Lead to Plastic: Are We Trading One Hazard for Another?
Dangerous, outdated lead service lines have got to go. We must not waste this generational investment and place New York’s drinking water at risk of new contamination by replacing lead with plastic pipes.
By Valerie Baron, National Policy Director & Senior Attorney, Safe Water Initiative, Environmental Health. Coauthored with Elin Betanzo, president and founder, Safe Water Engineering, and Eve Gartner, director, crosscutting toxics strategies, Earthjustice.
Originally published at NRDC.org.
Plastic pipes are not proven safe, and we have good reason to question their safety. The strongest and most immediate concern is microplastics and toxic chemicals being released from the plastic into tap water, but those in the know in the industry also question how long plastic pipes will really last.
Plastic pipes haven’t been around long enough for us to know as much about them as we know about other materials. But the science suggests that the materials comprising the plastic pipes—the plastic polymers, fillers, and contaminants that are frequently present—do get from pipes into drinking glasses. In other uses, exposure can cause serious associated health effects, and there is no evidence that it’s any safer in pipes. Although sometimes people notice a “plasticky” taste or odor to tap water from plastic pipes, many plastic contaminants cannot be tasted or smelled. There is also good reason to question how durable plastic pipes are and how long they will last in the real world, not a computer model.
Top concern: Microplastics and chemicals could contaminate tap water
Plastic service lines shed microplastics and allow toxic chemicals to leach into drinking water.
There are no federal Safe Drinking Water Act requirements to test tap water for plasticizers or plastic degradation products like microplastics.
Utilities test water for the vast majority of contaminants at treatment plants, not at household taps where people actually drink the water.
There is no standard that adequately evaluates plastics, fillers, or additives and their cumulative effects under real household conditions.
As a result, whereas lead and copper are tested at the tap, we do not know how much plastic contamination residents are exposed to through plastic water mains and service lines.
The “50-year lifespan” claim is not proven
Industry’s claims that PEX (cross-linked polyethylene) pipes last 50 years are based on laboratory modeling and extrapolation, not real-world service line data.
PEX was not approved for water service in plumbing codes until 1997, making a verified 50-year lifespan impossible to confirm.
A recent American Water Works Association (AWWA) journal article presents findings that copper has a lower failure rate than a variety of plastics.
Even AWWA acknowledges that lifespan claims rely on simulations (“extrapolation” of “hydrostatic strength”) rather than observed performance.
AWWA’s key PEX report is weak evidence
The AWWA Committee Report that’s frequently cited to support PEX was published in 2012 and was not peer-reviewed.
Many claims rely on outdated test conditions or lack citations altogether.
Assertions about durability, freeze resistance, and erosion are based on assumptions rather than field data.
NSF/ANSI Standard 61 does not prove safety
NSF/ANSI Standard 61, a general water materials standard that some have inappropriately touted as the imprimatur of safety for materials, has minimal testing requirements and does not quantify exposure at the tap. It is not a proxy for supplying safe drinking water.
Confirming that a plastic pipe is NSF/ANSI Standard 61–certified is difficult. There is no one-stop shop to identify certified materials when selecting pipes for drinking water applications.
NSF/ANSI Standard 61, sometimes touted as proof that plastic pipes are safe, relies on testing methods that do not reflect actual household exposure at the tap, that do not measure microplastics, and that require the testing of very few product samples. These sample requirements are not sufficient to show real‑world quality variation between or within product batches.
Further, compliance with NSF/ANSI Standard 61 is not mandated by federal law, though it is often incorporated into state requirements.
In contrast, there are already requirements for copper sampling at customer taps, and compliance data dating back to the 1990s is available for water utilities across the country.
Peer-reviewed science raises red flags
Peer-reviewed research, including multiple studies by Purdue University researchers, documents chemical leaching, degradation of PEX, and impacts on water odor and quality.
These findings directly contradict industry assurances that PEX is inert and stable.
Durability and cost risks
New AWWA-published data shows copper service lines have lower failure rates than plastic alternatives. Copper service lines have lower failure rates than plastic alternatives.
Recent lawsuits allege some PEX products failed within a few years, despite expectations of decades-long performance.
Material costs are a small fraction of total replacement costs; choosing a weaker material risks another generation of costly replacements.
Bottom line
PEX service lines are not proven safe, lack real-world longevity data, and present unresolved public health risks—especially from microplastics. Copper remains the best-supported, most durable, and most health-protective option for service line replacement.