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Toxic Tuesdays

N-nitrosodimethylamine (NDMA)

Toxic Tuesdays

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

N-nitrosodimethylamine (NDMA)

N-nitrosodimethylamine (NDMA) is a chemical in a class of chemicals called nitrosamines. NMDA is a yellow liquid but readily evaporates at room temperature.

Until the 1970s it was used to make rocket fuel, but was then discontinued because of the resulting environmental contamination. In the United States today, NDMA is only made for scientific research purposes. However, NDMA can be formed as a byproduct when its commonly found precursors come into contact with each other.

These scenarios where NDMA forms as a byproduct occur in industrial settings like water treatment plants, pesticide manufacturing facilities, and pharmaceutical manufacturing facilities. This can result in NDMA entering soil, drinking water, and air.

NDMA can also be formed from precursors found in common consumer products like lotion, cosmetics, beer, cured meat, and smoked meat. When we use these products, we can be exposed to the NDMA in them. Furthermore, foods like cured meat, smoked meat, fish, cheese, and beer are high in compounds called nitrates, which our bodies can convert into NDMA once we eat them. These kinds of consumer products are how most of the population is exposed to NDMA.
 
Exposure to NDMA can cause liver damage in humans. Workers exposed to NDMA in industrial settings had higher risks of liver, blood, bladder, stomach, and prostate cancers. Increased NDMA exposure through food is associated with stomach and colorectal cancers. In studies of laboratory animals, NDMA exposure
caused liver injury and stillbirth as well as liver, lung, kidney, and testicular cancers. Based on all of this evidence, the US Environmental Protection Agency and the International Agency for Research on Cancer both classify NDMA as a probable cancer-causing chemical in humans.

Because NDMA can be found in industrial settings and a wide variety of consumer products, it can be hard to know our exposure risk. This makes it particularly important for the federal government to regulate NDMA precursor chemicals in manufacturing, personal care products, and food preservation in order to keep people safe from the adverse health effects of exposure.
 

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Racial Disparities in PFAS Exposure Through Drinking Water

Toxic Tuesdays

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

Racial Disparities in PFAS Exposure Through Drinking Water

Per- and polyfluoroalkyl substances (PFAS) are a class of chemicals used in many consumer products and industrial processes since the 1950s. Because there isn’t federal regulation of their use or disposal, PFAS are commonly released into the environment. When PFAS are released, people can be exposed to them through air, dust, food, and water, so PFAS exposure is common in the United States. Biomonitoring studies have found that certain species of PFAS are present in the blood of almost all US residents.

Many species of PFAS are known to have adverse health effects on humans including increased cholesterol levels, changes in liver enzymes, decreased vaccine response in children, increased risk of high blood pressure in pregnant women, and decreased birth weight. Epidemiologic studies also show a link between exposure to certain species of PFAS and increased rates of kidney, prostate, and testicular cancer.

While there many ways to be exposed to PFAS, one of the most common is through contaminated drinking water. It is estimated that 200 million people in the US receive PFAS-contaminated drinking water. In 2018 New Jersey became the first state to adopt enforceable standards for PFAS in drinking water. It established maximum contaminant levels (MCLs) – which are the highest amount of a contaminant allowed in drinking water – for three of the most common species of PFAS: perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA). In April 2024, the US Environmental Protection Agency (EPA) announced the first federal drinking water standards for six PFAS including PFOS, PFOA, and PFNA.

In establishing MCLs for PFAS, New Jersey mandated statewide testing of all Community Water Systems (CWSs, the government-regulated water utilities) in the state. These CWSs tested by New Jersey serve 77% of the statewide population. A recent study used 2019-2021 CWS testing data along with Census data to evaluate if there are demographic differences in PFAS contamination of New Jersey residents’ drinking water. The study calculated quarterly averages for 491 CWs over this time period. It found that PFAS were detected above New Jersey’s MCL in 14% of CWSs, which serve 23% of the population. 

