Chemicals from East Palestine derailment spread to 16 US states, data shows

<span>Debris from a Norfolk Southern freight train lies scattered and burning along the tracks in East Palestine, Ohio, on 4 February 2023.</span><span>Photograph: Gene J Puskar/AP</span>
Debris from a Norfolk Southern freight train lies scattered and burning along the tracks in East Palestine, Ohio, on 4 February 2023.Photograph: Gene J Puskar/AP

Chemicals released during the East Palestine train wreck fires in February 2023 in Ohio were carried across 16 US states, new research of federal precipitation and pollution data shows.

Analysis of rain and snow samples collected from northern Wisconsin to Maine to North Carolina in the weeks following the crash found the highest levels of pH and some compounds recorded over the last ten years. That includes chloride, which researchers say was largely released during a controversial controlled burn of highly toxic vinyl chloride carried by the train.

Researchers expected to find some evidence of the burn 50 miles from the site, and the high levels of contamination in the samples across the vast range that it was spread was “very surprising” said David Gay, a University of Wisconsin researcher and lead author.

“We saw the chemical signal from this fire at a lot of sites and far away,” he added. “There was more than we ever would have guessed.”

Dozens of cars on the Norfolk Southern train derailed and burned in the town of 4,700 at the edge of the Appalachian hills. The fire burned near tankers carrying vinyl chloride, and, two days later, fearing a “major explosion”, officials conducted a controlled burn of vinyl chloride as a prevention measure.

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In the immediate vicinity and in pockets throughout the city, a potent chemical odor hung in the air for weeks. The pollution also spread far and wide because the wreck’s fires burned for so long, and the controlled vinyl chloride burn was extremely hot and concentrated, Gay said. It sent a towering plume into the earth’s free troposphere, where winds often blow between 50 to 100 miles per hour.

“That can distribute pollution a long way … and it was a nasty little fire with lots of emissions,” Gay said.

Researchers looked for a range of inorganic compounds in rain and snow water samples collected at 260 sites around the nation as part of the National Atmospheric Deposition Program.

The analysis included inorganic compounds because the federal government does not check precipitation samples for organic compounds, like dioxin or PFAS, which were also likely emitted and spread far from the fire’s site.

Chloride, or chlorine, can be a potential health and environmental threat, Gay said, but the levels researchers found “wasn’t melting steel or eating paint off buildings”.

“But these concentrations were very extreme for what we usually see,” he added.

Researchers were surprised to find “exceptionally high” pH levels in the rain as far away as northern Maine. Rain at a high enough pH can burn human skin and can harm flora and fauna, though Gay said the threat is minimal because it was a short-term spike.

He theorized the train’s cargo, which included medical cotton balls, frozen vegetables, and seminola likely contributed to the high pH because it released huge volumes of calcium, potassium and magnesium. Meanwhile, firefighting foam that may have been used at the scene also could have contributed high calcium levels that pushed up pH.

Chloride and pH levels were highest in northern Pennsylvania just east of the wreck, and along the US-Canada border. Though data for Canada was not available to researchers, Gay said he is certain its precipitation was also contaminated.

There was no precipitation or measured rain in some regions to the south and west of the wreck in Kentucky, Indiana and West Virginia, but Gay said it is almost certain the pollution came down in those regions as well, but in the air instead of rain or snow.

Meanwhile, a low pressure system that moved over the region during the burn pushed the pollution across Michigan and into Wisconsin. All the Great Lakes except Lake Superior were likely impacted, Gay said.

The levels remained elevated for the first two weeks following the fire before markedly dropping the third week.

“That’s further evidence that it’s from the train wreck,” Gay said. Though the impact of organic compounds is unclear, the inorganic findings suggest “a little shock to the system, but the system should be fine”, he added.