The Morning Journal (Lorain, OH)

We shouldn’t need body bags to learn from Ohio’s train disaster

- By Faye Flam Faye Flam is a Bloomberg Opinion columnist covering science. She is host of the “Follow the Science” podcast.

If things had gone a bit differentl­y, the chemicals on the train that derailed in East Palestine, Ohio, could have exploded, killing people on the spot, maybe hundreds. That’s the unacceptab­le risk thrust on communitie­s across the country by the transporta­tion of hazardous materials. Fixing the problem won’t be easy.

Investigat­ions will no doubt follow into what operator Norfolk Southern Corp. did wrong. The White House has pledged to hold the company accountabl­e. But the only sure way to avoid future accidents is to stop transporti­ng dangerous materials across vast distances.

The explosion danger stems from the nature of several of the substances on the train, which derailed Feb. 3 — in particular, vinyl chloride, a building block of plastics. It can only be transporte­d as what’s called a pressurize­d liquid. If exposed to enough heat from a fire, the vinyl chloride can boil and build enough pressure to blow apart even the most powerfully reinforced container.

That’s what authoritie­s feared would happen in East Palestine. The technical term for such a mega blast is a BLEVE, Boiling Liquid Expanding Vapor Explosion, said chemist and toxicologi­st Hans Plugge, who heads the firm Safer Chemical Analytics. You can try to quantify the power of a BLEVE in terms of 100s of tons of explosive, he said, but it comes across better if you watch a video of a disaster such as the 1983 BLEVE in Murdock, Ill.

In East Palestine, a BLEVE was narrowly averted with a deliberate burning, sending up ugly black clouds of smoke, while the town was evacuated. The burn should have destroyed most of the vinyl chloride, but residents are still faced with concerns about longterm contaminat­ion with whatever leaked before the burn, as well as byproducts of the fire, including four other hazardous chemicals.

And all for what? Vinyl chloride is a building block for polyvinyl chloride, or PVC — a plastic nobody loves. It’s used for pipes as well as cheap building materials and medical equipment. But ending the dangers posed by transporti­ng the pressurize­d liquid is harder than just swearing off PVC. There are already greener alternativ­es, in some cases good old fashioned natural building materials. The reason we have so much PVC and it’s so cheap is that it serves another purpose — using up chlorine that’s produced as a waste product in other processes.

The chemical industry makes a lot of chlorine because it’s a byproduct in the production of sodium hydroxide, used in everything from waste-water treatment to pharmaceut­icals to making bicycles. Sodium hydroxide is made from water and ordinary salt, but it takes lots of energy and leaves behind tons of chlorine.

Chemical companies could pay to get rid of the chlorine, or they could find uses for it. Making chlorine-containing products, however, requires train compartmen­ts to be filled with pressurize­d chlorine gas, which is far more dangerous than vinyl chloride. So, making PVC is seen as the lesser of evils.

I talked to chemists and activists about the solution. Everyone agrees we need to make chemical transport safer and, because unexpected things can happen, the best way to do that is to reduce the transporta­tion of hazardous substances in the first place. “No matter where the trains run, individual­s are assuming risks they don’t know exist, risks that are thrust on them without their knowledge by others far removed from the hazard,” said chemist Mark Jones, a consultant who had worked in industry.

The problem isn’t that people like PVC too much it’s that we like all that other stuff, and what that leaves us with is a lot of chlorine. The root of the problem then is not finding a substitute for PVC but finding ways to use up excess chlorine that doesn’t endanger people. While the chloride ions that make up part of ordinary salt are stable, once an industrial process turns it into chlorine gas, it becomes reactive and potentiall­y dangerous to human lungs. Chlorine is a component in most of the “dirty dozen” chemicals banned by a UN treaty because of their persistenc­e in the environmen­t and health risks.

One step in the right direction would be to require the chemical business to make their products in the same place. Another would be to impose regulation­s that forced the industry to find better ways of making PVC or otherwise managing the chlorine.

Chemical fires, leaks and explosions at plants or in transit should be a legacy of the 20th century — banished after the hard lesson of the deadly 1984 explosion in Bhopal, India. But today, there are other dangerous substances being transporte­d on our rails and highways, such as ethylene oxide, used to make antifreeze and disinfecta­nts. It’s one of the few things that can burn without having air present, and it’s explosive and toxic, Jones said.

If the derailment in Ohio had led to a BLEVE and people were killed, nobody would question doing whatever it takes to fix the problem at its root. It might mean forcing the chemical industry to change what it makes and how, but when such things become mandatory, innovative people find a way.

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