The study also mapped demographic information from census block groups – which are portions of census tracts and generally contain 600-3,000 people – onto the boundaries of each CWS. This created a map where the demographic makeup and quarterly average PFAS concentrations for each CWS were known. 27% of the non-Hispanic white population were served by CWSs with PFAS above New Jersey’s MCL. In contrast, 52% of the Asian population, 38% of the Hispanic population, and 34% of the Black population were served by CWSs with PFAS above New Jersey’s MCL.

These results demonstrate that not only is PFAS contamination prevalent in drinking water in New Jersey, but that there are racial disparities in PFAS contamination by CWS service area. Compared to white populations, Hispanic, Asian, and Black populations are more likely to receive drinking water that has PFAS contamination above the state’s safe threshold. These racial disparities in drinking water quality mirror racial disparities in the US more generally. Historical and ongoing housing discrimination leads to communities of color being excluded from living in certain areas. Throughout the country, pollution-emitting facilities are disproportionately located in nonwhite neighborhoods, driving health and environmental problems that disproportionately affect people of color. Industrial and military facilities that use PFAS and are located in nonwhite neighborhoods may contaminate the water supplying nearby CWSs, which could explain the racial disparities in drinking water discovered in this study.

It is important to note that EPA’s new MCLs for PFAS species are below New Jersey’s MCLs. Complying with these federal standards could reduce racial disparities in PFAS water contamination in New Jersey, but only with robust federal enforcement. People in New Jersey and across the US – especially people of color who have been disproportionately harmed – need enforceable standards and effective enforcement of those standards in order to be safe from PFAS in their drinking water.

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The Government’s Approach to Evaluating Health Problems in Communities

Toxic Tuesdays

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

The Government’s Approach to Evaluating Health Problems in Communities

Communities exposed to toxic chemicals from industrial pollution struggle to get answers about whether the pollution has caused the health problems in their community. Groups organize to pressure the government to stop the pollution and to clean up the contamination. But these agencies have few answers and often little is done. Frequently states ask the Agency for Toxic Substances and Disease Registry (ATSDR) to investigate the health problems reported in a community. Initially, ATSDR is welcomed because people think that someone is finally going to provide some answers about the health problems in the community.

The Agency for Toxic Substances and Disease Registry (ATSDR) was created in 1980 to address health problems at Superfund sites. Their mission is to protect communities from harmful health effects related to exposure to both natural and man-made hazardous substances. ATSDR is the right agency to evaluate health complaints in a community and they have been doing so for more than 30 years. And for most of this time, the agency has repeatedly failed to answer the questions people raise about whether there’s a link between health problems and the pollution in the community. CHEJ has written much about ATSDR over the years1.

Last month an investigative report by the news service Reuters took an extensive look at ATSDR’s work. The report, “How a US health agency became a shield for polluters,” analyzed 428 reports issued by the agency from 2012 to 2023. Those reports contained 1,582 conclusions about potential harms at contaminated sites. Reuters found that in 68% of its findings, the ATSDR declared communities safe from hazards or did not make any determination at all. That record of finding little harm “strains credulity,” said one former EPA official quoted in the report.

Other key findings included:

  • The agency’s frequent declarations of no harm often are rooted in faulty research. At least 38% of the time, agency reports show, its researchers relied on old or flawed data.
  • At least 20 times from 1996 to 2017 the agency declared that a potential hazard posed no health risk – only to be refuted later by other government agencies or the ATSDR itself. The errors impact communities in AlabamaCaliforniaMissouriNew York and North Carolina.
  • Despite decades of criticism, the agency continues to publish research that relies upon practices its own review board called “virtually useless.”
  • The agency’s common practice of publishing inconclusive reports feeds a long-standing corporate strategy of using scientific uncertainty to deflect regulation and liability for polluted sites.

How is it possible that ATSDR has operated like this for so long? Some answers come from a symposium hosted by ATSDR in 2012 on the Future of Science at ATSDR2:

“In conducting its core work of assessing health risks at contaminated sites, ATSDR has faced a large workload with limited authority and resources to collect needed data. Moreover, concerned communities have voiced legitimate public health questions that ATSDR could not answer fully with existing scientific tools and knowledge.

