For what it’s worth, the questions being asked here sound familiar to those of us who witnessed the Love Canal event in real time…
The complete report is a the link below
- Ralph
https://cen.acs.org/safety/Ohio-train-derailment-raises-questions/101/web/2023/02
Ohio train derailment raises more questions
Scientists and residents ask about the testing behind official assurances
Environmental chemists, community advocates, and local residents say they are concerned about the thoroughness of tests performed by federal and state authorities to determine the safety of air and water in East Palestine, Ohio, where a freight train carrying vinyl chloride and several other chemicals derailed and burned earlier this month.
Related: Safety questions remain after Ohio train derailment
Many also express frustration in accessing the information underlying assurances from the US Environmental Protection Agency and the railroad, Norfolk Southern, that residents could return to their homes 6 days after the accident.
The EPA, meanwhile, has published a more comprehensive list of the chemicals the train was carrying than was available in the week after the Feb. 3 derailment. In addition to vinyl chloride, the focus of initial concern, ethylhexyl acrylate, ethylene glycol monobutyl ether, butyl acrylate, and isobutylene—all hazardous chemicals—were released and found in water samples taken from the Ohio River, a major source of drinking water.
Scientists and residents welcome the additional information but agree that it raises questions about whether initial air monitoring checked for chemicals of most concern.
Peter DeCarlo, an associate professor in the department of environmental health and engineering at the Johns Hopkins Whiting School of Engineering, says it is apparent from details released by the EPA that testing before the lifting of the evacuation order in East Palestine was done with handheld monitors that provide real-time measurements of volatile organic compounds as a class. Such monitors can provide false negative readings, says DeCarlo, who studies air pollution.
“Part of the problem is that the monitors are not sensitive enough to measure the low concentrations needed for understanding health impact,” he says. “And they are not measuring for specific chemicals. DeCarlo says aerial testing undertaken by the EPA on Feb. 7, the day after a controlled release and burn of vinyl chloride in five railcars, provided more useful information by mapping out downwind chemical plumes. But most of the air monitoring data he has seen is from tests performed on the ground in East Palestine, he says.
“As an atmospheric chemist and environmental engineer, I would want to sample upwind of the site, at the accident site, and downwind of the accident site,” DeCarlo says. “It is that kind of measurement setup that would provide key information for understanding emissions from the site.”
Air sampling, as opposed to monitoring, provides much more chemically specific data, DeCarlo says. In this approach, stainless steel containers are filled with air at a particular place and time and taken to a lab where advanced analytic technologies, generally gas chromatography-mass spectrometry, characterize the chemicals in the sample.
“I haven’t seen any samples taken at the site,” he says. “Most of the air sampling data I’ve seen has been from samples taken in East Palestine, which is understandable; it’s where people in town live. But this doesn’t tell us about the downwind impacts and it doesn’t tell us about any continuing emissions from the site.”DeCarlo adds that air impact tends to be highest immediately after an incident and in the days following.
“Water and soil can have a longer memory than that air,” he says.
Carsten Prasse, an assistant professor in the department of environmental health and engineering at Johns Hopkins Whiting who focuses on water contaminants, says water testing must be done on surface water—in this case the Ohio River and tributaries—as well as on ground water.
The impact of water pollution occurs over a long period, Prasse says. “A lot of chemicals have low solubility, but that doesn’t mean they aren’t soluble at all.” Chemicals that infiltrate the ground can slowly seep into ground water.
Testing at the accident site is important to determine the presence of ground water, its depth, the direction it is flowing, and its proximity to sources of drinking water, including private wells. Groundwater migrates slowly, Prasse adds. Long-term monitoring of test wells in the area would be one approach going forward.
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