The world's largest retailer learned in February that the items are tainted, but has continued selling them.
The AP also found that a separate line of jewelry charms being sold at Wal-Mart also had high cadmium levels.
Long-term exposure to cadmium can lead to bone softening and kidney failure.
Representatives for both Wal-Mart and Miley Cyrus have not responded to repeated requests for comment.
Last month, Wal-Mart revealed its suppliers now have to prove that children's jewelry and other kids' products have little cadmium. But that policy didn't apply to items already on store shelves.
