On Feb. 3, 2023, a Norfolk Southern freight train transporting hazardous material derailed in East Palestine, Ohio, releasing toxic chemicals such as vinyl chloride into the environment and threatening the long-term health of the local community.
Yale School of Public Health Professor Vasilis Vasiliou, chair of the YSPH Department of Environmental Health Sciences and director of Yale’s Superfund Research Center, recently discussed the derailment and chemical spill and what public health officials can and should do to address the situation.
What can public health officials do to help the East Palestine community return to normal after a serious incident such as this?
V.V.: It is an enormous challenge and one made worse by the fact that evidence shows the incident involves not just five chemicals as stated by EPA but potentially many more, including those that can form from the incomplete combustion of a mixture of chemicals and materials. The purposeful detonation of tanker cars containing unburned chemicals may have been a safety measure, but it put considerably more chemicals and particulates in the air. The liquid spill, and perhaps even some airborne combustion products, can contaminate soil, waterways, and eventually groundwater. And there is the potential for chemical residues to be present in homes, and on cars, decks, and playground equipment.
What do you think of the emergency response so far?
V.V.: From the reports, it appears that many of the response actions have been protective: evacuation of people in harm's way, proactive provision of bottled water to those on private wells, and testing of air, soil, and water. However certain decisions, like the detonation of the tanker cars mentioned above, and the decision to allow people to return to their homes after five days of offsite shelter without waiting for comprehensive testing and cleanup, have led to questions and concerns.
What steps would you recommend public health officials take to address this situation?
V.V.: Health and environmental authorities must take the following steps to ensure residents’ health is protected and to restore residents’ confidence that their community is safe:
1. Thorough testing and cleanup
The startling array of chemicals involved in the release was:
- Vinyl chloride (a known human carcinogen)
- Butyl acrylate (an eye, skin, and respiratory irritant)
- Ethylhexyl acrylate (an eye, skin, and respiratory irritant)
- Ethylene glycol monobutyl ether (an irritant, central nervous system depressant, and possible reproductive toxicant and carcinogen)
- Tsobutylene (a liquid fuel similar to propane)
2. Identify all chemical threats
Additional chemicals of concern include potentially 10s to 100s of chemical byproducts produced by the fire including powerful irritant gases such as hydrogen chloride and phosgene and chemicals that are worrisome due to their long-term toxicity and biomagnification such as dioxins. These latter chemicals are produced in fires involving organic matter and chlorine; we can’t rule out the possibility that dioxins were generated in this chemical fire without proof from appropriate sampling data.
3. More testing
As homes are cleared based on air testing for vapor-phase chemicals like vinyl chloride, phosgene, and hydrogen chloride, testing of deposited soot, house dust, and soil needs to be comprehensive, looking for chemicals that can be long-term hazards such as dioxins and polycyclic aromatic hydrocarbons. One literature source shows that 3-6% of a vinyl chloride fire is incompletely combusted soot. The level of soot can be higher in a complex multi-component and variable temperature fire such as that which occurred in Ohio. The chemicals in that soot need to be characterized.
Cleanup procedures should specifically target chemicals found in soot, house dust, and outdoor soil. These contaminants should be professionally cleaned from homes and the local environment. While the rail company is being held responsible for this cleanup, oversight agencies need to make sure that the cleanup is thorough and gets contaminant levels back to background levels.
5. Medical evaluations
There is an array of underlying medical conditions that can be worsened by smoke inhalation and chemical exposure as well as the stress of this situation. Environmental medicine experts should be on the scene assisting local physicians and alerting them to the potential for increases in asthma, inflammatory, autoimmune, and cardiopulmonary disorders as well as irritations of the eyes and skin. Surveillance of the community for hospital visits and admissions will help determine the true health impact of this exposure.
6. Follow-up groundwater monitoring
Chemicals spilled or fallen out onto the soil do not immediately reach groundwater. Depending upon the amount of local rainfall and depth to the groundwater, contamination could take several years. While private well testing is taking place, it will be more important to do so on a seasonal basis (two to four times a year) for the next five years.
7. Risk communication
There is good reason for the level of alarm that is evident in the community. It is vital that there be transparency with respect to what has been tested, what those results show, what measures are being taken to return the homes, yards, streets, soils, and waterways to normal conditions, and how public health will be surveilled going forward.
8. Improved safety precautions
The trail derailment was not a freak accident of nature like a tornado, just a routine transport that literally went “off the rails”. Whether it was a wheel bearing failure as has been speculated or some other initiating event, the NTSB (National Transportation Safety Board) needs to figure out what went wrong and how to prevent it from happening again. While we can never prevent all shipping accidents, the weak links in the chain must be identified and fortified.
Featured in this article
- Vasilis Vasiliou, PhDDepartment Chair and Susan Dwight Bliss Professor of Epidemiology (Environmental Health Sciences) and of Ophthalmology and Visual Science and of Environment; Director, Yale Superfund Research Center; Affiliated Faculty, Yale Cancer Center; Affiliated Faculty, Yale Institute for Global Health