California dentists have agreed to adhere to state Proposition 65 and warn patients that mercury can “cause birth defects or other reproductive harm.” This follows a December $350,000 settlement with the San Francisco-based environmental group As You Sow.
The 18,000 members of the California Dental Association can still use mercury in amalgam fillings.
Beside the low-level health risk from inhaling mercury vapors or swallowing worn-away particles, the mercury in fillings can threaten ecosystems, according to state and federal studies. Discarded with pulled teeth, left in cadavers, ingested, or washed down the drain in minute amounts, amalgam mercury often gets incinerated, vaporizing and falling out into watersheds. There, it methylates, drastically increasing its danger to ecosystems. Mercury fillings are 25% cheaper than the next cheapest option.
According to surveys by the US Bureau of Mines/US Geologic Survey and Chemical Engineering News, dentists nationwide use an average of 40 tons of mercury annually. “Mercury is being phased out in every kind of product,” said As You Sow’s Larry Fahn. “But the [dental industry] is very reluctant to change.”
Abandoned mines are the largest source of the mercury in the San Francisco Bay. According to a 1997 US EPA report, coal-fired power plants are the largest source of atmospheric mercury emissions nation-wide, releasing about 50 tons annually.
“The amount of mercury that gets methylated in the environment from the dental industry is probably much less than that from power generation,” said Davis Baltz of Health Care Without Harm, “They don’t allow it in thermometers, thermostats, but the fact is, the dental industry has been in denial that mercury is a problem.”
HR 4163, introduced in the California Assembly in April, 2002 would phase out mercury fillings by 2007.