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How AI Can Help Strengthen Grassroots Organizing

Image Credit: Tensorspark

By Gregory Kolen II.

Environmental justice is an issue that affects everyone, but those who bear the brunt of it are often the most vulnerable members of society. Disadvantaged communities, specifically, are often the ones living in areas with poor air quality, contaminated water sources, and unregulated disposal of waste. These challenges have been longstanding and difficult to overcome, as they require significant resources and political will. Yet, in recent years, emerging technologies such as Artificial Intelligence (AI) have emerged to support community leaders and organizations working towards environmental justice.

Boosting activism through data: AI can assess and analyze vast amounts of data to help grassroots organizers tailor their messaging based on the demographics, behavior, and attitudes of their target audience. By better understanding the needs of the communities they serve, organizers can create more effective and convincing campaigns that are more likely to drive action.

Streamlining operations: Organizers can improve the efficiency of their operations and decision-making processes, allowing them to work more effectively and achieve their goals more quickly. AI can help organizers automate routine tasks, which saves time and energy, allowing them to focus on more complicated tasks that require human expertise.

Amplifying voices: Magnify the voices of marginalized communities with AI-powered chatbots. Amplify the stories and experiences of those most affected by environmental injustices. This can help grassroots organizers build empathy and support for their causes among those in power, as well as among the broader public.

Improving outreach: Organizers can reach out to a more extensive and precisley targeted diverse audience. AI-powered tools can help create more targeted promotional materials and reach out to individuals who might not have been reached through traditional methods. This can help organizers increase the reach of their initiatives and attract more support.

Identifying environmental issues in communities: AI tools can help communities identify and monitor environmental hazards in their surroundings. For instance, using machine learning and remote sensing technologies, it is possible to map and classify toxic hotspots or areas with high pollution levels. Real-time air and water quality monitoring sensors can also provide early warning systems that allow communities to take the necessary precautions.

Empower communities through data and citizen science: Citizen science is an approach that empowers communities to gather data, conduct research, and create solutions. AI tools can help democratize scientific research by enabling communities to communicate their findings and analyses. Collectively, high-quality data can be used to ascertain environmental health disparities. For instance, EarthAI, a nonprofit organization, aims to provide equal access to AI-assisted satellite imagery, which can be used to map and track environmental health indicators.

Influencing Policies: AI tools can be used to predict the impact of policies on marginalized communities. For instance, researchers can use machine learning models to identify areas where environmental policy interventions are most needed, based on critical community characteristics and environmental hazards. Such data and insights can be shared with policymakers to develop effective policies that prioritize environmental justice.

There are numerous ways that emerging AI technology can be used to help strengthen grassroots organizing efforts for environmental justice. From boosting activism through data analysis to amplifying voices and improving outreach, AI has the potential to help empower grassroots organizers and create more profound change by identifying environmental hazards, empowering communities through data and citizen science, influencing policies, raising advocacy and awareness, and reducing disparities. While AI is not a magic solution, it has the potential to create a pathway towards a more just future and better outcomes for all communities.

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Health Effects of PFAS in Drinking Water

The glass is always... we're screwed comic.
Image credit: Jim Morissey

By Leila Waid.

As a research project for a university course, I conducted a literature review and systematic analysis of the health effects of PFAS in drinking water. This blog post contains a highlight and broad overview of the health effects discovered.

The systematic analysis included 44 observational epidemiological studies focused on PFAS-contaminated water as the exposure and adverse health effects as the outcome of interest. (For inquiries, references to individual studies, or any other information about the information about the systematic review study, email info@chej.org).

The results:

PFAS in drinking water is associated with a variety of different health effects. However, it is important to note that the results included here do not prove causation. In other words, the studies cannot prove that PFAS caused these health issues, only that an increase in PFAS exposure is associated with these health effects.

