The 1999 thimerosal decision: when federal agencies first acted on mercury in vaccines
Why it matters
Reform advocates point to 1999 as the moment the government itself conceded there was a mercury-exposure problem worth acting on, the historical foundation of the modern causation argument.
In 1999, the FDA determined that cumulative mercury exposure from thimerosal-containing childhood vaccines could exceed federal safety guidelines for infants. In July 1999, the American Academy of Pediatrics and the U.S. Public Health Service issued a joint statement recommending thimerosal be removed from vaccines as a precaution.
In 2000, the CDC convened the Simpsonwood conference to review Vaccine Safety Datalink data on possible links between thimerosal and neurodevelopmental disorders, a meeting that reform advocates, including Robert F. Kennedy Jr. in his later writing, have cited as pivotal.
Mainstream science holds that subsequent research found no association between thimerosal and autism. That 1999–2000 record is where this story really starts: the documented moment federal agencies acted first and argued the science afterward.
Source
AJF reporting.
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