Ohio Train Derailment Tells Story of Environmental Testing in an Emergency Response
What real-time air monitoring and lab analyses are being performed?
Jonathan Klane, M.S.Ed., CIH, CSP, CHMM, CIT, is senior safety editor for Lab Manager. His EHS and risk career spans more than three decades in various roles as a...
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After a Norfolk Southern train carrying industrial chemicals derailed in East Palestine, Ohio, on Feb. 3, 2023, more than 115,000 gallons of vinyl chloride leaked into the air, water, and soil. A controlled venting and burning followed to prevent the potential for an uncontrollable explosion.
An East Palestine resident who lives near the chemical-contaminated creek was told by Norfolk Southern Railroad, “Based on air testing, it’s safe to move back home.” Still concerned, she insisted on water and soil testing, too. Based on those results, a toxicologist said her house was unsafe to live in. She’s outraged and doesn’t trust Norfolk Southern.
Many others are questioning the air, water, and soil testing and whether it’s safe. Answers are often technical, vague, or unsatisfying, making it more difficult than it should be to understand. Let’s sort through what monitoring and testing are, how they differ, and what the data from this train derailment event says so far.
Monitoring versus sampling: what are the differences?
Monitoring is performed using meters and can provide useful data in real time. Sampling refers to the process of collecting samples (e.g., air, water, soil, or other) in containers or on sampling media, and sending them to a lab for various analyses.
Multi-gas meters with built-in photoionization detectors (PIDs) are the main types used for air monitoring (e.g., MultiRAE and AreaRAE). They detect oxygen levels (normal air is 20.9 percent O2), combustible gases, (i.e., the lower explosive limit or LEL), and a few specific toxic gases (e.g., carbon monoxide and hydrogen sulfide). The EPA added a detector for hydrogen cyanide and is using another gas meter (UltraRAE) configured to detect benzene.
In East Palestine, field personnel are using a PID to monitor for volatile organic compounds (VOCs). It detects VOCs with ionization potentials (IPs) less than its ultraviolet lamp’s IP (e.g., a PID with a 10.2 or higher UV bulb will detect vinyl chloride—IP is 9.99 eV). But a PID can’t tell the user which VOCs make up that total number in parts per million (ppm). Vinyl acetate (IP of 9.19 eV) and butyl acrylate (IP of 9.6 eV) are also being screened with PIDs.
Another meter being used to collect data from the site is a tape-based gas detector (Honeywell’s SPM flex) configured to detect phosgene and mineral acids (e.g., hydrogen chloride). The EPA is using a dust meter (TSI’s Dusttrax) to determine particulate matter under 2.5 microns (PM2.5) and under 10 microns (PM10) from smoke.
Monitoring is or has been done by the US EPA, Ohio EPA, Ohio’s 52nd Civil Support Team (of the National Guard), and Norfolk-Southern and/or their contractors. The latest rounds of air monitoring (done on Feb. 10 and Feb. 16-17, 2023) were normal for O2, non-detected for LEL and toxic gases, and below limits of concern for PM2.5 and PM10. PM2.5 and PM10 monitoring may have stopped due to lack of smoke.
Sampling and analysis
Air, water, and soil samples are continuing to be collected and analyzed by labs. The EPA is collecting air samples using Summa canisters (see figure 1), which collect air over time in a specific area. The air is analyzed for a large suite of VOCs such as those in analytical methods (e. g ., EPA’s TO-15).
Water samples are typically collected from various sources—surface waters (lakes, ponds, creeks, rivers, etc.), public water supplies, private wells, homes, and newly drilled environmental wells into local aquifers. The EPA detected vinyl chloride in samples from Sulphur Run, Leslie Run, Bull Creek, North Fork Little Beaver Creek, Little Beaver Creek, and the Ohio River. Ohio EPA has posted their water sample analyses here and summarized it as very low levels for earlier results and undetected for more recent results for treated drinking water (e.g., at or near the method detection limit or MDL, which is effectively zero), especially as it dilutes moving downstream in flowing creeks and rivers.
Soil samples are collected at or near the contamination and release site where it was vented and burned. The EPA criticized Norfolk Southern for not removing more contaminated soils. As a result, Norfolk Southern has committed to removing the impacted soil under the train tracks. In the future, there may be added emphasis for ongoing soil sampling, results, and actions.
Limitations and variables
Monitoring and testing are limited by several variables. First, readings are often called snapshots in time—each is a single data point. This makes it hard to generalize or extrapolate, especially about risks to the public. Second, authorities focus on legal limits set by agencies, scientific bodies, and others. They often struggle to answer concerns in layperson’s language. Plus, testing chemicals is complicated when burned—they’re a complex mix including byproducts of combustion. This can require quantitative monitoring (i.e., PM10 and PM2.5) combined with qualitative analyses for VOCs.
Some people are sensitive to chemicals at lower levels. They can produce adverse effects like eye irritation, headaches, nausea, or odors, even at levels below the regulatory limits. If you smell it, it smells bad, or you’re experiencing headaches, nausea, etc., these are all signs of negative effects. It’s a struggle to reconcile experiencing these effects with being told that results are below levels of concern set by the government.
Over time, a plume may move within an aquifer. Vapors can migrate through soil into homes and elsewhere. This subsequent contamination, even years later, can cause significant problems for people in affected homes or buildings.
What happens next?
Spill response, clean up, and monitoring will continue until the EPA is satisfied. This will likely happen when results are at least under levels of concern (if not limits of detection) plus a lessening or lack of pressure by officials, locals, and others. Not all residents and members of the public will be satisfied with the response, especially those whose trust was lost. There will likely be ongoing research studies of longer-term effects on people, animals, vegetation, and levels in air, water, and soil. People will be concerned by any illnesses or deaths that appear out of the ordinary, or if a few are similar. Despite the aftermath and contamination of this train derailment, hazardous chemicals will continue to be moved by rail through cities and towns across the country.