Thimerosal (Mercury) Law
Thimerosal, a chemical used to prevent contamination of multi-dose vials of vaccines, contains mercury. California’s Mercury-Free Act took effect on July 1, 2006. The Act prohibits administering mercury-containing vaccines to pregnant women or to children younger than three years of age. To meet the “mercury-free” standards in this law, most vaccines may not have more than 0.5 micrograms of mercury per 0.5 milliliters of vaccine dose. The mercury limit for influenza vaccine is 1 microgram per 0.5 milliliters. All routine vaccines are available in formulations that meet the Mercury-Free Act.
Exemption for the use of seasonal influenza vaccine in children younger than 3 years of age and pregnant women through June 30, 2013:
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