This meeting documented many scientific limitations and challenges facing the agency. ATSDR’s Board of Scientific Counselors hired a consultant who reviewed the agency’s scientific work and came to these conclusions and observations:

  • An alarming gap persists between public expectations and the limited tools available to scientists to assess the public health effects of hazardous waste sites and uncontrolled releases. This gap is due, in part, to the inherently complex and uncertain relationship between diseases and chemicals emanating from hazardous waste sites and uncontrolled releases. Many substances commonly found at hazardous waste sites and in uncontrolled releases may also emanate from other sources and are routinely detected at low levels in air, water, food, consumer products, or other media. No field-based methods are readily available for measuring the portion of a particular ambient exposure or internal dose that is attributable to a specific hazardous waste site or uncontrolled release.
  • In the absence of scientific methods for assessing the unique contribution of releases from hazardous waste sites and uncontrolled exposures to disease, ATSDR scientists rely upon surrogate methods and designs (e.g., comparing exposures to disease rates in communities with a hazardous waste site with “background” levels). Such approaches, although squarely within the mainstream of environmental science, typically are not robust enough to detect adverse health effects caused by site-specific exposures to toxic chemicals.
  • EPA and ATSDR scientists calculate theoretical risk estimates based on a host of assumptions about contaminant concentrations, exposure duration, characteristics of the exposed population, acute and long-term health risks and other factors.
  • ATSDR relies predominately on environmental data collected by other agencies (primarily EPA and state agencies) for its health assessments. Such data often are not adequate or appropriate for addressing specific questions about current exposures and pathways.

Without good tools to evaluate the impact of chemical exposures on people, ATSDR, EPA and other government agencies will continue to struggle to address pollution and contamination in communities. It’s time to recognize and to acknowledge that scientists know very little about how exposures to toxic chemicals, especially to low level mixtures, lead to adverse health outcomes.

Instead of trying to link cause and effect (the agencies default approach), which is virtually impossible to achieve because of the inherently complex and uncertain relationship between disease and chemical exposure and the limited tools to evaluate health effects, isn’t it time to consider whether there’s enough information and evidence about exposure and adverse health problems in a community to take action to protect people exposed to toxic chemicals?

Until there is a change in how government approaches health problems in a community, you can expect ATSDR to continue to investigate health problems in communities using the same approach that’s reflected in the Reuters article.


(1)  – CHEJ, Assessing Health Problems in Communities, S, Lester, Updated Jan 2010; CHEJ,  ATSDR: Don’t Ask… Don’t tell… Don’t Pursue, S. Lester, 1994 (available from CHEJ).

(2) ATSDR: The Basics, The Future of Science at ATSDR: A Symposium, Atlanta, GA, April 11-12, 2012 (available from CHEJ).

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Acrylamide

Toxic Tuesdays

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

Acrylamide

Acrylamide is a clear, odorless chemical. It has many industrial uses, including treating waste water
discharge from water treatment plants. It is also used in the production of industrial products like dyes,
paper pulp, grout, plastics, and construction materials. Many consumer products are also produced
using acrylamide, such as contact lenses, cosmetics, fabrics, textiles, and sugar. When acrylamide enters
the environment, people are most likely to be exposed to it by drinking contaminated water. Acrylamide
can enter drinking water through the water treatment process or through improper disposal from
industrial facilities that use it to manufacture products.

Exposure to acrylamide can have serious effects on the brain, causing numbness in the hands and feet,
disorientation, loss of balance, and muscle weakness. Skin contact with acrylamide can cause irritation,
dermatitis, and nerve damage. Studies in laboratory animals have found that acrylamide exposure can
also cause defects in the male reproductive system, but it is unknown if it has the same effects in
humans. Based on studies in laboratory animals, the US Environmental Protection Agency classifies
acrylamide as probably causing cancer in humans. The International Agency for Research on Cancer
classifies it as likely causing cancer in humans.

In 2002, acrylamide was discovered to form when foods rich in starch are grilled, baked, or fried above
250°F. This includes foods like potato chips, French fries, and breakfast cereals. The resulting acrylamide
can be found in the dark brown or burnt areas of these foods. Since this discovery, many regulatory and
public health agencies across the world have called for more research into whether this dietary
exposure to acrylamide increases the risk for cancer. The American Cancer Society says that based on
existing studies in humans, dietary acrylamide exposure is unlikely to be linked to increased cancer risk.
However, the ACS says that more research on this topic is needed to fully know if dietary acrylamide
poses a cancer risk. This research will be crucial in understanding how widespread cancerous acrylamide
exposure may be.

