Replacing Lead Water Pipes with Plastic Could Raise New Safety Issues

A landmark federal commitment to fund the elimination of a toxic national legacy--lead drinking water pipes--promises to improve the public health outlook for millions of people.

The Bipartisan Infrastructure Law allocated fifteen billion dollars for the removal and replacement of lead service lines in the U.S. About a third of the nation's estimated 6 million to 10 million such lines could be replaced with the funds.

The Natural Resources Defense Council published a set of guiding principles for lead-line replacement after the anticipated surge of lead-pipe-replacement work. The document takes a stand against the use of plastic pipes and calls for the use of copper lines.

Many water quality and health questions about plastic drinking water pipes in the US are unresolved or have yet to be addressed by a number of experts. Some industry representatives don't agree with the findings about plastic drinking water pipes. As communities receive federal funds for replacements, they must consider the many dimensions of choosing the safest and most suitable new pipes for their region.

Various sources say that service lines are usually made of copper, iron, steel or one of several types of plastic. According to Bluefield Research, up to 35 percent of U.S. utilities spending on drinking water distribution will go towards plastic pipes in the next decade. Plastic materials are usually less expensive to purchase up front than more traditional materials. Plastic is expected to make up 80% of the nation's water pipe inventory by the year 2030.

Many medical and public health leaders agree that there is no safe level of lead exposure. Intellectual deficits, neurological and reproductive problems, and increased risk of cardiovascular death are all caused by taking in low levels of lead from paint and drinking water.

The matter of potential drinking watercontamination is less clear with plastic pipes. The copper-not-plastic item in the NRDC-led group points to recent research that suggests plastic pipes can potentially taint drinking water. Several studies have documented the release of chemicals into the water from the pipe material. Permeation involves pollutants such as gasoline that can get into the ground through the walls of plastic pipes and has been noted in reports by the Environmental Protection Agency. Plastic pipes are at risk of melting due to the high heat of the wildfires. According to the NRDC document, plastic pipes damaged in fires could release toxic chemicals into the water. The high heat of fires can degrade plastic pipes, valves and meters, potentially releasing volatile organic compounds into drinking water, according to the EPA document. The 2020 study revealed that plastic pipes exposed to wildfire temperatures can release benzene, a carcinogen, and other volatile organic compounds into the water.

There are pipe material-related factors that can affect drinking water. The growth of the Legionella pneumophila, the water-borne bacterium that causes Legionnaires' disease, varied with the water's pH, according to a July laboratory study by civil and environmental engineer.

Some organizations associated with the plastic pipes industry are not in agreement with the findings that link these pipes with potential drinking water quality and health concerns Bruce Hollands, executive director of the Uni-Bell PVC Pipe Association, points to a 2015 environmental product declaration that followed an assessment of seven PVC water and sewer pipe products by the ISO. According to the declaration,PVC pipe and fittings are resistant to chemicals found in water and sewer systems, preventing any leaching or releases to ground and surface water. Chemicals are not released into the water system. There are no known toxicity effects when using the product. The same statement will be contained in an update due out in a few months.

A similar position is held by a nonprofit organization called the National Sanitation Foundation, which is one of several organizations to offer testing that can lead to certification of manufacturers' drinking water pipes and other system components. The National Science Foundation said in a statement that they are not aware of credible evidence that would discourage the use of plastic pipes in drinking water systems.

The committee of manufacturers, toxicologists, water utilities and federal and state regulatory officials make Standard 61. The standard is recognized by two organizations, the American National Standards Institute and the Standards Council of Canada. Independent third-party testing standards for plumbing materials have been supported by the EPA. It's only a requirement for pipes to be free of lead. Standard 61 is used to certify pipes and other water distribution system products.

Consumers with questions about the safety of pipes that are in contact with drinking water should focus on individual products that are certified to appropriate standards, rather than the materials that pipes are made of, according to a statement from the National Science Foundation. There are some material related trends that have emerged.

It is extremely rare for metal pipes to be permeated. According to a Water Research Foundation report, pure benzene and other dangerous organic compounds can also be found in the pipes without the rubber gasket. The conclusions of the report were called "incoherent and possibly misleading" by the Plastics Pipe Institute.

According to a 2006 National Research Council report, all pipes can be affected by some degree. It's possible to manage copper that comes from pipes made of that metal. Studies have found that plastic pipes can release compounds that are potentially toxic. Under the Safe Drinking Water Act, state standards for contaminants must be at least as stringent as federal ones. The current questions that need to be answered are which pipe- related contaminants get into drinking water, the extent to which they might affect water quality and human health, and whether any industry-independent researchers or government regulators are looking for specific concerning contaminants at all.

Rather than advocating for one material over another, many U.S. environmental engineers say the choice of material for any given underground water pipe should depend on factors such as whether a pipe will be flushed before use.

In a 2020 study funded by the EPA, Patrick Gurian and his colleagues found statistically significant higher concentrations of total organic carbon in some PEX pipes than in copper pipes. The organic carbon in a water supply can come from decaying leaves and other natural sources.

The two individual water systems in Philadelphia and Boulder, Colo., had different characteristics due to a number of factors. Water systems have variations. Quality control measures, such as proper testing and certification, can be used to address plastic pipe's effects on the environment. Managing risks and tradeoffs is what engineering is all about. I don't know if banning all plastic from use as pipes is justified. Plastic pipe has been extensively studied for all sorts of supposed maladies since the early 1980s according to the Plastic Pipe and Fittings Association.

Plastic pipes in the U.S. don't have the same level of water quality and health scrutiny as pipes made of other materials. Andrew Whelton is an environmental engineer at Purdue University. Plastic pipes are not like that. Colleges and graduate schools that train civil engineers and public health researchers have historically ignored the chemistry and manufacturing of plastic in their curricula.

Scott Coffin, a research scientist at California's State Water Resources Control Board, studies the impacts of microplastics in drinking water on human health. There needs to be more research on water quality and plastic drinking water pipes. Coffin says that plastic pipes are not explored a lot. In the water industry, it's forgotten.

Whelton and his colleagues have been asking questions about the water carried in plastic and other types of drinking water pipes Toluene, one of 90 or so contaminants for which the EPA has set legal limits in drinking water, was found in the water that was in contact with PEX pipes. Water did not enter the building. The team published a study two years later that compared the contents of copper and plastic pipes. For the first three days of exposure, the thresholds for microbial growth were exceeded. Whelton and colleagues found that heavy metals, including copper, iron, lead and zinc, formed scales inside PEX drinking water pipes in a home's one year old plumbing system.

None of the studies funded by the U.S.'s National Science Foundation were intended to make health claims. They were supposed to show potential contaminants that could be produced by interactions between drinking water and plastic pipes.

The organization that reported $123 million in revenue in 2020 was the nonprofit testing and certifying organization. The final product complies with specific standards for safety, quality or performance if it is certified by an independent organization.

The conclusions and data from the plastic drinking water pipes study have contributed to misinformation and confusion, according to a document released by the National Science Foundation.

Each study was peer-reviewed and there was no misinformation in it. He says that the organization's document is an example of misinformation and should not be taken seriously.

When it comes to drinking water safety and plastic, the organizations that signed onto the lead-service-line-replacement principles headed by NRDC have put their trust in other areas. The NRDC-led group has a document of principles that links to studies and reports. According to the document, the Healthy Building Network, the International Association of Fire Fighters and the United Association are all in favor of copper replacements. When you have so many people, especially when they agree, shouldn't you reexamine this?