  • Cardiovascular health: increase in “bad” cholesterol, triglyceride lipids, blood pressure, hypertensive pregnancy disorder.
  • Hormonal health (endocrine system): impaired thyroid function, disruption in the growth hormone IGF-1 in children, lower levels of estradiol and testosterone, increase in Poly-Cystic Ovary Syndrome, fibroids, and testicular cancer.
  • Immune health: increase in adverse health effects from COVID-19, disruption in inflammation production, lower immune cell count and production, increase in ulcerative colitis (stomach ulcers).
  • Urinary system health: kidney function impairment, kidney cancer, bladder cancer
  • Digestive system: esophageal cancer.
  • Neonatal (infant) health: lower birthweight and small for gestational age.
  • PFAS has also been found to cause epigenetic changes, which is a process through which our environment impacts how our genes are expressed. In other words, it does not change the actual DNA structure, but how the body reads the DNA sequence. Specifically, PFAS is associated with DNA methylation (a process through which chemicals attach to a DNA chain and turn a specific gene on or off. This process affects how the gene is read).
  • Mortality: exposure to PFAS associated with all-cause mortality, as well as mortalities from liver cancer, cerebrovascular disease, diabetes, myocardial infarction, kidney cancer, breast cancer, and Alzheimer’s disease.
  • Neurological system: developmental language disorder.
  • Skeletal system: increase in bone fractures (hip, proximal humeral, and distal forearm fractures).
  • Non-regional specific: mesothelioma cancer (affects tissues around organs), increase in multi-morbidity (multiple chronic morbidities occurring at the same time).
  • Mental health: increased anxiety, financial stress around health issues, emotional distress due to worrying about living in PFAS-contaminated region. Also, PFAS was associated with an increase in behavioral problems among children. 

It is important to note that all the adverse health effects discussed above were found from observational studies on human health, not animal or in vitro (cell) studies. Although the findings cannot prove causation, they still paint an alarming picture for human health. The results showcase that urgent and robust policy action is needed at the federal and state levels to protect our waterways from PFAS contamination. This situation is critical because almost half (45%) of all tap water systems in the U.S. have PFAS contamination. And one study found that an estimated 97% of all Americans have PFAS in their blood streams.

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Toxic Tuesdays

Metals & Preterm Births

Toxic Tuesdays

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

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Metals & Preterm Births

Over 10% of births worldwide are preterm, meaning delivery occurs earlier than 37 weeks of pregnancy. It is a leading cause of neonatal mortality, and evidence suggests that exposure to heavy metals from the environment could be a risk factor. In the US, a major source of exposure to metals is private well water. The Environmental Protection Agency (EPA) sets standards and regulates levels of contaminants in public drinking water, but private well water isn’t regulated. This means private well water – which 13% of the US population receives drinking water from – is vulnerable to contamination. Indeed, studies have found metal contamination in private wells and that people who receive drinking water from private wells have more of these metals in their systems.

A recently published study set out to evaluate if exposure to toxic metals from private well water increased the risk of preterm birth. Because North Carolina (NC) has the largest state population using private well water, the researchers studied live births in NC that occurred from 2003-2015. From birth certificates, they could collect each pregnant person’s address at the time they delivered their babies. The researchers also used the NC-WELL database, which is a database of over 100,000 geocoded well water tests conducted from 1998-2019 from almost all census tracts in North Carolina. These tests include measurements of the concentrations of metals. The NC-WELL database allowed the researchers to assign each pregnant person’s address an estimate of their exposure to private well water and the concentrations of metals measured in that well water. Ultimately, the study included over 1.3 million births. This large sample size allowed the researchers to determine if increased metals in well water was associated with preterm birth.

The study found that people living in census tracts where over 25% of NC-WELL water tests exceeded EPA’s safe standard for cadmium had 11% higher odds of preterm birth than people who did not. People living in census tracts where over 25% of NC-WELL water tests exceeded EPA’s safe standard for lead had 10% higher odds of preterm birth than people who did not. These results indicate that cadmium and lead in private well water were each associated with preterm birth.

The study then modeled how the exposure to mixtures of metals was associated with preterm birth. This is particularly important because few studies assess the risks of multiple chemical exposures, even though it is highly likely people are exposed to more than one chemical at a time. When considering exposure to a mixture of seven metals present in private well water, the researchers found that exposure to the combination of cadmium and lead was associated with preterm birth.

In the US and NC, Black and Native American people have much higher rates of preterm birth than white people. Racial disparities in exposure to toxic chemicals could influence racial disparities in birth outcomes. As the study states plainly, “This is especially pertinent to consider when evaluating private well water-based exposure in NC, as structural environmental racism has led to poor and minority communities being more likely to rely on private well water.” This study found that when considering exposure to a mixture of seven metals present in private well water, the effect on preterm birth was most extreme for Native American people. It was associated with 20% higher odds of preterm birth for Native American people. The researchers say this disproportionate effect of metal exposure on preterm birth reflects the multiple environmental hazards and contaminants disproportionately forced on Native American people over several centuries. They also note that other studies have found that Native American pregnant people have higher levels of toxic metals in their systems than the national average.

