Cal/EPA’s Office of Environmental Health Hazard Assessment (OEHHA) has proposed a new public health goal for perchlorate in drinking water that would lower the current 6 parts per billion (ppb) goal to 1 ppb.

Perchlorate, a chemical used in air bags, rocket fuel, military munitions, fireworks, and other explosives, has leached into groundwater supplies in California and other states, resulting in expensive environmental cleanups.

The proposal cites studies indicating that perchlorate can interfere with the thyroid’s ability to absorb iodine and disrupt it from producing hormones that regulate metabolism. It also cites studies about the chemical’s potential to affect the health of infants. OEHHA will accept comments until February 23, 2011.