A chemical leak at the Dow Chemical Co. Bayport plant on Wednesday forced officials in the town of La Porte to evacuate the surrounding area, when a the overpressurized tank vented a harmful chemical called hydroxyethyl acrylate, or HEA, into the air.

To learn more about the chemical involved in the leak – and the chemicals in the trucks and surrounding facilities – Kyra Buckley, energy reporter from Houston Public Media, spoke with the chemical engineering professor and director of Energy from the University of Houston, Ramanan Krishnamoorti.

This interview has been edited for length and clarity.

What can you tell me about hydroxyethyl acrylate, or HEA? What is the concern in the community?

So mainly, in large amount, it can impact people’s breathing, it might irritate the eyes. But the long-term challenges, such as carcinogenic or toxicological impacts, are far less than those of other types of organic molecules. Fortunately, this is something that has a high degree of attraction to water, so it tends to wash away relatively easily compared to many other organic compounds.

We understand that they found the leak in a tanker truck, and they are monitoring to see if the temperature is rising or falling in that truck. Why is this important?

When this material begins to come together, these reactions are highly exothermic – they release a lot of heat. If this process starts and progresses, then you can have an explosive reaction, and this thing can react violently and explode.

The truck from which the leak originated is parked next to two other tankers. One contains the same chemical. The other, we understand, contains a chemical called methyl methacrylate. Can you tell me more about this and if there are any concerns about this chemical compound?

It is a compound that is used in plexiglass. This tends to be, again, something that will irritate people’s eyes, it can affect your airways – but clearly no significant toxic, toxicological, or carcinogenic impacts. Like HEA, methyl methacrylate has the same tendency to create an explosive reaction. If it is extremely hot inside the tanker (over 200 degrees) this could be a challenge. But under most normal conditions, this is unlikely to be a problem. They should try to find ways to get the other trucks out of the way because once you have an explosion things are out of control and you don’t know where you are going to have the next challenge.

What questions would you ask yourself if you had to sit down with a Dow manager?

To try to understand what was the root cause of this accident. What measures can you put in place to prevent such leaks from recurring in the future? And how do you manage inventory? Is it a good idea to have these multiple trucks of the same compound nearby?

Is this type of chemical leak common?

The safety record of the industry – and indeed the country as a whole – the safety of the chemicals transported has improved. But I think 20-30 years ago these things happened a lot more frequently, so things have definitely improved. But we have to find better ways to deal with this, because at the end of the day, every time one of these leaks occurs, there is less and less confidence in the industry’s ability to handle what it is. done and manage the challenges of moving very dangerous materials across the country.