This study used publicly available birth information and private well water testing to create a large cohort to study the effects of metals in private well water on preterm birth. The results make clear that private well water needs more regulation in order to ensure the levels of dangerous metals like cadmium and lead do not put people at risk. The results also make clear that not all people bear the same risks of exposure or health effects of exposure. People of color bear a disproportionate burden because they are more likely to receive private well water, which may contribute to disproportionate rates of preterm births.

For more information, CHEJ has previously written about the health effects of lead, cadmium, and the importance of considering the health effects of exposure to mixtures of chemicals.

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Using Scientific & Technical Information to Win

Photo credit: Milwaukee Area Technical College

By Stephen Lester.

I’m often asked what it is that I do at CHEJ. As a trained scientist, I provide technical assistance to grassroots community groups. People send me their environmental testing data to review. This data spans chemicals found in their drinking water, the air behind their child’s school or spouse’s factory, or the soil in the park where their children play. They ask me to do this primarily because they want to know what the results mean. But they also believe that if they gather enough information – the “right” information – and put it into the hands of the right decision-makers, they will do the right thing.  

So what do you think? True or false? Is information power? Can you solve your environmental problem(s) this way? No, you cannot. By itself, information is not power. It’s not the information but rather what you do with it that makes all the difference in the world. Just gathering data and sharing it no matter how important or impactful will likely not change a bureaucrat’s or a politician’s mind. But if you use the information in a thoughtful and strategic way, whether it’s to educate your community or others, and then to target the bureaucrats and politicians with a set of specific demands, you have a much greater chance to succeed. 

At CHEJ, we work directly with community leaders to help them become knowledgeable and proficient in understanding the technical, health, statistical and scientific aspects of chemical exposures. We also work with community leaders to help them understand how to use technical information to achieve their goals and win what their community needs to resolve. What we do includes reviewing testing data; cleanup plans; technologies for treating/disposing of hazardous waste and household garbage; reviewing plans to build new facilities; defining a community-based testing plan that includes where to test, what to test (soil, air, water), what to look for; evaluating a health study completed by a government agency or other entity; and so much more. CHEJ also has more than 50 guidebooks and fact-packs on a wide range of topics that you can use to focus your group on what it needs to be successful.

So don’t get trapped into believing you can win by gathering information, or become frozen into inaction until you gather a bit more information. What really matters is what you do with the information you have and how it strategically fits into your organizing plan. 

To learn more about CHEJ’s technical assistance services, see our website at http://chej.org/assistance/technical-assistance/.

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Toxic Tuesdays

How Individual Variability Affects the Toxicity of Chemicals

Toxic Tuesdays

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

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How Individual Variability Affects the Toxicity of Chemicals

It’s clear that not everyone responds to the same chemical exposures in the same way. There are many examples of this. The most striking is the person who smoked cigarettes for 30 years and never had breathing problems or developed lung cancer.  A major factor in why this happens is “individual variability.”

People process chemicals differently depending on internal factors. There are two major sources of variability in people. The first is variability in the penetration of a chemical to the target organ, referred to as pharmacokinetics. The second factor is the response of the target organ and biological system itself, referred to as pharmacodynamics. Pharmacokinetics is relatively well understood compared to pharmacodynamics.

There are four sources of variability in people: uptake, distribution, metabolism and excretion. Uptake of chemicals through breathing, referred to as respiratory absorption, is mainly influenced by the solubility of the chemical in the blood and its interaction with the respiratory surfaces in the lungs. The solubility of a single chemical in the blood can differ significantly from one person to another. Solubility in the blood can even change in a single person depending on food intake and diet. How much uptake occurs alters the concentration of a chemical in the body which in turn alters its toxicity. Similarly, dermal absorption, or uptake through the skin, depends on the exposed site, the condition of the skin, and the humidity and temperature of the environment. Uptake through the stomach, referred to as gastrointestinal absorption, depends primarily on stomach content.

