Mercury is a real public health concern. You may have heard scientists warning against eating too much salmon or other fish because of the way it concentrates heavy metals, so why is mercury found in the vaccines we give our kids? More importantly, why are scientists trying to stop the total ban of mercury?
The World Health Organization are trying to see mercury phased out (it’s found in many household items). However, the WHO want to ban a product called thiomersal. This is a mercury compound added to vaccines that extend it’s shelf life. In the US and Canada, thiomersal has mostly been removed from childhood vaccines.
A ban on mercury would be devastating to pharmaceutical companies and would mean preservative-free vaccines with shorter shelf-life and higher costs. This would be a big problem for third world country vaccination programs.