Yes, we should remove lead pipes, but clean drinking water is still no guarantee

A proposed new rule from the Environmental Protection Agency (EPA) would mean that most cities have to replace their lead water pipes within a decade. That’s a big deal—but it doesn’t actually go far enough to end the problem of lead in water, because lead is present in indoor plumbing, too. Even if you live in a city that has already replaced old service lines, you should probably be using a water filter.

“We know that the majority of homes, if not all, have lead-bearing plumbing,” says Yanna Lambrinidou, cofounder of the nonprofit Campaign for Lead Free Water and an affiliate professor in the department of science and technology at Virginia Tech. “And we know from the science that as long as you have lead-bearing plumbing, you are at risk of exposure.” Lead is unsafe at any level of exposure and accumulates in the body; higher levels can lead to brain damage in children and heart disease in adults.

If pipes and fixtures in your house corrode, lead can end up in your water. It’s invisible and tasteless, so you won’t know that it’s there. Even testing your water can’t accurately assess the risk—the water might be fine at the moment you test but contaminated shortly afterward because lead releases into water erratically.

“It’s a little bit like a Russian roulette phenomenon—there is an inherent and dramatic variability in lead release,” says Lambrinidou. “Using a one-time test to assess whether a tap dispenses contaminated water is not appropriate.” In one study, researchers found that in cases with extreme variability, you’d need to take more than 1,200 samples from a tap to get a clear understanding of the lead contamination.

Although homes, schools, and other buildings built after 1986 were required to use “lead-free” pipes and solder, the EPA’s definition even allows for small amounts of lead in those materials. So it’s not possible to find truly lead-free fittings: When Lambrinidou worked on a remodeling project in her own house, she wasn’t able to find any manufacturers who could guarantee that their products had zero lead. It’s safest, she says, is to use a water filter.

Both Michigan and Washington, D.C., now have “filter first” policies that require schools and daycare centers to install filters at every tap that’s used for drinking or cooking. The same thing makes sense in homes. (Filters need to be certified for lead and either installed at a tap or used in a pitcher; “whole-house” filters installed in a basement aren’t a good solution because they aren’t filtering lead from pipes or faucets inside the house.)

Though filters are effective, they’re also not a complete solution since some people may not be able to afford them and they have to be changed regularly to work correctly. Lead plumbing also needs to be replaced in old homes and apartment buildings. Removing old lead-service lines—the pipes that connect city water mains to individual homes—is especially important because they’re made from 100% lead, and if something goes wrong in a city’s water treatment, reactions in the pipes can cause lead levels to spike. But it’s important for people to understand that there’s still a risk after lead service lines are swapped out, and it will take even longer to address the challenges inside houses.

That message isn’t always clear. The EPA’s press release about its plan to remove lead pipes, for example, included a quote that suggested the new rule would mean “we will never again see the preventable tragedy of a city, or a child, poisoned by their pipes.” But even cities that don’t have lead service lines, like Portland, Oregon, still routinely exceed what the EPA considers safe levels of lead, Lambrinidou says.

“Public education is really critical for ensuring that communities are aware of what the risk is and what steps they can take to prevent exposure,” she says.