Letter: Lead and copper rule not health-based
It is true that lead levels in the water in Flint now are the same as for other cities that are in compliance with the federal Lead and Copper Rule, but contrary to a recent editorial (“Flint water is safe but trust lacking,” Apr. 15), this does not mean that families can drink their water without fear.
The Lead and Copper Rule is a drinking water regulation designed to measure corrosion control effectiveness. A water system exceeds the lead action level for drinking water when the 90th percentile of lead samples collected exceeds 15 ppb for lead. A lead action level exceedance indicates that corrosion control is not effective for reducing lead in enough homes, and as a result additional steps are required to address lead in drinking water. The way Lead and Copper Rule compliance is calculated, 10 percent of sampled homes can have any level of lead whatsoever and the water system can still meet the lead action level.
The Lead and Copper Rule clearly states that the safe level for lead in drinking water is 0 ppb. This is called the Maximum Contaminant Level Goal for lead. Even if your water system is below the lead action level, it does not mean there is no risk of lead exposure in your home. It means that if you have sources of lead in your plumbing, current treatment is providing some control of lead release. The sampling protocol required under the federal Lead and Copper Rule does not tell you whether your water is safe to drink.
The lead service line replacement program in Flint is ongoing. Every home with a confirmed or suspected lead or galvanized service line must continue using filters to assure that lead has been removed from the water before cooking or drinking, especially in areas where lead service line replacements shake the ground on a daily basis. In addition, data collected in Flint show that many homes have detectable lead in their drinking water, including homes that do not currently have a lead service line. Lead solder and plumbing fittings and fixtures containing lead can continue to leach lead even when the lead service line is gone. Both lead service lines and household plumbing were damaged by inadequate corrosion control while Flint delivered poorly treated water from the Flint River.
Given the sustained increase in lead exposure via drinking water in Flint and the fact that lead exposure is cumulative, it is not enough to assure the residents of Flint that they are no worse off than other older cities in the United States. Flint residents now have a body burden of lead that cannot be removed, so they must remain even more vigilant about their future lead exposure than those who have not been drinking the water in Flint. The two most effective strategies for this are using lead removing filters or bottled water.
founder, Safe Water Engineering LLC