Nickel, lead and other metal limit tests have started disappearing from some pharmacopoeial monographs over the past few years. As in the European Pharmacopeia monographs for Mannitol and Erythritol.
This does not mean that analysis of these metals is no longer needed!
There is a requirement for elemental impurities to be assessed in all materials in accordance with European Pharmacopeia chapter 5.20 and United States Pharmacopeia chapter <232>, this covers a total of 24 elements including nickel and lead. This requirement followed the removal of the Heavy Metals limit test some years ago.
Where a monograph contains a metal limit test that overlaps with the Elemental Impurities you can expect that test to be removed in a future versions.
Elemental impurities testing can be challenging with requirements for low limits of detection in sometimes tricky sample matrixes. Butterworth laboratories have extensive experience with elemental impurities testing and offer a material specific validation service should it be required.