The distribution of chemicals in the body is also highly variable and depends primarily on body size and composition. Chemicals that are soluble in fat, for example, will be distributed differently in people with different amounts of fat. Distribution is also affected by the degree to which a chemical can bind to molecules, mostly proteins, in the body. The amount of a chemical bound to proteins in a target organ determines how much damage a chemical can cause. Chemicals that are not bound in the body are more easily removed. Chemical binding can be altered if there’s competition for binding sites due to the presence of other chemicals or drugs in the blood system.

Metabolism plays a central role in how the body responds to a chemical and is probably the most important source of pharmacokinetic variability in people. The body has different ways it can interact with or metabolize a chemical. This interaction helps determine the body’s response to chemicals. In some instances, a chemical can become more toxic and in other instances, it can become harmless. Metabolism mainly takes place in the liver but can also occur in the skin and lungs. Metabolism can be altered by several environmental factors. For example, the simultaneous absorption of chemicals in high doses can slow metabolism because of competition for the metabolizing enzyme in the body. Genetic factors also play an important role in metabolizing toxic chemicals. Individual variability in genes results from differences in the DNA sequence of genes (called polymorphisms). These individual differences play an important role in a person’s response to chemicals such as in the development of cancer. Metabolism can also be affected by age and sex, environment, chemical intake, physical activity, protein binding and lifestyle.

Once a chemical has been absorbed, distributed, and metabolized, it will be excreted from the body. The primary way that the body excretes toxic chemicals is through the kidneys. Some excretion may also occur through the lungs, GI track, skin and mammary glands in pregnant women. Renal excretion is influenced by factors such as kidney function, protein binding, urine pH and urine flow, which also varies in individuals. Volatile chemicals, chemicals with a tendency to evaporate, are generally excreted by the lungs. Pulmonary excretion is determined by the same factors that influence pulmonary absorption.

These many sources of variability mean that two people can be exposed to the same concentration of a chemical but absorb, distribute, metabolize and excrete it differently resulting in a different response. This is why scientists and government health officials struggle to explain what will happen to a group of people exposed to the same mixture of chemicals. A person’s response is highly complex and the scientific understanding of how different variables influence toxicity is not well developed. These gaps in our knowledge reflect the many uncertainties in how chemicals produce their toxic effects on the human body.  

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Exposures to Chemical Mixtures Matter​

Toxic Tuesdays

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

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Exposures to Chemical Mixtures Matter

Considering cumulative exposures to low levels mixtures of chemicals is an enormous challenge when evaluating the toxicity of chemicals. Neither the EPA nor ATSDR have guidance on how to evaluate exposure to multiple chemicals simultaneously, or cumulatively over time. The EPA does have its Risk-based Screening Levels (RSLs) that provide some guidance on risk estimates, but these values only consider chemicals in isolation, or when exposed to one chemical at a time. This limitation has begun to be recognized as a fundamental weakness in the way research is done on the toxicity of chemicals. Testing one chemical at a time is not sufficient nor appropriate for evaluating public health risks when people are exposed to multiple chemicals at the same time, or cumulatively over time.  

This limitation was highlighted when a group of 350 cancer research scientists came together in Halifax, Nova Scotia to address the question of continuous multiple chemical exposures and the risks these exposures pose. Referred to as the Halifax Project, this effort merged two very distinct fields – environmental toxicology and the biological mechanisms of cancer – and provided the opportunity for researchers to look at the diversity of environmental factors that contribute to cancer by examining the impact that exposure to very small amounts of chemicals can have on various systems of the body.

These scientists looked at whether everyday exposures to mixtures of commonly encountered chemicals have a role to play in cancer causation. The researchers began by identifying a number of specific key pathways and mechanisms that are important in the formation of cancer. Then they identified individual (non-carcinogenic) chemicals that are commonly found in the environment that had some potential to disrupt these systems. A total of 85 environmental chemicals were identified.

The authors found that 59% of these chemicals (50/85) had low dose effects “at levels that are deemed relevant given the background levels of exposure that exist in the environment.” They found that only 15% of the chemicals reviewed (13/85) had a dose-response threshold and that the remaining 26% (22/85) could not be categorized due to a lack of dose-response information. The authors concluded that these results help “to validate the idea that chemicals can act disruptively on key cancer-related mechanisms at environmentally relevant levels of exposure.”

