Tom Neltner, J.D., is Chemicals Policy Director
Communities around the country are testing their water for lead. But when they get the results, parents, public health officials, housing agencies and school officials have little guidance about what the number means and what actions to take or priorities to set. For lead in dust and soil in homes, child-care and schools, they have health-based numbers that serve as benchmarks for assessing risk. There is no such benchmark for drinking water. As a result, many are using the “Lead Action Level” of 15 parts per billion (ppb) as a surrogate. Yet, this level is based on the effectiveness of corrosion control; it has no relation to the associated health risks of lead exposure.
Yesterday, the Environmental Protection Agency (EPA) helped fill the void by releasing a draft report that provides three different approaches to setting a scientifically-robust “health-based benchmark” for lead in drinking water. The agency is seeking public comment on the draft and will convene a panel of scientific experts to consider each of the approaches.
The report is a critical step in implementing the recommendations of the agency’s National Drinking Water Advisory Council (NDWAC) which called for this type of health-based benchmark as part of an overhaul of the Lead and Copper Rule. The agency went a step further and provides alternatives to consider. We applaud EPA for its action and its rigorous, scientific analysis.
Accounting for the various models and assumptions, EPA developed a range of potential health-based benchmarks that range from 3 to 56 ppb of lead in water that people actually drink. However, you cannot readily compare these values to the typical water testing results reported by utilities or schools. Those tests are based on the first draw of water that has been sitting in the faucet and plumbing overnight and do not necessarily reflect what people drink over the course of a day. Later samples would likely be lower but could be higher if the building has a lead service line, especially if the line has been disturbed. Read More