March 27, 2023
Thom Carroll/for PhillyVoice
After thousands of gallons of a latex solution spilled from a Bucks County plant and contaminated the Delaware River, three chemicals involved in the incident have been identified as butyl acrylate, ethel acrylate and methyl methacrylate.
Philadelphia officials named three chemicals that flowed into the Delaware River after a pipe burst Friday night at an industrial plant in Bucks County – butyl acrylate, ethel acrylate and methyl methacrylate.
These chemicals were part of a latex-based solution that spilled into Otter Creek, a tributary of the Delaware River, which supplies drinking water to a large portion of Philadelphia residents.
Public health officials and water treatment facilities still are working to determine the full extent of the contamination and the relative risks to people who may come in contact with these chemicals from tap water. About 8,000 to 12,000 gallons of the solution spilled into Otter Creek.
It is important to note that a range of factors may influence the potential level of hazard to the public, including the characteristics of the spill, the routes of exposure and the risk mitigation taken in response to it.
"There is a lot of conflicting information out there. We're trying to do that concrete information gathering so we can really assess and make sure that we're giving good information about what are the potential ramifications," said Maya van Rossum, leader of the Delaware Riverkeeper Network, an environmental advocacy group that works throughout the Delaware River Watershed.
In the days since the spill from the Trinseo Altuglas plant in Bristol, the company has described the latex solution as a blend of approximately 50% water and 50% latex polymer. The company said the pigmentation of the solution initially made it visible on the surface of Otter Creek and later the Delaware River.
Philadelphia officials have advised that tap water sourced from the Delaware River remains safe to consume until the end of the night on Monday. Trinseo did not respond to a request for more information about the spilled chemicals after being contacted Monday morning.
Below is a look at each of the chemicals identified in the spill and the known health risks associated with exposure to them.
Butyl acrylate is a clear, colorless, flammable liquid that's used in the manufacture of polymers, resins, sealants and paint formulations.
The chemical is an irritant of the eyes and skin, as well as the mucous membranes of the nose, throat and respiratory tract, according to the CDC.
Acute exposure to butyl acrylate in its raw form can cause redness, tearing and irritation of the eyes. Inhalation can cause runny nose, scratchy throat, dizziness, nausea and difficulty breathing. Repeated chronic exposure to the skin can cause redness, swelling, itching and and cracking. Chronic exposure may also result in damage to the lungs and nervous system, with possible behavioral effects.
Butyl acrylate was among the chemicals released in the train derailment and explosion in East Palestine, Ohio in February.
The federal limit for butyl acrylate in drinking water is 560 parts per billion. As contaminated water moved down the Ohio River following the derailment, health officials repeatedly tested water samples downstream and reported that butyl acrylate was present at less than three parts per billion — well below the federal threshold.
Ethyl acrylate is a colorless liquid with a sharp odor that's detectable to the human nose at levels far below what would be considered harmful to people. The chemical compound is used in the production of acrylic resins, water-based latex paints, plastics, rubber and materials used by dentists.
The CDC says ethyl acrylate can affect the body if it is inhaled, comes in contact with the eyes or skin or if it is swallowed. Short-term exposure may cause irritation to the eyes, nose, throat and lungs. Breathing it at high levels in the air can cause serious complications. The compound is considered a potential carcinogen in humans since it has been shown to cause stomach cancer in animals.
Since the primary route of human exposure to ethyl acrylate is through inhalation, research on the effects of ingesting it in drinking water is limited.
Methyl methacrylate is a colorless, flammable liquid with a sharp, fruity odor. It is slightly soluble and floats on water. It's used to make plastics, resins, paints, coatings and dental materials.
Like the chemicals above, methyl methacrylate can affect the body if it comes into contact with the skin and eyes, or if it is swallowed.
Short-term exposure to the methyl methacrylate can cause irritation of the nose, throat and eyes. It may also cause drowsiness, neurological symptoms or unconsciousness at very high levels, according to the CDC. Prolonged, chronic exposure can lead to skin rashes, respiratory and cardiovascular impairment and potential liver damage through oral exposure based on findings in animals, according to the U.S. Environmental Protection Agency.
Research on the effects of ingesting methyl methacrylate in contaminated drinking water is limited.
The city provided a map showing which areas are served by the Baxter Water Treatment Plant, which is the Philadelphia water facility most impacted by the downstream path of the spill. Its intakes were shut off before any contaminated water reached the plant.
The Philadelphia Water Department is maintaining minimum levels of water at the Baxter facility in order to continue supplying water for the fire department and other needs. A water distribution plan is being developed, if needed, to manage the Baxter plant and supply the public with safe water until the contamination risk has passed.
Since the spill, PWD has analyzed a mix of samples from the river and raw water basin. No contaminants related to the Bristol Township spill had been found in PWD's water system as of Monday afternoon. If that changes, the public will be notified immediately, officials said.
City officials advised impacted residents to fill bottles and pitchers with tap water to ensure they had enough water, should contaminants eventually appear in the city's water supply.
Van Rossum said there are a number of outstanding questions about the circumstances of the spill and what has transpired since then.
"We don't have information about what was happening with the tide at the time this was released, which could have significant implications. We don't really have solid information about how much was recovered and where it was recovered from, or how much is in the system and where it's expected to be located," van Rossum said. "We need to know what sampling is being done by whom and for what. We're getting reports about chemicals — but who's testing the water, and are they testing for those chemicals or some sort of byproduct?"
She stressed that these basic issues should be addressed with the public in a more dynamic way, including press conferences and Zoom meetings where people can get their questions answered in real-time.
"The lack of information is concerning and leaves all of us in a quandary about what's happening. It shouldn't be that way," she said.
