Sandy, The concentration of mercury in the Hepatitis B vaccine was 25,000 parts per billion ppb mercury.
This was injected into newborns only in the United States. This level of mercury is 125 times higher than what the EPA classifies as hazardous waste. Children received 3 of these plus 8 vaccines that contained 50,000 ppb Hg in the 1990s. Aluminum is a catalyst for mercury and makes it much more toxic.
Mercury from other sources are negligible compared to the injection of high doses of organic mercury into babies and pregnant women. This is not safe!