In the aftermath of researchers finding dangerous lead levels in tap water for hundreds of homes in Flint, MI, communities around the country have been taking a harder look at their pipes, the lead within them and the well-known toxic effects of lead—developmental delays, organ damage, and even death.

In an attempt to make pipes safer, Berkeley Water Center affiliate and Civil and Environmental Engineering Professor Ashok Gadgil took on the project with his graduate student, Gabriel Lobo. They are working on a new technology that uses electrical current to rapidly build a protective layer on the insides of the pipes.

In early tests, they reduced the amount of toxic metal entering water, however other scientists are skeptical of the method’s potential as a long-term solution.

As background for how lead ended up in Flint’s tap water, researchers think the corrosive Flint River water, without the protective influence of phosphates, may have eaten away the scale on local lead pipes—and that pieces of the broken-down scale, along with newly exposed lead metal, then polluted Flint’s drinking water. A 2016 study from the National Resource Defense Council indicates 17 million people around the United States now face a similar risk.

Protective scale can be rebuilt by adding phosphates to the water, but the buildup process can take months or years. Gadgil and Lobo, however, say they have found a way to do it in a matter of hours.

Their method involves running electricity through a wire exposed to the phosphate-treated water within a pipe, and also through the pipe itself, giving the pipe a positive charge and the wire a negative one.

This makes the pipe rapidly shed positively charged lead ions into the water, where they react with negatively charged phosphate ions to form lead-phosphate scale. As a result, scale accumulates on the pipe wall much more quickly than it would under normal circumstances.

Read more Zapping Lead Pipes with Electricity Could Make Them Safer for Drinking Water at Scientific American. See Gabbriel Lobo's inteview: https://www.youtube.com/watch?v=EXjnepPVVs4&feature=youtu.be. See the official press release in Science Daily and the article To seal off dangerous lead pipes, just add electricity in Science Magazine.