The IVS believes that it is important to share all information with parents and health care providers so that they can make the most informed choices about how to minimize mercury exposure to children. The IVS supports the use of the safest possible vaccines for children. The following supplemental information is provided by the Institute for Vaccine Safety to clarify some aspects of the new information about thimerosal and mercury in vaccines. More detailed information will be forthcoming within the next few weeks from a variety of sources.
Thimerosal is a mercury-containing preservative that has been used in some vaccines for many years.
The AAP will provide more information in the forthcoming guidelines. These guidelines were written with the assumption that children will be exposed to low levels of mercury over a long period of time so that the concentration in the body builds up to steady-state level over time. The agencies responsible for the guidelines need to independently determine if the exposures from vaccines exceed this level and how these exposures should be counted. At this time the IVS is not aware of any evidence that the amount of thimerosal in the vaccines has caused any harm except for mild allergic reactions. Nevertheless, we should reduce any potential risk however small.