In January 2001, the Environmental Protection Agency (EPA) lowered the Maximum Contaminant Level (MCL) for arsenic from 50 parts per billion (ppb) to 10 ppb. The lower federal standard becomes effective in January 2006 for existing Group A Community (serving more than 25 people) and non-transient, non-community (NTNC) public water systems.
As a result of lowering the MCL, arsenic reporting requirements for the annual Consumer Confidence Reports (CCR) were changed. Depending upon the level of arsenic detected, community water systems must include the concentration of arsenic reported by the laboratory and possibly an educational or health effects information statement about arsenic in their CCRs.
CCR reporting requirements depend upon the concentration of arsenic reports by a laboratory. Arsenic concentrations within the three ranges described below have distinct reporting requirements. If a laboratory reports an arsenic value of "
Arsenic reported below 5 ppb:
Any arsenic value reported by a laboratory above the method detection limit and below 5 ppb must be included in the CCR water quality data table. There are no additional reporting requirements for results below 5 ppb.
Arsenic reported between 5-10 ppb: (use EPA's or DOH's suggested language below)
EPA's educational statement - in federal rule:
While your drinking water meets EPA's standard for arsenic, it does contain low levels of arsenic. EPA's standard balances the current understanding of arsenic's possible health effects against the costs of removing arsenic from drinking water. EPA continues to research the health effects of low levels of arsenic, which is a mineral known to cause cancer in humans at high concentrations and is linked to other health effects such as skin damage and circulatory problems:
Department of Health's recommended educational statement:
Your drinking water currently meets EPA's revised drinking water standard for arsenic. However, it does contain low levels of arsenic. There is a small chance that some people who drink water containing low levels of arsenic for many years could develop circulatory disease, cancer, or other health problems. Most types of cancer and circulatory diseases are due to factors other than exposure to arsenic. EPA's standard balances the current understanding of arsenic's health effects against the costs of removing arsenic from drinking water.
Arsenic reported above 10 ppb:
EPA's health effects statement - in federal rule:
Some people who drink water that contains arsenic in excess of the MCL over many years could experience skin damage or problems with their circulatory system, and may have an increased risk of getting cancer.
For questions about the Consumer Confidence Report regulation, contact your Drinking Water Regional Office:
Northwest Region, Kent: 253-395-6750
Southwest Region, Olympia: 360-236-3030
Eastern Region, Spokane: 509-329-2100