Pharmaceutical Research

, Volume 27, Issue 5, pp 750–755 | Cite as

Metal Impurities in Food and Drugs

  • Darrell R. Abernethy
  • Anthony J. DeStefano
  • Todd L. Cecil
  • Kahkashan Zaidi
  • Roger L. Williams
  • USP Metal Impurities Advisory Panel


The major metals of potential health concern found in food, drugs (medicines), and dietary supplements are lead, cadmium, mercury, and arsenic. Other metals, such as chromium, copper, manganese, molybdenum, vanadium, nickel, osmium, rhodium, ruthenium, iridium, palladium, and platinum, may be used or introduced during manufacturing and may be controlled in the final article as impurities. Screening for metals in medicines and dietary supplements rarely indicates the presence of toxic metal impurities at levels of concern. The setting of heavy metal limits is appropriate for medicines and is appropriate for supplements when heavy metals are likely or certain to contaminate a given product. Setting reasonable health-based limits for some of these metals is challenging because of their ubiquity in the environment, limitations of current analytical procedures, and other factors. Taken together, compendial tests for metals in food and drugs present an array of issues that challenge compendial scientists.


analysis impurities limits metals standards US Pharmacopeia 



Agency for Toxic Substances and Disease Registry


Centers for Disease Control and Prevention


Current Good Manufacturing Practices


Environmental Protection Agency


Food and Drug Administration


Graphite Furnace Atomic Absorption Spectroscopy


International Agency for Research on Cancer


Inductively Coupled Plasma–Optical Emission Spectroscopy


Inductively Coupled Plasma–Mass Spectroscopy


International Program on Chemical Safety


Integrated Risk Information System


Joint Expert Committee on Food Additives


Lowest Observed Adverse Effect Level


Minimal Risk Level


Not Applicable


Not Determined


No Observed Adverse Effect Level


Office of Environmental Health Hazard Assessment


Permissible Daily Exposure


Reference Dose


US Pharmacopeial Convention


World Health Organization



The authors thank Stefan Schuber, Ph.D., ELS, director of scientific reports at USP, for editorial assistance.


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Darrell R. Abernethy
    • 1
  • Anthony J. DeStefano
    • 1
  • Todd L. Cecil
    • 1
  • Kahkashan Zaidi
    • 1
  • Roger L. Williams
    • 2
  • USP Metal Impurities Advisory Panel
  1. 1.Documentary Standards DivisionUS PharmacopeiaRockvilleUSA
  2. 2.Chief Executive OfficerUS PharmacopeiaRockvilleUSA

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