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This substitute for lead pipes could carry its own risks

  • 26 November 2024
  • ckearns

Many industry and water officials argue plastic pipes pose no health risks, while some advocacy groups are raising the alarm.

By Amudalat Ajasa

Updated November 20, 2024 at 11:07 a.m. EST | Published November 20, 2024 at 7:00 a.m. EST

As water utilities mobilize to replace millions of lead pipes across the country, they are sometimes choosing plastic, which some advocates worry can pose its own risks to drinking water.

Last month, the Biden administration finalized a landmark rule requiring the removal of all lead pipes within a decade, a decision that has renewed awareness of materials often used in their place. One common substitute is polyvinyl chloride, which is made from the chemical vinyl chloride, a known human carcinogen.

There is an ongoing debate about the amount of vinyl chloride that’s in PVC pipes and whether the substance can leach into drinking water. Many industry and water officials argue plastic pipes pose no health risks. Yet, environmental advocates are sounding the alarm about the threat of exposure through drinking water. They point to instances such as the 2023 train derailment in East Palestine, Ohio, which spotlighted the threat of vinyl chloride when massive plumes of the chemical were sent into the air. Vinyl chloride has been linked with liver, brain, lung and breast cancer, and other health problems.

“Communities that are installing PVC pipes are going to be right back where they were with lead pipes in toxicity,” said Judith Enck, who heads the advocacy group Beyond Plastics and whose organization called PVC pipes a “regrettable substitution” for lead ones in a 2023 report. “Let’s not relive the whole saga with what we’ve seen with lead pipes.”

The push to eradicate lead pipes gained steam after the water crisis in Flint, Michigan, raised concerns about the country’s aging water infrastructure about a decade ago. Since then, the federal government has grappled with ways to address the danger that lead pipes pose to the country’s drinking water.

The White House estimates that more than 9 million homes across the country are still supplied by lead pipelines, which are the leading source of lead contamination through drinking water. In some places, lead service line replacements have been ongoing for years. The Environmental Protection Agency has not provided any guidance to local municipalities about what to replace lead pipes with, giving them the autonomy to decide themselves. In addition to PVC, copper and stainless steel are also common materials used to replace lead pipes.

A plastic alternative to lead piping
According to the PVC Pipe Association, a trade group, more than 40,000 water utilities across the country use PVC pipes and more than 1 million miles are in service. They make up about 78 percent of all new drinking water distribution pipes installed in North America.

Last December, the EPA launched a formal evaluation of the risks of vinyl chloride under the Toxic Substances Control Act. At the time, the EPA said it would study whether the chemical poses an “unreasonable risk to human health or the environment.”

In the coming weeks, the EPA will determine whether designate vinyl chloride as a risk under the law, EPA spokesman Remmington Belford said. If vinyl chloride is designated a “high-priority substance,” the agency would identify how the chemical can be used and ways in which people are exposed to it at high levels, which could include drinking water.

Vinyl chloride is normally used in polyvinyl chloride products — plastic materials including pipes, cable coatings and packaging materials. PVC has become a popular piping alternative because it’s cheaper and is thought to be more durable than metal pipes that can corrode with time. Lead pipes, for example, can corrode and leach lead into drinking water.

But the chemical composition of PVC pipes gives some experts pause. A report last year from Beyond Plastics cited research that found up to 50 chemicals were released into the water by PVC pipes and other plastic fittings.

Do chemicals seep out of PVC pipes?
Martin Wagner, a toxicologist and biologist who has studied PVC materials, said it is well known that chemicals leach from plastics.

“These chemicals do not stay in the plastic. They don’t stay in the PVC, and they can easily leach into water,” said Wagner, who is a professor in Norwegian University of Science and Technology’s department of biology. Wagner — who has studied the way chemicals leach from consumer products — hasn’t specifically studied PVC piping, but he said based on other PVC products he has studied, he believes many chemicals can leach from pipes, too. For example, one study he worked on found a single PVC product can contain between 800 to 9,000 chemicals. His studies of PVC materials found that between 400 to 5,000 chemicals transferred into water from their original product. He added that leaching is especially high in new pipes because levels of chemicals are much higher in newer tubes than in older ones.

Chris DeArmitt, founder of the Plastics Research Council, dismissed claims about PVC leaching chemicals into drinking water by Beyond Plastics and other environmental groups, citing safety tests by the National Sanitation Foundation, an independent third-party organization.

The EPA relies on standards set by NSF to establish limits on how much chemical contaminants can be introduced into drinking water.

DeArmitt, who has a PhD in chemistry, said vinyl chloride gas is used during the manufacturing process of plastic pipes and only “incredibly small amounts are left after you make the pipe.”

Enck, who was an EPA regional administrator during the Obama administration, questioned the validity of NSF standards, stating the organization is partially funded by the pipe manufacturers who pay the organization to certify their products.

NSF explained that it tests products to determine if it meets certain standards, and that certification program is funded by a fee for the testing. It said those payments — and the individual manufacturers or parties whose substance is being tested — have no influence on the decision.

While it’s unclear how much chemical leaching occurs through PVC pipes, low doses can be harmful and may increase the risk of liver cancer. According to the EPA, drinking water with 2 parts per billion of vinyl chloride over a lifetime corresponds to an excess lifetime cancer risk of 1 in 10,000.

Some argue PVC pipes pose no health risk to people and are a viable replacement for lead pipes. Alan Roberson, the executive director of Association of State Drinking Water Administrators, said that PVC is an inert material, which means different conditions and chemicals won’t cause vinyl chloride to leach out.

“The bottom line here is that I don’t think this is a significant issue as a large percentage of water mains across the country are made of PVC,” Roberson said.

He said his confidence in PVC safety is driven by leach testing done by the NSF.

Still, PVC pipes have been rejected by some water utilities because of uncertainties about durability and risks to health.

It took the city of Newark less than three years to replace almost 24,000 lead pipes, according to Newark Water & Sewer officials. The city’s efforts have been praised by the Biden administration.

Newark officials said they did not use PVC pipes because of studies from the 1980s in which residents complained about water taste. Instead, the city opted to use copper pipes.

Newark Water & Sewer Director Kareem Adeem said he believes that the city made the right choice.

“We didn’t want to abate one crisis and start another one for generations down the line,” Adeem said.

Article Source: https://www.washingtonpost.com/climate-environment/2024/11/20/lead-pipe-plastic-pvc-replacements-risks/

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