About 50 cars on a Norfolk Southern Railroad train, including 10 carrying hazardous materials, derailed in East Palestine, Ohio, on February 3, according to the U.S. National Transportation Safety Board.
The train had been carrying chemicals and combustible materials. For days, large plumes of smoke containing vinyl chloride, phosgene, hydrogen chloride and other gases were emitted during a controlled release and burn to avoid a potential explosion.
Residents from nearby neighborhoods in Ohio and Pennsylvania were evacuated because of health risks from the fumes, but have since been allowed to return, according to the AP.
A black plume and fireball rise over East Palestine as a result of a controlled detonation of a portion of the derailed Norfolk and Southern trains, Ohio, the U.S., February 6, 2023. /CFP
What are these chemicals?
Vinyl chloride, used to make the polyvinyl chloride (PVC) hard plastic resin used in a variety of plastic products, is a colorless, flammable gas that evaporates very quickly. Vinyl chloride that is released by industries or formed by the breakdown of other chlorinated chemicals can enter the air and drinking water supplies.
Phosgene is another highly toxic, colorless gas with a strong odor that can cause vomiting and breathing trouble and was used as a weapon in World War I.
Hydrogen chloride is a colorless to yellowish gas with a strong odor and its primarily effect on humans is skin, eye, nose and throat irritation.
Neil Donahue, a chemistry professor at Carnegie Mellon University in nearby Pittsburgh, said he worries that the burning could have formed dioxins, which are created from burning chlorinated carbon materials.
Threats to lives
Vinyl chloride is very toxic. Exposure to vinyl chloride may increase a person's risk of developing cancer. The inhalation of fumes of vinyl chloride could cause dizziness, nausea, headache, visual disturbances, respiratory problems and other health-related issues, Ashok Kumar, a professor in the University of Toledo's department of civil and environmental engineering, told ABC News.
EPACO workers place booms in a stream in East Palestine, Ohio, the U.S., February 9, 2023. /CFP
Environmental regulators have been monitoring the air and water in surrounding communities and have said that so far the air quality remains safe and drinking water supplies have not been affected, according to the latest report released by the U.S. Environmental Protection Agency.
But some residents have complained on social media about headaches and feeling sick since the derailment.
Taylor Holzer, owner of a dairy farm just outside the evacuation zone in East Palestine, Ohio told WKBN some foxes he keeps on his property have become mortally ill. And some have developed watery eyes and puffy faces, and have uncharacteristically refused to eat for several days, he said.
Long-term effect to local environment
Some scientists worry about the long-term dangers of the leaking chemicals to the local environment.
"Vinyl chloride has a specific and important risk in that is contains a bunch of chlorine molecules, which can form some really awful combustion byproducts," according to Richard Peltier, an associate professor of environmental health sciences at the University of Massachusetts at Amherst.
"These are often very toxic and often very persistent in the environment," Peltier said.
This photo provided by the Ohio National Guard, ONG 52nd Civil Support Team members prepare to enter an incident area to assess remaining hazards with a lightweight inflatable decontamination system (LIDS) in East Palestine, Ohio, the U.S., February 7, 2023. /CFP
According to Dana Barr, a professor of environmental health at Emory University's Rollins School of Public Health, vinyl chloride is unstable and boils and evaporates at room temperature, giving it a very short lifespan in the environment.
"But the problem they [EPA] are facing here is that it's not just a small amount, and so if they can't contain what gets into the water or what gets into the soil, they may have this continuous off-gassing of vinyl chloride that has gotten into these areas," Barr said.
"I probably would be more concerned about the chemicals in the air over the course of the next month," Barr said.
(With input from agencies, cover image via CFP)
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