03-08-2025
Health Secretary RFK Jr. overrules scientists, bans Thimerosal vaccine preservative tied to autism claims
Reuters
RFK Jr. bans mercury-based preservative thimerosal from all US vaccines, sparking backlash from scientists and global health officials
US Health and Human Services Secretary Robert F. Kennedy Jr. has officially banned the use of thimerosal, a mercury-based preservative, from all vaccines distributed in the United States, despite overwhelming scientific evidence showing it poses no harm.
The move follows a recommendation made in June by a newly restructured vaccine advisory panel, which Kennedy controversially restaffed with ideological allies, including vocal figures from the anti-vaccine movement.
'After more than two decades of delay, this action fulfills a long-overdue promise to protect our most vulnerable populations from unnecessary mercury exposure,' Kennedy said in a statement.A mercury-based preservative, most commonly thimerosal, is a compound used in some vaccines and medications to prevent bacterial and fungal contamination, especially in multi-dose vials. Thimerosal contains ethylmercury, a type of mercury that is processed quickly and excreted from the body, unlike the more toxic methylmercury found in some seafood. It has been used safely since the 1930s, but due to public concerns, despite extensive scientific studies showing no evidence of harm, it was largely removed from childhood vaccines in the US by 2001 as a precaution.
Today, it remains only in a small number of adult flu vaccines and is considered safe by major health organizations since the 1930s, thimerosal was previously found in some multi-dose influenza vaccines, accounting for about 4-5 percent of the US flu shot supply. It has long been the target of anti-vaccine campaigns, despite more than 40 studies confirming its preservative, based on ethylmercury, not to be confused with the more toxic methylmercury found in seafood, prevents bacterial contamination in vaccines stored in multi-dose vials.
Public health experts have sharply criticized the move, warning it may reduce vaccination access and reinforce discredited fears linking thimerosal to autism and developmental disorders. Those claims, repeatedly debunked, were central to Kennedy's 2015 book and his years-long activism through Children's Health Defense. Kennedy's action bypassed usual oversight mechanisms. After firing all 17 members of the CDC's Advisory Committee on Immunization Practices (ACIP), Kennedy replaced them with eight handpicked appointees, one of whom later withdrew following a conflict-of-interest review. The newly reconstituted panel voted 5-1, with one abstention, in favor of removing thimerosal following a presentation from Lyn Redwood, an anti-vaccine figure and former leader of the World Mercury makers Sanofi and CSL Seqirus confirmed they can meet supply demands with single-dose, preservative-free alternatives. HHS officials said the Vaccines for Children program will not be broader implications of Kennedy's overhaul of federal vaccine policy remain uncertain. HHS says additional recommendations from the June panel meeting are still under review.
