Cheap sewer pipe repairs can push toxic fumes into homes and schools – here’s how to lower the risk – Planet Detroit

Andrew J. Whelton, Purdue University

Across the United States, children and adults are increasingly exposed to harmful chemicals whose source few people know.

It begins on a street in front of a house or school, where a worker is repairing a sewer pipe in a manhole. The craftsman inserts a resin-soaked sleeve into the buried pipe and then heats it, turning the resin into a hard plastic pipe.

This is one of the cheapest and most common methods of pipe repair, but it carries a serious risk: heating the resin creates harmful fumes that can travel through the sewer lines into surrounding buildings, sometimes several blocks away.

These chemicals have sickened hundreds of people, forced building evacuations and even led to hospitalizations. Playgrounds, daycare centers and schools have been affected in several states, including Colorado, Connecticut, Massachusetts, Michigan, Pennsylvania, Washington and Wisconsin.

This method of sewer pipe repair involves blowing chemical waste into the air and allowing it to enter buildings through buried sewer pipes, wires, cracks in the foundation, windows, doors, and heating, ventilation, and air conditioning units.
Andrew Whelton/Purdue University

As the bipartisan Infrastructure Act of 2022 now directs hundreds of millions of dollars to communities across the U.S. to fix broken pipes, the number of children and adults at risk of infection is likely to rise.

For more than a decade, my colleagues and I have worked to understand and reduce the risks of this innovative pipe repair technique. In two new studies in the Journal of Environmental Health and Environmental Science and Technology Letters, we show that workers and even bystanders, including children, are not adequately protected.

Our research also shows that the technology can be used safely if companies take appropriate measures.

Repairing old pipes with harmful chemicals

As the U.S. water infrastructure ages, communities across the country are grappling with thousands of broken sewer pipes in their 1.3 million-mile sewer system.

The new law provides $11 billion for sewer repairs, about a fifth of what the EPA estimates will be needed.

The blue cured-in-place pipe (CIPP) is seen in this damaged storm sewer pipe. The CIPP was made by steam baking the resin into the hard plastic.
Andrew Whelton/Purdue University

The most cost-effective repair method is called the cured-in-place pipe (CIPP) method. This method does not require digging up and replacing pipes. Instead, contractors insert a resin-soaked sleeve into the shaft and through the buried pipe. The resin is then “cooked,” usually with steam or hot water, and turned into a hard plastic.

One challenge is that not all chemicals are listed in the resins' safety data sheets, and some completely new ones are created when heated.

The chemical fumes rising from nearby manholes and exhaust pipes are not just “steam” either. These fumes contain highly concentrated chemical mixtures, uncooked resin, particles and nanoplastics that can harm human health. When we studied the heating process in the laboratory, we found that up to 9% of the resin was released into the air.

CIPP production has been shown to release about 40 chemicals. Some cause nausea, headaches, and eye and nose irritation. They can also cause vomiting, difficulty breathing, and other effects.

During the manufacturing of CIPP systems, waste containing chemicals, uncooked resin, particulates, and nanoplastics is released into the air. These complex emissions are not water vapor. Andrew Whelton/Purdue University.

Styrene, the most commonly documented chemical, is highly toxic and “reasonably likely” to be carcinogenic, according to the National Research Council. Chemicals other than styrene may also be responsible for the toxicity of the plumes.

CIPP-associated diseases in neighboring buildings

So far, chemical exposure has been reported in at least 32 states and seven countries. In addition to schools, this process has also contaminated homes, restaurants, medical facilities and other businesses. Companies have been sued for exposing their workers to dangerous levels of styrene.

The first known incident in the United States occurred in 1993 at an animal shelter in Austin, Texas. Seven people were overcome by the fumes and taken to a hospital. In 2001, fumes entered a hospital in Tampa, Florida, causing respiratory problems among staff. Since then, hundreds more people have been known to have been exposed to the fumes, and the number is likely much higher.

In our experience, exposures are rarely made public. Municipalities have asked people affected by fumes to contact the CIPP contractor and the pipe owner only. In some cases, people have been told that exposures are always harmless.

Chemicals can enter buildings through sinks, toilets, cracks in the foundation, doors, windows, and heating and ventilation systems. The chemicals can even enter buildings that have water-filled traps. In anticipation of this risk, passersby were instructed to cover their toilets and close all windows and doors.

Wind can help reduce chemical concentrations outdoors. However, concentrated plumes can travel through buried pipes into nearby buildings. Bathroom fans can sometimes increase chemical concentrations indoors. Concentrations have been found in buried pipes that should prompt firefighters to wear respirators.

Fumes created during sewer repairs (right) can enter nearby homes, schools and other buildings.
Andrew Whelton/Purdue University

The highest values ​​were observed during and after the heating process.

Portable air testing devices commonly used by firefighters and contractors cannot accurately detect certain chemical levels. A previous study showed that styrene levels were sometimes thousands of times off.

How to protect public health

With the wave of infrastructure projects looming, it is clear that controls are needed to reduce the risk of people being harmed.

Our research highlights several actions that citizens, businesses and health authorities can take to ensure safety in their communities.

We advise residents:

• Close all windows and doors, fill siphons with water and leave the building during pipe curing work, especially if there are children in the building.

• Report unusual odors or illness to health authorities or call 911. Seek medical advice from health authorities, not contractors or pipe owners. Evacuate buildings if fumes enter.

Companies can also minimize risks. They can:

• Stop cooking when fumes leave the work area to reduce the spread of contamination and exposure.

• Use resins that cause less air pollution than standard resins.

• Ask federal agencies to evaluate the use of portable air testing devices.

• Capture and treat air pollution from the process. While this has not yet been done on a large scale, it is straightforward and would only be a fraction of the total project cost. This waste is hazardous due to its toxicity.

Health and environmental agencies should also get involved. Federal agencies know that this practice poses health risks and can be fatal to workers. California and Florida note in safety documents that bystanders could be harmed. But so far few steps have been taken to protect the health of workers and bystanders.

Andrew J. Whelton, Professor of Civil, Environmental and Ecological Engineering, Director of the Healthy Plumbing Consortium and the Center for Plumbing Safety, Purdue University

This article is republished from The Conversation under a Creative Commons license. Read the original article.