CDC Raises Alarm Over Thimerosal in Vaccines
On June 24, 2025, a CDC advisory group voted against the continued use of thimerosal in vaccines. The panel called the additive “a known neurotoxin” and advised removing it from vaccine formulations. This move marks a shift, as the CDC questions thimerosal for its potential risks despite past safety reviews.
Thimerosal is a mercury-based preservative. It’s used to keep vaccines safe from contamination, especially in multi-dose vials. The substance contains ethylmercury, a form that breaks down quickly in the body. However, concerns remain about its impact on health, particularly in unborn children.
Health experts say high mercury levels can affect the nervous, digestive, and immune systems. It may also pose risks to kidneys, skin, and eyes. Although removed from most childhood vaccines in 2001, thimerosal still appears in some flu shots.
Debunking Autism Claims and Study Controversy
Much of the controversy started when a now-debunked study falsely linked thimerosal to autism. Since then, dozens of studies have proven there’s no connection between thimerosal and neurodevelopmental issues. Experts like Dr. Monica Gandhi stress that this myth continues despite clear scientific findings.
The CDC panel recently cited another flawed reference that claimed thimerosal harmed animals. That study, however, was found to be fake and was quickly removed. The World Health Organization still considers thimerosal safe, based on years of evidence.
Could a Ban on Thimerosal Hurt Vaccine Access?
While the CDC questions thimerosal, experts warn a full ban could backfire. Removing thimerosal would affect flu vaccine production, especially multi-dose formats. This could result in fewer doses during peak seasons, putting more people at risk, especially children.
According to Dr. Gandhi, banning thimerosal isn’t supported by science and could reduce vaccine availability. Flu cases are already rising, while vaccination rates in children are dropping. Limiting access now could worsen public health outcomes.
