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USP 232/233 Elemental Impurities FAQs: Part 1

FDA requires compliance to USP 232/233

The United States Pharmacopeia (USP) <232> and <233> chapters specify the limits and procedures for the screening and quantification of potentially toxic metal impurities. Elemental impurities don’t provide any therapeutic benefits, and their levels in a drug product should be controlled within the acceptable limits set forth in FDA guidance. The guidance applies to both new finished drug products (as defined in ICH Q6A and ICH Q6B) and new drug products that contain existing drug substances. Contaminants, impurities, and residuals in biopharmaceutical products can delay the launch of a product when items fail to comply with regulations, including those set forth in USP 232 & 233.

In this 2-part blog series, we’ll be answering your most frequently asked questions about elemental impurities testing.

Has your elemental analysis group seen any samples from pharmaceutical companies that are above the limits set in FDA guidance?

We do not often analyze pharmaceutical products which contain high levels of heavy metals of concern. This is likely due to the fact that suppliers of API and excipients are well aware of the stringent controls needed to produce a high-quality product conforming to the USP and ICH metals limits.

How long does USP 232/233 metals testing take and what is your lead time?

We can perform full USP <232>/<233> testing on your pharmaceutical product in about 25 business days. This time frame includes method development, validation, and testing of various lots. Our typical lead times are less than a week.

Do you have a specific project in mind? Talk to a scientist.

Does Avomeen have experience in testing nutritional supplements and OTC products for elemental impurities?

Yes, Avomeen has performed metals testing for a multitude of raw materials and finished products across all pharmaceutical and over-the-counter products.

What instrumentation is used for USP 232/233 testing?

We utilize two Agilent ICP-MS systems. Our primary instrument is the new Agilent 7800, and as a back-up, we have the 7500.

What certifications does Avomeen hold? Have you been inspected?

Avomeen is a cGMP-compliant, DEA-registered, and FDA-inspected laboratory. We have recently undergone a successful Pre-Approval Inspection by the FDA, and our elemental analysis group who conducted USP 232/233 testing for our client with respect to their ANDA submission performed exceptionally. We also hold ISO 17025 accreditation.

Additional Resources

Check it out the second installment in this blog series for answers to the most frequently asked technical questions. Do you have more questions for our elemental analysis team? Let’s talk.

Interested in knowing more about elemental impurities testing? Check out our blog and infographic for a look inside our typical elemental impurities testing timeline, in accordance with USP 232/233 guidelines.



Our featured blogger is Mike Lindenmuth, Avomeen’s Director of Business Development for the Mid-Atlantic and Southeast regions. Mike has been involved in the pharmaceutical industry for nearly 20 years, from working in drug discovery to serving in technical sales and business development roles for organizations supporting pharmaceutical research and development.