12/12/2025
There’s been a lot of discussion about mercury in vaccines, so here’s some helpful perspective based on public health data.
In the past, many vaccines contained thimerosal, a preservative that breaks down into ethylmercury. A single dose includes about 25 micrograms(µg) of mercury, roughly the same amount found in a 3-ounce can of tuna or an 8oz cut of commercial fish. Ethylmercury is cleared from the body quickly, while the methylmercury found in fish builds up over time.
For comparison, an average an 8-ounce serving of commercial fish contains about 23 µg of methylmercury. Even an exclusively breast-fed infant will naturally ingest more total mercury from breast milk in the first six months of life than was ever contained in childhood vaccines prior to 2001.
As of 2001, no childhood vaccines contain thimerosal.
Currently, only a very few adult vaccines contain thimerosal. All of these are multi-dose vials. These are very rare and are being phased out. If there is any question(even though there is no legit risk), a single dose vaccine will not contain thimerosal.
It’s important to understand that the forms of mercury, how the body processes them, and how exposure limits are set are all different. Clear information helps us keep vaccines in perspective and focus on keeping families healthy. Do not fall for click bait and conspiracy. Follow the science...not the hysteria.