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Styrene

Toxic Tuesdays

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

Styrene

Styrene is a chemical compound that can be linked together with itself or other compounds to create strong, flexible polymers that make up plastics, rubbers, and resins. Many products such as foodware containers, printer toner, shoes, plastic pipes, carpeting, fiberglass insulation, and automobile parts contain styrene.

Styrene can enter the air, water, and soil through manufacturing and disposal of styrene-containing products. Styrene is a colorless liquid but it readily evaporates, so a large portion of styrene that enters water or soil ends up in the air. While manufacturing and disposal can cause exposure, most people are exposed to styrene through their use of styrene-containing products.  For example, people inhale it indoors because styrene-containing building materials and printers release styrene vapors. In addition, the styrene in foodware containers can migrate into the food they hold, causing people to ingest styrene.

Once inhaled or ingested, styrene can have many adverse effects on the body. Many of these effects are in the brain, such as impaired vision, impaired hearing, loss of coordination, slowed reaction time, fatigue, and difficulty concentrating. Studies in laboratory animals have found that styrene exposure can also cause damage to the liver, though it is unknown if it has this effect in humans. The US Department of Health and Human Services classifies styrene as being reasonably anticipated to cause cancer. The International Agency for Research on Cancer classifies styrene as probably causing cancer. The pervasiveness of styrene-containing plastics in consumer and industrial products makes these adverse health effects particularly concerning. Decreasing the reliance on plastics – through government regulation, scientific innovation, and consumer education – would help protect people from styrene exposure and its associated health effects.

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Linking Exposure and Health Outcomes

Toxic Tuesdays

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

Linking Exposure and Health Outcomes

One of the hardest things for a public health scientist to do is to link a specific health problem that a person is suffering from to a specific exposure to a toxic chemical(s). People who have been exposed to toxic chemicals, whether they lived at Love Canal, NY, Flint, MI or East Palestine, OH, want to know if their cancer, diabetes or other illness was caused by exposure to toxic chemicals. This is a reasonable question for people to ask, and it is one we hear all the time from people in the communities we work with. Unfortunately, the answer is not so clear. 

The problem is that scientists know very little about how and why the body responds to toxic chemicals the way it does. While we know a great deal about the mechanism of action for some chemicals such as dioxin and lead, we do not know what is going to happen to an individual who is exposed to 5 parts per trillion (ppt) of dioxin in their food. Or to a child who eats lead paint chips for 3 months. In some cases, scientists can predict what symptoms to expect, but it is rare that they can confidently link specific health outcomes to specific exposures even in obvious situations like the drinking water disaster in Flint, MI.

In fact, there are only two chemicals – asbestos and vinyl chloride – out of the more than 80,000 chemicals in use today, that scientists have been able to clearly link between exposure and specific health problems. In the case of asbestos, if you were exposed to asbestos in the shipping industry and develop a rare cancer of the outer lining of the lungs called mesothelioma, scientists are 99% confident (as close to certain as one can get) that the asbestos caused your lung cancer. In the case of vinyl chloride, if you were exposed to vinyl chloride in a PVC manufacturing plant and develop a rare cancer of the liver called angiosarcoma, scientists are 99% confident that the vinyl chloride caused your liver cancer. In both cases, it was an observant clinician who noticed that the people with these rare cancers all worked at the same place and had similar exposures.   

There are several factors that determine what happens when a person is exposed to chemicals. These factors include an individual’s susceptibility (this varies greatly from person to person), how long exposures occur, how many chemicals a person is exposed to, the concentration of these chemicals, and the toxicity of the chemicals. Add in the reality that people are often exposed to more than one chemical at a time and often repeatedly over time, then the certainty over what is known becomes significantly less. Even if you knew all these factors (which is rare), it is still almost impossible to predict what will happen when a person is exposed. We’ve touched on many of these factors in previous issues of Toxic Tuesday.

