A method to identify the presence of heavy metals in pharmaceuticals was introduced in the United States Pharmacopoeia more than 100 years ago. Today, pharmaceutical companies are still using essentially the same method, the USP <231> Heavy Metals Limit Test. Daniel Morland of Butterworth Laboratories gives an overview of the current method limitations, considerations for the new methodology, and the risk-based assessments being carried out by manufacturers.
https://international-pharma.com/wp-content/uploads/2014/03/Elemental-impurity…pdf.pdf