Since 2001, with the exception of some influenza (flu) vaccines, thimerosal is not used as a preservative in routinely recommended childhood vaccines.
Thimerosal is a mercury-containing preservative used in some vaccines and other products since the 1930's. There is no convincing evidence of harm caused by the low doses of thimerosal in vaccines, except for minor reactions like redness and swelling at the injection site. However, in July 1999, the Public Health Service agencies, the American Academy of Pediatrics, and vaccine manufacturers agreed that thimerosal should be reduced or eliminated in vaccines as a precautionary measure.
Vaccines and Thimerosal
- CDC Study on "Prenatal and Infant Exposure to Thimerosal from Vaccines and Immunoglobins and Risk of Autism" (2010)
- CDC Study on "Infant and Environmental Exposures to Thimerosal and Neuropsychological Outcomes at Ages 7 to 10 Years" (2007)
- CDC Studies on Vaccines and Autism [PDF - 316 KB]
- Frequently Asked Questions about Thimerosal
- Timeline: Thimerosal in Vaccines (1999-2010)
Centers for Disease Control and Prevention. Recommendations regarding the use of vaccines that contain thimerosal as a preservative. MMWR 1999:48(43);996-998.
McMahon AW, Iskander JK, Haber P, Braun MM, Ball R. Inactivated influenza vaccine (IIV) in children < 2 years of age: Examination of selected adverse events reported to the Vaccine Adverse Event Reporting System (VAERS) after thimerosal-free or thimerosal-containing vaccine. Vaccine 2008;26(3):427–429.
Thompson WW, Price C, Goodson B, Shay DK, Benson P, Hinrichsen VL, Lewis E, Eriksen E, Ray P, Marcy SM, Dunn J, Jackson LA, Lieu TA, Black S, Stewart G, Weintraub ES, Davis RL, DeStefano F; Vaccine Safety Datalink Team. Early thimerosal exposure and neuropsychological outcomes at 7 to 10 years. New England Journal of Medicine 2007;357(13):1281–1292.