In addition, there is no way to fingerprint an exposure to tie it to a specific health outcome. And many symptoms or diseases are not specific to a particular chemical. In most instances, there can be many causes of the symptoms that people are having. And few physicians have experience with exposure to toxic chemicals. Meaning they cannot distinguish whether the headache you are suffering from resulted from the chemicals you were exposed to or whether you had a hard day at work. Often this inexperience leads to blaming the victim for their situation rather than looking at chemicals as a possible explanation. Another problem is determining what the “normal” rate of illness or disease is in a community. Scientists simply cannot decide what is normal. This is in large part because of the many uncertainties already discussed.

Despite the many scientific uncertainties, linking cause and effect has become the standard to achieve before government will take action to address a pollution problem or protect a  community. Over the years, this has meant endless studies and years of research gathering data that has resulted in little or no action on the part of government to protect people and communities exposed to toxic chemicals. This has been the government’s approach since before Love Canal more than 40 years ago. This is what is happening now in East Palestine, OH. This is no longer reasonable nor acceptable.

It is time to acknowledge that scientists do not know very much about how or why exposure to toxic chemicals, especially at low-level mixtures, leads to adverse health outcomes. Instead of trying to link cause and effect, which is virtually impossible to achieve because of the lack of information and understanding, it is time to consider whether there is enough information and evidence about exposure and adverse health problems in a community to take action to protect people exposed to toxic chemicals.

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

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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Carbon Monoxide

Toxic Tuesdays

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

Carbon Monoxide

Carbon monoxide is a toxic gas that is difficult to detect because it has no smell, taste, or color. It can be produced from both natural and human-made sources when carbon fuel – such as gasoline, wood, coal, charcoal, propane, natural gas, or trash – is incompletely burned. The most common source of carbon monoxide in outdoor air is exhaust from gas-powered vehicles. It can also be produced in indoor air through house fires or use of gas-powered appliances such as portable generators, furnaces, water heaters, stoves, and fireplaces. Carbon monoxide is also produced in industrial chemical manufacturing to create a group of plastics called polycarbonates.

When carbon monoxide enters the air it can remain there for several months. Inhaling air contaminated with carbon monoxide interferes with red blood cells’ ability to carry oxygen throughout the body. This can cause difficulty with breathing, headache, nausea, dizziness, vomiting, vision impairment, confusion, and chest pain. In high doses it can cause seizures, coma, and death. Exposure to high doses while pregnant can also cause miscarriage. People with heart or lung diseases are particularly vulnerable to the effects of carbon monoxide exposure. Even once exposure to carbon monoxide has ended, there can be long-term effects on heart and brain function.

Because of the extreme toxicity of carbon monoxide, the Environmental Protection Agency (EPA) sets standards for safe levels of carbon monoxide in the air. Despite these standards, studies estimate that 50,000 people in the United States need emergency medical treatment for carbon monoxide exposure each year, and that about 1,000 die from carbon monoxide exposure each year. Carbon monoxide has also been found in many Superfund sites identified by the EPA. These realities indicate that more stringent standards, testing, and regulations may be necessary to keep people safe from carbon monoxide.

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Acrolein

Toxic Tuesdays

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

Acrolein

Acrolein is a toxic chemical that presents itself as a clear to yellowish liquid that evaporates quickly and is highly flammable. As it vaporizes, it has an unpleasant smell and tends to accumulate in low areas since it is heavier than air. Acrolein is used as a precursor ingredient in many different kinds of manufacturing industries including plastics, paint, leather finishings, and paper coatings. It is also used as a biocide to control plant and algae growth in water systems.

Acrolein exposure usually occurs in the form of inhalation. Acrolein is formed from the combustion of certain organic compounds. As such, it is commonly formed from the burning of fossil fuels, animal and vegetable fats, and tobacco. It is a common, albeit minimal, by-product of forest fires.

The health effects of short-term exposures to acrolein are fairly well understood. Acrolein is severely irritating to skin, eyes, and mucous membranes. If inhaled, it causes respiratory distress, an asthma-like reaction, and delayed pulmonary swelling. Contact with the skin or eyes produces irritation and lacrimation, and can result in chemical burns.