This is an important observation because it challenges the traditional thinking about how cancer forms in the body. It challenges the notion that all cancers share common traits (considered the “hallmarks of cancer”) that govern the transformation of normal cells to cancer cells. The authors also discuss how the results in this paper impact the process of risk assessment as even its most sophisticated model fails to address continuous exposures to mixtures of common chemicals. 

The authors concluded that “the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies.” In other words, exposure to multiple chemicals at low doses, considered individually to be “safe,” could result in various low dose effects that lead to the formation of cancer. This is a remarkable observation and conclusion. It is also an important advance in the understanding of the risks chemicals pose to society. It also highlights how surprisingly little is actually known about the combined effects of chemical mixtures whether on cancer related mechanisms and processes or on adverse effects in general.  

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Transgenerational Toxicity

Toxic Tuesdays

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

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Transgenerational Toxicity

While getting cancer, liver disease or central nervous system damage is often associated with exposure to toxic chemicals, one of the most sensitive targets of toxic chemicals is the reproductive system. This has long been recognized for over 50 years (1, 2, 3). In recent years however, research has shown that toxic chemicals can not only directly affect the reproductive system of both women and men, but that these effects can be passed on to the next generation and can even skip a generation. The impact of toxic chemicals on children with no direct exposure to these chemicals is known as a transgenerational effect.

A recent review paper reported that research on chemical toxicity, early life nutrition, smoking and radiation found evidence of harm even in offspring with no direct exposure to specific contaminants. This paper pointed to groundbreaking research at Washington State University that helped establish the principle of transgenerational toxicity by showing that the effects of toxic chemicals can extend even to the third generation of offspring. Other review papers have found a growing body of evidence from epidemiological studies that suggests that environmental exposures early in development have a role in susceptibility to disease in later life and that some of these effects seem to be passed on through subsequent generations (6, 7).

One important study that made this clear was a follow-up study on the residents of Love Canal in Niagara Falls, NY. This study, conducted by the New York State Department of Health (DOH), found that maternal exposure to chemicals from the Love Canal landfill was associated with an elevated risk of bearing a child with an adverse reproductive outcome. The researchers found that women who lived in the designated emergency zone while pregnant prior to the time of evacuation had a higher risk of having a preterm birth compared to women from other regions of the state. This effect was statistically significant.

There was also a greater than expected frequency of congenital malformations among Love Canal boys born from 1983 to 1996. These birth defects occurred in infants born to mothers who previously lived at Love Canal. The rate of these birth defects was about 50% higher than in boys born to mothers who lived in upstate NY. In addition, the ratio of male to female births was lower for children conceived at Love Canal. Lastly, women exposed as children had an increased risk of giving birth to a low weight baby.

These findings are consistent with the initial findings at Love Canal that led to the evacuation of the community in 1978 and 1980. The initial findings identified lower birth weight and increased congenital birth defects in infants, but were limited in defining the risk of adverse pregnancy outcomes because of small sample sizes.

This study is extraordinary because it looked at the reproductive outcomes of women after their exposure had stopped compared to other studies which typically evaluate health effects at the time when exposures were ongoing. In some cases, exposures to Love Canal chemicals occurred only when the women were children! These remarkable findings point out the subtle impact of exposure to toxic chemicals. They are a red flag for health concerns – especially for women of child bearing age – at other contaminated sites across the country. This study also highlights how little we really know about low level exposures to toxic chemicals.

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East Palestine, OH – Repeating the Mistakes of Love Canal

Photo credit: Pittsburgh Post-Gazette / Getty Images

By Stephen Lester.

Shortly after the horrific Norfolk Southern train derailment occurred in East Palestine, OH, I was invited to attend a town hall meeting organized by River Valley Organizing. The purpose of the meeting was to give people the opportunity to ask questions and hopefully, get some answers.

This was about 3 weeks after the rail company made the decision to spill the contents and then burn 5 tanker cars holding vinyl chloride and other toxic chemicals into a ditch alongside the railroad tracks at the site of the 38-car derailment. This intentional burn unleashed a gigantic black cloud full of particulates that enveloped the surrounding neighborhoods and farms in both Ohio and Pennsylvania (the accident was just a few miles from the state border).

