cadmium batteries, but is also used in pigments, electroplating and plastic. Low-cost jewelry makers find cadmium attractive because it is cheap and easy to work with.

The new lead restrictions has sent factories rushing for substitutes right at the same time that cadmium prices dropped, in part because nickel-cadmium batteries are swiftly being replaced with newer products.

With files from CBC News