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Are adjuvants and preservatives in vaccines safe?

The Claim:

A prolific Twitter account is claiming that no studies showing aluminum adjuvants (per a FOIA) or thimerosal to be safe exist and that a secret CDC meeting proves that the government is trying to keep this secret from us.

The Facts:

Most of these claims are based on conspiracy theories featuring Simpsonwood and FOIA requests. Let’s take those first before handling the science.

The 2000 Simpsonwood CDC conference was a two-day meeting organized by the CDC to discuss data from the Vaccine Safety Datalink regarding the possible link between the mercury compound thimerosal in vaccines and neurological issues in vaccinated children. Attendees included experts in various fields, public health organizations, and pharmaceutical companies. The conference gained notoriety in the anti-vaccination movement when RFK Jr. wrote an article in 2005 alleging a conspiracy to withhold vaccine safety information. However, the article contained numerous factual errors, leading to its retraction.

In 2007, the Senate HELP Committee reviewed the allegations against the CDC and found they had mostly no merit. It was found that the CDC did not interfere with vaccine safety studies, and the review groups did not rely on manipulated studies. However, four other allegations were not substantiated, including claims that the CDC convened the Simpsonwood Conference to cover up findings, pressured Dr. Thomas Verstraeten to change his findings, hid the Vaccine Safety Datalink, or organized public health organizations to hide a link between vaccines and autism. And we know that vaccines do not cause autism.

Most vaccines are for single use, meaning one vial equals one dose for one person. However, a few vaccines are multi-dose and require preservatives to prevent contamination. Thimerosal, a mercury compound used today in some flu vaccines, has caused concern due to its name being confused with a harmful type of mercury. Thimerosal contains ethylmercury, which is safe and quickly leaves the body. It’s different from harmful methylmercury found in some fish. Thimerosal has been used safely in vaccines, drugs, and contact solutions since the 1930s. Nowadays, most vaccines use single-use vials, and thimerosal-free vaccines are available for those still concerned.

As for the aluminum FOIA requests, the Freedom of Information Act (FOIA) is meant to access government records, not to ask agencies questions or investigate scientific matters. The fact that lawyers keep using FOIA for such purposes implies that they might be aware of this but are being misleading or dishonest. This misleading tactic can be effective, which is why it’s important to set the record straight.

Adjuvants aid your immune response for better protection against diseases. They’ve been used in vaccines since the 1930s, and millions of American children have safely received them. Adjuvants, like aluminum, are found naturally in foods. The amount in vaccines is safe, with infants getting less aluminum from vaccines in six months than from breast milk in the same time. Vaccines with adjuvants are rigorously tested for safety and monitored by health authorities like the CDC and FDA.

Disclaimer: Science is always evolving and our understanding of these topics may have evolved since this was originally posted. Browse the latest information posted in Just the Facts Topics.

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