LOS ANGELES — Walmart said Wednesday it is pulling an entire line of Miley Cyrus-brand necklaces and bracelets from its shelves after tests performed for The Associated Press found the jewelry contained high levels of the toxic metal cadmium.

In a statement issued three hours after AP’s initial report of its findings, Walmart said it would remove the jewelry, made exclusively for the world’s largest retailer, while it investigates. The company issued the statement along with Cyrus and Max Azria, the designer who developed the jewelry for the 17-year-old “Hannah Montana” star.

Walmart Stores Inc. had learned of cadmium in the Miley Cyrus jewelry, as well as in an unrelated line of bracelet charms, back in February, based on an earlier round of testing conducted at AP’s request, but had continued selling the items. It said as recently as last month that it would be too difficult to test products already on its shelves.

In its statement, Walmart did not say whether it would also remove the bracelet charms.

Exactly how many of the items have been sold was unclear. The charms — also available exclusively at Walmart stores — were sold under the name “Fashion Accessories,” though Walmart has not said when they began appearing on shelves. The Miley Cyrus jewelry hit stores in December.

Long-term exposure to cadmium can lead to bone softening and kidney failure. It is also a known carcinogen.

Cadmium in jewelry is not known to be dangerous if the items are simply worn. Concerns come when youngsters bite or suck on the jewelry, as many children are apt to do.

“We are removing all of the jewelry from sale while we investigate its compliance with our children’s jewelry standard,” Walmart said.

That was a reference to a policy Walmart voluntarily implemented last month, under which suppliers are required to prove their products contain little cadmium, or else Walmart would not accept them.

The company’s policy of not checking products already on the shelves appears to have changed. In its statement, Walmart said it reviewed children’s jewelry and pulled “the few products that did not” comply with its new testing regimen.

Cadmium in children’s jewelry became a public concern in January when the AP published the results of an investigation that showed items at Walmarts and other large chains were as much as 91 percent of the toxic metal by weight.

That testing was conducted by Jeff Weidenhamer, a chemistry professor at Ashland University in Ohio. In February, Weidenhamer was asked to provide to Walmart headquarters detailed results of tests on items he bought at Walmarts as part of testing he had done for AP. Those items included 10 of the charms and three pieces from the Cyrus line.

To judge the continued availability of pieces that Walmart has known were contaminated, AP dispatched reporters throughout the country last month to buy any of the 13 items they could find. The packaging said they were made in China; all were bought for $6 or less.

All but one of the 13 were on store shelves in the eight states where AP reporters looked. Contrary to Walmart’s statement Wednesday, which said the Cyrus jewelry was sold in the women’s apparel section, AP reporters found the items either in the jewelry section or in discount bins.

The items were then tested by Weidenhamer. Of 61 samples, 59 contained at least 5 percent cadmium by weight, with 53 of those registering 10 percent or higher.

Weidenhamer’s prior research has shown that the testing method he used — an X-ray gun that can roughly tell the amount of cadmium in an item — typically underestimates how much is present.

Representatives of the jewelry industry have argued that the presence of cadmium, even at high levels, is not by itself proof that an item is dangerous. The important thing, they say, is how much can escape if the item is sucked, bitten or swallowed.

Lab testing conducted by Weidenhamer at AP’s request showed that several items easily shed the metal when exposed to a mixture that simulated human stomach acid.

The day after AP’s original report, Walmart said it was pulling two of the highlighted items: pendants with themes from the Disney movie “The Princess and the Frog.” Within three weeks, the chain had agreed to recall all the pendants already sold.

Since then, federal regulators have issued two more recalls, for charm bracelets sold at the international jewelry chain Claire’s and at a Dollar N More store.

While AP’s January investigation focused on jewelry clearly intended for children, the items tested for AP this time were labeled “not intended for children under 14 years.” That is an important legal distinction: Under current law, children’s items are defined as for kids 12 and under, and children’s products are subject to regulations that others are not.

For reasons that are not fully understood, girls ages 6 to 11 — a range that includes many fans of Cyrus’ “Hannah Montana” TV show, movies and CDs — appear to be more at risk from cadmium.