LEAD IN DRINKING WATER

Following the water crisis in Flint, Michigan, many water consumers are asking the common question: is my drinking water safe? Everyone is exposed to background levels of lead, given its widespread distribution: soil, paint chips, dust, and drinking water. The amount of lead in drinking water is generally fairly low and also highly regulated. Lead enters drinking water primarily as a result of corrosion, or the wearing away, of materials containing lead. For example, lead service lines, lead solder used to join copper piping, and household plumbing and fixtures. 

Regulatory measures taken during the last three decades have worked to greatly reduce human exposure to lead in drinking water: 

  1. Safe Drinking Water Act
  2. Lead and Copper Rule
  3. Lead Free Law

The Safe Drinking Water Act (SDWA) is the federal law that ensures safe, public drinking water supplies throughout the nation. Prior to the SDWA, there were few enforceable requirements for drinking water; however, the improvements in the technology of sampling and testing allowed for contaminants to be identified at smaller concentrations and subsequently regulated. The Safe Water Drinking Act was passed in 1974 and clearly identified the roles of the EPA, at the federal and state levels, as well as the responsibilities of water operators at the local level. 

In 1986, the Safe Water Drinking Act saw its first set of amendments which included the regulation of many known contaminants, as well as, the banned use of lead pipes and lead solders in drinking water distribution systems and new residential and commercial construction. 

Legacy lead pipe sections, including lead service lines, still represent the greatest potential source of lead in drinking water systems. The estimate on the number of full or partial lead service lines that remain in the United States varies largely. Some surveys have returned estimates ranging from 6 million to as many as 10 million lead service lines.

Residential Sources of Lead Exposure

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