That’s what makes the disaster in Ohio so frightening. Five rail cars of vinyl chloride—some of it intentionally made to reduce construction pressure—burned dioxins that could be producing toxic compounds. Because hot air rises from a fire, the flames from the train sent black plumes high into the air, potentially spreading toxins far beyond the track’s location. “The thing about dioxins is that they’re potent at very low levels, and they’re persistent and bioaccumulative,” Schettler says. This means they stay in the body rather than breaking down. “You don’t want to deposit dioxins in the soil around East Palestine that won’t go away, and are going to bioaccumulate in people who are exposed to it.”
The Environmental Protection Agency has deemed the air in East Palestine to be safe. Officials also said the water is safe to drink. But there are still many unknowns about these individual chemicals and the way they mix together and burn, according to Gerald Markowitz, an occupational and environmental health historian at the City University of New York. “There is real concern that there is no safe level of exposure to carcinogens,” says Markowitz.
Being so toxic, what was vinyl chloride doing on a train? PVC is one of the most common types of plastic, used especially in pipes, but also in packaging and consumer products such as shower curtains. There are about 5,000 businesses in the United States alone that produce the various types of plastic, says Judith Enck, president of Beyond Plastics and former EPA regional administrator. And they all need ingredients. “It’s not just trains, but also trucks that move the stuff,” says Enck.
And it’s not just vinyl chloride. Manufacturers must add other chemicals to give plastics their plastic properties – things that make the polymer more heat resistant, for example, or more flexible. Many of these are known endocrine disrupting chemicals, or EDCs, which cause our hormones to go haywire. That’s why bisphenol A, aka BPA, was mentioned after scientists linked it to cancer, behavioral conditions and diabetes.
But it’s a whack-a-mole game. When one chemical is found to be dangerous, manufacturers substitute another chemical that may be just as, if not less, toxic. “Research hasn’t been done to find out if they’re safe, or if they’re that dangerous, but they’re still a concern,” says Markowitz. It will likely take years before we know the potential side effects of replacement chemicals, he says.
And BPA was just any of the other 2,400 chemicals in plastics that scientists consider to be of concern. A 2021 study found that exposure to plastic chemicals called phthalates could be responsible for 100,000 premature deaths in the US each year – and that was a conservative estimate.
The main issue is that what is put in plastic does not stay in plastic. When a bag or bottle breaks apart, it releases its chemical constituents as leachates. Heat and freezing also split any plastic into microplastics, which pollute every corner of the environment, as well as our own bodies. They have been found in human lung tissue, intestines, blood, and even the first feces of a newborn. But we know very little about the health consequences of microplastics, although early studies have found that microplastics are highly toxic to human cells in laboratory experiments. The fire in East Palestine is a frightening example of a crisis that is getting worse by the day.