A plan to test for toxic dioxins near the site of a February train wreck in East Palestine, Ohio, is flawed and unlikely to find the dangerous substances, independent chemical pollution researchers in the US who reviewed the testing protocol told the Guardian.
Initial soil testing already revealed dioxin levels hundreds of times above the threshold that Environmental Protection Agency scientists have found poses a cancer risk, but that sampling was limited in scope.
Regulators have said further testing being conducted by the Norfolk Southern-funded contractor Arcadis US will provide a broader picture than the initial samples. But, among other problems, the plan relies on what experts characterized as an “unconventional” process to check for dioxins, and the results are “unlikely to give a complete picture”, of contamination in East Palestine, said Stephen Lester, a toxicologist with the Center for Health, Environment and Justice.
“It is very limited and I don’t think it’s going to answer the questions people in East Palestine have about dioxin exposure and the risk they have from dioxin exposure,” Lester added.
Arcadis noted its plan was developed “in consultation with” the EPA, but, among other concerns, dioxin researchers who reviewed the plan noted:
Arcadis will largely rely on visual inspections of the ground to find evidence of dioxins, instead of systematically testing soil samples that may contain the compounds, which is standard protocol.
The plan does not say how low the levels of dioxin the company will check for will be.
Testing will only be conducted up to two miles from the accident site when ash has been found up to 20 miles away.
The testing is limited to soil and does not include food or water.
The EPA did not immediately respond to a request for comment. The agency’s response to the train crash has drawn intense criticism from the town’s residents and public health advocates who say it has failed to protect East Palestine from toxic chemicals spilled from the cars, as well as dioxins probably released from a controlled burn of vinyl chloride days after the wreck.
After resisting calls for weeks to test for dioxins, the EPA on 3 March announced it would order Norfolk Southern to do so. Dioxins are a class of chemicals that are a byproduct produced when chlorine is burned. Chlorine is a common industrial ingredient used to make products like PVC.
Dioxins are highly persistent and can accumulate and stay for years in the environment or human bodies. The compounds are linked to cancer, diabetes, heart disease, nervous system disorders and other serious health problems. Soil and food contamination are considered to be among the most common exposure routes.
Dioxin researchers who reviewed the plan were most “troubled” by how Aracadis plans to visually inspect the ground for evidence of ash. If ash is found, then soil in that area will be tested.
“Visual inspection results will guide sample collection, with samples collected from both visible ash material and shallow soil if ash material is present,” the testing plan states.
But the controlled burn occurred about six weeks ago, and experts say most of its ash will have been blown away or washed away by precipitation.
“They’re not likely to find very much, if anything, because that is a very unusual approach for testing an area that has been contaminated,” Lester said.
The testing plan should include “structured sampling” in which a grid is created around the site and soil samples are taken about every 10 meters, said Linda Birnbaum, a former head of the US National Toxicology Program and EPA scientist.
The plan also limits testing to two miles around the site, but ash has been reported as far as 20 miles away, and dioxins are known to move long distances through the atmosphere.
“Why would you limit sampling to where you see ash on the ground … and why are they limiting it to two miles at max? Air travels further,” Birnbaum said.
The plan also limits testing to soil, but food is the main dioxin exposure route, noted Mike Schade, a public health advocate with the Toxic Free Future non-profit. Dioxins in soil are taken up by crops and build up in the tissue of animals that eat the crops. Humans are exposed via contaminated meat, eggs, milk or farm products, and the chemicals can also accumulate in fish.
“They need to significantly expand the scope of testing to determine if other environmental media such as farms and bodies of water have dioxin,” Schade said.
Lester noted that the plan characterizes the visual inspections as the first phase of testing and seems to leave the door open for more sampling in media other than soil, if dioxin is found, but the test seems designed to find little dioxin, Lester said.
“I’m very leery about that because if the testing is done by a visual inspection then they probably will not find anything and will have no reason to do more testing,” he added.
In the previous round of testing, Indiana’s government checked several soil samples because it was storing contaminated soil from the Ohio derailment in its landfills.
Regulators establish the toxicity of dioxins in a soil sample by calculating the “toxicity equivalence” of all dioxins in the soil compared with the most toxic dioxin compound, called 2,3,7,8 TCDD. East Palestine soil showed levels of “2,3,7,8 TCDD toxicity equivalence” of 700 parts per trillion (ppt).
The contamination level at which the EPA will initiate cleanup action in residential areas is 1,000 ppt. But EPA scientists in 2010 put the cancer risk threshold for dioxins in residential soil at 3.7 ppt, and the agency recommended lowering the federal cleanup trigger to 72 ppt. The Obama administration killed the proposed new triggers.
Meanwhile, many states will act on a cleanup at much lower levels than the EPA, including at 90 ppt in Michigan, and 50 ppt in California. Federal cleanup standards of 1,000 ppt apply in Ohio.
Those who reviewed the dioxin testing plan said they could not speculate on why it was designed as is. But Schade noted Norfolk Southern “has a vested interest in not finding dioxin” and the company long ago lost the trust of East Palestine residents and public health advocates. He said East Palestinians need to be involved in the decision making process, and EPA needs to do its own testing, for the results to be viewed as legitimate.
“I’m not saying Norfolk Southern’s consultants are going to purposely do a poor job, but if this data is going to be trusted by the community, then the EPA needs to take over and do the work,” he said.