The long-term health effects of acrolein are much less studied. There are some indications that prolonged exposure can cause respiratory sensitization, a process through which exposure to a chemical leads to hypersensitivity of the airways when exposed again to the same or similar chemicals. Potential adverse reproductive effects or links to cancer have not been explored well enough to draw any conclusions.

It is perhaps this uncertainty over long-term health effects that most concerns residents of East Palestine, OH. After the train derailment dumped more than 1 million pounds of various industrial chemicals in the community, authorities responded by removing some of the contamination and performing controlled burns on the rest. These activities have released dangerous levels of acrolein into the air, as an analysis of EPA data by Texas A&M researchers revealed. Despite accurately assessing the immediate health impacts of acrolein on the community, it is a shame that the same researchers then downplayed the risks of prolonged exposure by saying that “it would take months, if not years, of exposure to the pollutants for serious health effects.” This is simply not true, as we have very little information about long-term exposure to even low levels of acrolein. The situation in East Palestine is extremely worrisome, and researchers downplaying the health risks the community is facing is very counterproductive to the situation.

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Glyphosate Risks

Toxic Tuesdays

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

Glyphosate Risks

Glyphosate is a chemical found in weed killer products like RoundUpTM used on farms and home lawns. Because of its effectiveness, glyphosate has become the most widely used herbicide in the world. People who work with these products and people who live near farms where they are used can get exposed to glyphosate through the air. The International Agency for Research on Cancer (IARC) has concluded that glyphosate exposure probably causes blood cancers. 81% of American adults and children have detectable concentrations of glyphosate in their urine. While much is still unknown about the potential health risks of glyphosate exposure, two recently published studies illuminate how big a concern it may be for both workers and the public.

One study aimed at assessing the potential cancer risk posed to farmers who work with glyphosate-containing herbicides. The study used data from the Agricultural Health Study (AHS), which collected biological samples from private and commercial pesticide applicators in Iowa and North Carolina from 1993-1997. The study analyzed AHS participants who were male, above the age of 50, had no blood disorders, and had not been diagnosed with cancer, which created a sample of 1,681 people. The researchers analyzed the DNA of these participants to look for the loss of large portions of DNA in the Y chromosome. Significant loss of DNA portions can have a massive effect on how the body’s cells function and have been linked to increased risk for cancer. Losses of large portions of DNA in the Y chromosome have been specifically linked to blood cancers like those that may be caused by glyphosate exposure.

In the study, 21% of participants had lost large portions of the DNA in their Y chromosome in some of their cells. Statistical analysis found that using glyphosate-containing pesticides for either a longer period or with more intensity were both associated with more DNA loss in the Y chromosome. While these findings do not prove that occupational exposure to glyphosate causes cancer, they provide important biological evidence that glyphosate exposure can cause the kinds of largescale changes in DNA that are associated with cancer. It is the first study of agricultural workers to show this association between glyphosate and DNA loss.

A second study sought the extent of glyphosate exposure among people who live near farms where glyphosate is used. Some studies have shown that glyphosate exposure during pregnancy is associated with reduced fetal growth and pre-term birth. Thus, this study focused on measuring glyphosate levels of pregnant people in Idaho who live near farms that use glyphosate. The study included 40 participants in Idaho who were in their first trimester of pregnancy in 2021. Researchers collected weekly urine samples from participants until delivery. Half of participants lived near farms (less than 0.5 kilometers from a farm) and half lived far from farms (more than 0.5 kilometers from a farm). About two-thirds of both groups had detectable concentrations of glyphosate in their urine.

For participants living near farms, the frequency and concentration of glyphosate detection in urine increased significantly during the pesticide spray season (from May to August) compared to the non-spray season. This change did not occur in participants living far from farms, indicating that increased exposure to glyphosate was likely a result of pesticide spraying. While these findings do not directly track the health effects on pregnant participants or their infants, it is important biological evidence that agricultural use of glyphosate exposes nearby residents. It is the first study to demonstrate that residential proximity to farms using glyphosate is associated with increased glyphosate in the body.

These two studies demonstrate that glyphosate may pose risks to both workers and the public. CHEJ has previously written about the uses and health risks of glyphosate here.

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