It is well documented that burning chlorinated chemicals like vinyl chloride will generate dioxins. Dioxin is the name given to a group of persistent, very toxic chemicals that share similar chemical structures. The most toxic form of dioxin is 2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD. TCDD is more commonly recognized as the toxic contaminant found in “Agent Orange”  and at Love Canal, New York and Times Beach, Missouri. Dioxin is not deliberately manufactured. Rather, it is the unintended by-product of industrial processes that use or burn chlorine. It is also produced when chemicals like vinyl chloride are burned, such as what occurred in East Palestine.

At the town hall meeting, people talked about what it was like when the black cloud reached their property. One person who lived 15 miles away described burned ash material from the fire that settled on her property. Another who lived 3 miles away described how the black cloud completely smothered his property. People repeatedly asked: Was it safe for my kids to play in the yard? Is it safe to grow a garden? What is going to happen to my farm animals?

As I sat there listening, I was struck by how similar the questions were to what I had encountered when working at the Love Canal landfill in Niagara Falls, NY more than 40 years ago. People were raising important questions that deserve to be answered. But there were no clear answers. Just as it was at Love Canal.

It was also eerie how similar the response by the government authorities has been. Just like at Love Canal, the people of East Palestine are being told there’s no cause for alarm, that all the testing shows that no chemicals have been found at levels of “concern.” And just like Love Canal, the people in East Palestine are not buying it because they know things are not right. They are suffering from a range of respiratory and central nervous system symptoms including headaches, nose bleeds, runny noses, tearing eyes, and more.

As occurred at Love Canal, government scientists are not being honest with the people at East Palestine. If they did that, they would tell them what they know and what they don’t know. That would be helpful. But government won’t do that, because if they do, if they acknowledge how little is known about the link between adverse health effects and exposures to mixtures of chemicals, the people of East Palestine would demand action in the face of the huge uncertainties. Actions like paying for people to relocate from the area so that they can stop being exposed to the toxic chemicals – which are still in the air – or getting the health care they need and moving on with their lives.

It’s also unfortunate that so little had changed in the science of what we know about what happens to people who have been exposed to mixtures of chemicals like what occurred in East Palestine. This might have been understandable 40 or so years ago, but not today. It’s inexcusable that we didn’t learn from Love Canal and are repeating the same mistakes because we still know very little about widespread exposures to chemical mixtures.

The people in East Palestine deserve to be treated with respect and dignity and that includes expecting their government to act to protect their health in the face of the many uncertainties that exist in understanding the adverse health effects that result from these exposures. It’s time to do right by the people of East Palestine.    

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Toxic Tuesdays

Epigenetic Toxicity

Toxic Tuesdays

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

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Epigenetic Toxicity

The way scientists think about how chemicals cause their toxic effects is changing. Recent scientific research tells us that the traditional notion of how chemicals act is being replaced by a better understanding of the actual features of exposures that influence how chemicals express their adverse effects in people. These features include the timing and vulnerability of exposures, exposures to mixtures, effects at low doses and genetic alterations called epigenetics.

It wasn’t too long ago that scientists believed that the DNA in our cells was set for life, that our genes would be passed on from one generation to the next, and that it would take generations to change our genetic makeup. This is no longer the case.

A new research area, called epigenetics, is perhaps the fastest growing field in toxicology and it is changing the way we think about chemical exposures and the risks they pose. Epigenetics is the study of changes in DNA expression (the process of converting the instructions in DNA into a final product, such as blue eyes or brown hair) that are independent of the DNA sequence itself.

Researchers are learning is that the “packaging” of the DNA is just as important as a person’s genetic make-up in determining a person’s observable traits, such as eye color, or their susceptibility to diseases such as adult on-set diabetes or lupus.

We are learning that the environment is a critical factor in the control of these packaging processes. We may be born with our genes, but epigenetic changes can occur because of environmental influences and exposures during development and throughout life. These influences include reactions to the chemicals in the food we eat, the air we breathe, the water we drink, and they appear to contribute to the development of cancer and other diseases.

Researchers have found that the genome, which is a person’s complete set of DNA, responds to toxic chemicals in the environment that a person is exposed to. It can lead to changes in gene expression, not by mutating the genes, but by sending subtle signals that stops gene activity or turns them on at the wrong times. Researchers believe that the genome has evolved from adapting to stressful survival situations to becoming more vulnerable to adverse environmental exposures, which leads to direct changes in people’s health based on how they respond to toxic chemicals in their environment. Linda Birnbaum, the former director of the National Institute of Environmental Health Sciences and the National Toxicology Program, put it this way: exposure to gene-altering substances, particularly in the womb and shortly after birth, “can lead to increased susceptibility to disease. The susceptibility persists long after the exposure is gone, even decades later. Glands, organs, systems can be permanently altered.”

