The fiasco in Flint, MI has forced an important change in EPA’s recommended protocols for testing lead in drinking water. In a memo to state health and water administrators issued February 29, 2016, the US EPA reversed its prior recommendations on how to sample drinking water targeted for lead testing. The new protocols are as follows:
- Do not remove or clean faucet aerators prior to collecting samples
- Do not pre-flush prior to sampling
- Use wide mouth sample bottles to allow water flow to enter at a rate similar to what consumers might use when pouring a glass of water to drink
In the past, EPA‘s advice was to pre-clean the aerator, flush pipes prior to sampling, and open the tap slowly and sample at low flow. Using these guidelines results in less particulate lead getting into the sample and thus finding lower lead concentrations in the water. Removing or cleaning an aerator prior to testing masks the added contribution of lead at the tap that results from the lead in the aerator. Flushing the pipe prior to sampling eliminates the lead that has built up overnight or since the last time the faucet was used. Pouring the water slowly, whether by using a narrow container or by just opening the tap slowly, also reduces particulate lead that gets into the water by not disturbing lead present in the pipe as much as a normal flush would. These inaccurate procedures were called to task by Dr. Marc Edwards from Virginia Tech University who found high levels of lead in the drinking water in Flint, MI.
Despite the fact that this is not what people typically do when they pour a glass of water from the sink to drink, these are the sampling procedures that EPA has been advocating for years and what water companies have been using for years to measure lead in drinking water. By using these procedures, water companies everywhere, not just in Flint, are not accurately measuring the lead concentration in drinking water, and they are potentially missing a significant portion of the lead actually in the drinking water systems. Doing this provides a false sense of security that seriously endangers public health.
Although EPA has issued these new guidelines, there’s no guarantee that water companies around the country have switched to the new sampling procedures. If you’re concerned about the lead levels in your water, find out what sampling procedures are being used because it makes a huge difference. While we can thank the public attention given to the disaster in Flint for this critically important change, now we need to make sure that testing agencies across the country follow this new protocol. Contact CHEJ at info@chej.org to obtain a copy of this important memo.
