In short, yes. In 1979, the U.S. Food and Drug Administration ruled that bottled water could contain no more than 2 parts per billion (2 micrograms per liter) of mercury. This is identical to the standard set for public drinking water by the U.S. Environmental Protection Agency.
So what makes mercury so dangerous in your water supply? And how does it get there?
Mercury contamination is a worldwide problem. It can come from many sources. It occurs naturally in the environment in rocks, soils, water, and air. Products containing mercury that are thrown in the garbage or washed down sinks and drains end up in landfills, incinerators, or sewage treatment facilities. Mercury from these products can leach into the ground and groundwater. Mercury may be directly released into the environment, or through combustion (burning) activities, from coal-fired power plants, where it is released in fine particles in the air that fall to the earth in rain or snow.
Once released into the environment, mercury eventually ends up in the water and settles into sediments. Bacteria in the water convert the inorganic mercury into methyl mercury, an organic mercury compound. In 1974, the Safe Drinking Water Act made the Environmental Protection Agency responsible for ensuring the safety of municipal water systems, which includes setting maximum limits for chemical, bacteriological and radioactive contaminants and physical contaminants that affect odor, taste, and color. In 1986, amendments to the Safe Drinking Water Act required EPA to set additional standards. When EPA adds or amends a contaminant standard, the Food and Drug Administration must set an acceptable level for it in bottled water or publish in the Federal Register its reasons for not doing so.
Since 1975, under the "misbranded products" provision of the Federal Food, Drug, and Cosmetic Act, FDA has been responsible for ensuring that the quality standards for bottled water are compatible with EPA standards for quality and safety of tap water. In 1978, FDA broadened the bottled water standards to include maximum allowable contaminant levels for pesticides, mercury, and radioactive matter. In carrying out its mission to ensure the safety of bottled water, FDA also inspects bottled water facilities on a regular basis. Like other foods, bottled water must be processed, packaged, shipped, and stored in a safe and sanitary manner, and be truthfully and accurately labeled.
As a result of the growing demand for bottled and mineral waters, the FDA recently proposed regulations that would establish standard definitions for all bottled water products, and set new limits for approximately 50 chemicals and other contaminants that may be present in bottled water. FDA has already established quality standards for 31 contaminants. The regulations would also apply the quality standard requirements for bottled water to mineral water. IBWA petitioned FDA to establish stricter guidelines for bottled water in l988.
After studying the situation, FDA proposed standard definitions because the terms provided by the "misbranded products" provision of the Food, Drug, and Cosmetic Act were not specific enough for use in identifying components of such a diverse group of bottled water products. In the end, The FDA dealt swiftly with the bottled water industry by saying, "The bottled water industry has grown too much over the last few years to continue handling violations on a case-by-case basis," the FDA said.. "We need revised bottled water regulations that are broad-based and careful to protect our citizenry from mercury, or other contamination."