Addressing parents' concerns: do vaccines contain harmful preservatives, adjuvants, additives, or residuals?

Pediatrics. 2003 Dec;112(6 Pt 1):1394-7. doi: 10.1542/peds.112.6.1394.


Vaccines often contain preservatives, adjuvants, additives, or manufacturing residuals in addition to pathogen-specific immunogens. Some parents, alerted by stories in the news media or information contained on the World Wide Web, are concerned that some of the substances contained in vaccines might harm their children. We reviewed data on thimerosal, aluminum, gelatin, human serum albumin, formaldehyde, antibiotics, egg proteins, and yeast proteins. Both gelatin and egg proteins are contained in vaccines in quantities sufficient to induce rare instances of severe, immediate-type hypersensitivity reactions. However, quantities of mercury, aluminum, formaldehyde, human serum albumin, antibiotics, and yeast proteins in vaccines have not been found to be harmful in humans or experimental animals.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adjuvants, Pharmaceutic / adverse effects
  • Adjuvants, Pharmaceutic / standards
  • Animals
  • Biological Products / adverse effects
  • Biological Products / chemistry
  • Biological Products / standards
  • Drug Contamination
  • Drug Storage
  • Humans
  • Pharmaceutic Aids / adverse effects*
  • Pharmaceutic Aids / standards*
  • Preservatives, Pharmaceutical / adverse effects
  • Preservatives, Pharmaceutical / standards
  • Risk
  • Vaccines / adverse effects*
  • Vaccines / chemistry
  • Vaccines / standards*


  • Adjuvants, Pharmaceutic
  • Biological Products
  • Pharmaceutic Aids
  • Preservatives, Pharmaceutical
  • Vaccines