Toxic Tuesdays

CHEJ highlights several toxic chemicals and the communities fighting to keep their citizens safe from harm.

What Scientists Know and Don’t Know About Exposures to Low Level Mixtures of Toxic Chemicals

Not long ago, the Huffington Post ran a story called: A Roll of the Dice: The Unknown Threat of Exposures to Chemical Mixtures, by Chris D’Angelo that talked about the difficulties scientists are having in answering the questions about adverse health effects following the horrific train derailment in East Palestine, OH more than a year ago. It’s an important article for anyone dealing with a toxic chemical exposure issue, especially in a community setting. 

It’s important because it gets to the heart of the science – what scientists know and don’t know about low level multiple chemical exposures to toxic chemicals such as occurred in East Palestine and many other contaminated sites around the country. In most cases, people are exposed to multiple chemicals simultaneously at low concentrations over various periods of time. Rarely are people exposed to just one chemical.

Yet when the government steps in to assess the health risks at these sites, they use the best tool available to them – risk assessments based on peer reviewed published data. The article discusses why this approach is very limited in what it can tell about the risks people face from exposure to multiple chemicals at low concentrations. Risk assessment is limited because virtually all of the published peer reviewed data addresses exposure to only a single chemical at a time and that very little data exists to inform what happens when people are exposed to multiple chemicals at low concentrations. Linda Birnbaum, former director of the National Institute of Environmental Health Sciences, told D’Angelo that mixtures are a complex problem that has long frustrated the field of toxicology.

The risk assessment process relies on this limited scientific data because it’s all we have to assess health risks. D’Angelo points this out arguing that data derived from exposure to one chemical at a time bears no relationship to the actual risks people face in the real world such as in East Palestine. He describes it this way: “In communities like East Palestine, Ohio, where residents were exposed to potentially dozens of different chemicals following the fiery derailment of a Norfolk Southern train in February, environmental agencies are often quick to declare the air, water, and soil safe, despite having little grasp of how substances could be interacting to harm human health.”

D’Angelo points out that the “…dangers in East Palestine may not be any one chemical but several working in tandem. And the fields of toxicology and epidemiology remain largely incapable of investigating and understanding that threat.”

But instead of acknowledging what the science actually tells us about exposures to low level mixtures of toxic chemicals, government, in the case of East Palestine, has released disingenuous and misleading statements meant to reassure the public that everything is alright and taking no action to address the adverse health symptoms that the people in East Palestine are continuing to experience including nose bleeds, headaches, skin rashes and breathing difficulties.

If the EPA and other health agencies were honest and truthful with the public, they would tell the people of East Palestine that they really don’t know the true exposure risks, that scientists don’t know very much about what happens to people exposed to low level mixtures of toxic chemicals. While perhaps not reassuring, the truth allows everyone to better understand what’ they are facing.  

The article concludes with a way forward by suggesting that EPA should follow the lead of what the government did to take care of Vietnam Veterans who were exposed to Agent Orange and the soldiers exposed to emissions from the burn pits in Iraq and Afghanistan, among others. In these cases, soldiers do not have to prove that their illnesses were caused by their exposure to toxic chemicals. If they can show that they were exposed, that’s sufficient for them to get health care and other compensation.

Communities like East Palestine shouldn’t be held to a different standard, especially given the many unknowns about the toxic exposures caused by the train derailment. In the absence of a basic understanding of what adverse health effects might result from exposures to the mixtures of toxic chemicals released into the community by the train derailment, the government should take steps to move the people of East Palestine who want to move, provide health care for those who were exposed and establish a medical monitoring program to follow these people.

These steps will begin the long and difficult process of acknowledging what we know and don’t know about exposes to low level mixtures of toxic chemicals and begin to learn what happens to the people exposed in these situations. Read the full article here.

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