Companies behind recent recalls of toys and jewelry have told Congress that claims from Chinese suppliers that the products were virtually lead-free did not stand up to scrutiny.

Many said that their suppliers had signed agreements saying they would comply with U.S. standards for lead content. Some even provided copies of lab results.

An official of one Arizona company, though, said in a letter that his firm bought a home lead-testing kit at a hardware store to do its own tests on the 25-cent jewelry it sells. The jewelry failed the tests, and the company later recalled about 123,000 pieces.

Consumer Product Safety Commission tests of another company's toy jewelry found lead levels as high as 96 percent by weight.

A House subcommittee is planning two days of hearings beginning Thursday on this year's recalls of millions of toys and other children's products. The committee has made inquiries of 19 companies.