Drinking water health advisory program.

The US Environmental Protection Agency prepares Health Advisories (HA) for drinking water contaminants. The HA provide technical guidance to public health officials or other interested groups on many aspects concerning drinking water contamination. The HA contain information on the chemistry, health effects, analytical methods and treatment technologies for specific contaminants. In addition, the HA include a risk assessment section which provides concentrations of the contaminant in drinking water that are not anticipated to cause adverse, noncancer health effects for 1 or 10 days or for longer exposures. Because the HA include risk assessments for less than lifetime exposures, they are useful when accidental spills occur or when regulatory limits are temporarily exceeded. The guidance documents are updated when new information becomes available that would change the previous conclusions.