This growing field of epigenetic toxicity may explain the long-term effects of chemical substances and the predisposition to disease that some people have due to environmental factors including exposure to chemicals. Epigenetics may also help to explain why certain people develop diseases and others do not, or why the person who smoked for 30 years never developed lung cancer.

There is still much to learn, but an early lesson to take away from this emerging science is that we need to rethink our traditional ideas of how chemicals affect our health. This is especially true since regulators and public health scientists who make decisions about safe levels of exposure to toxic chemicals are not considering epigenetic toxicity in their evaluations and are missing a critically important piece of the toxic chemical exposure puzzle. This may help explain why government is constantly telling people that the testing that has been done shows no cause for concern, while the people who have been exposed have symptoms and illnesses with no explanation for why they are sick.  

For more information on epigenetic toxicity, see these resources:

1. https://www.healthandenvironment.org/environmental-health/social-context/gene-environment-interactions

2. https://www.sciencedirect.com/science/article/pii/S0278691517305240

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CTEH: The Fox in the Chicken Coop

Photo credit: Rebecca Kiger, The Washington Post/Getty Images

By Hunter Marion.

On March 12, 2023, ProPublica published an article in which CHEJ’s Science Director, toxicologist Stephen Lester, was commented as saying that “[Norfolk Southern] is responsible for the costs of cleaning up this accident.” The article went on to inform how the company was going about backing the bill for this cleanup.

Norfolk Southern has recruited the private environmental firm, Center for Toxicological and Environmental Health (CTEH), for the monitoring and removal of residual vinyl chloride and other chemicals. The problem with this choice is that CTEH has been the go-to company for alleged big polluters to utilize and sign-off on their controversial cleanups.

So, what is CTEH? It is an Arkansas-based company that, according to its website, is “committed to safeguarding your workers, your community, and the environment.” However, their record shows that this messaging is directed more towards compromised companies rather than harmed citizens. Starting in 1996, CTEH gradually gained prominence amongst alleged big polluters for performing toxicological evaluations and risk assessments that environmentalists would argue as being pro-industry.

  • In 2006, CTEH seemingly downplayed the health impacts of hydrogen sulfide in a report they wrote for the Chinese construction company, Knauf Plasterboard Tianjin, about their drywall. This drywall was later discovered to be highly toxic in 2009 and led to two giant class-action lawsuits in the U.S.
  • In 2008, 5.4 million cubic yards of coal ash broke through a 57-foot dike maintained by the Tennessee Valley Authority and flooded the town of Kingston, TN. While assessing the largest industrial spill in U.S. history, CTEH allegedly failed to meet quality assurance standards and used inaccurate air monitoring procedures during an audit. Arguably, the results of these actions disguised the true extent of the airborne coal ash that was present.
  • In 2010, CTEH purportedly underwent covert operations to release Corexit (a highly toxic dispersant) upon millions of gallons of crude oil during the Deepwater Horizon ocean spill. This resulted in the appearance of oil removal, until the following winter when it was shown that the oil was pushed further underwater and diverted to nearby watersheds and protected wetlands.
  • In 2016, a Husky Energy pipeline burst and poisoned a river with roughly 250,000 liters of crude oil within the James Smith Cree Nation in Saskatchewan, Canada. CTEH supposedly created a testing zone excluding the waterways most affecting the First Nations community. The results came back inconclusive, which likely justified Husky Energy to continue ignoring the community’s cries of concern.
  • In 2019, the International Terminals Company’s chemical storage facility in Houston, TX caught on fire. The resulting smoke cloud that covered most of the city released 9 million pounds of pollutants in one day, shutdown many municipal school districts with shelter-at-place advisories, and exposed the nearby city of Deer Park to extreme amounts of benzene (citizens later suffered severe symptoms). Afterwards, CTEH apparently performed insufficient air quality tests. Their dubious results were readily approved by the Texas Commission on Environmental Quality (TCEQ) and EPA.

Numerous toxicologists and environmental experts have decried CTEH’s methods as being suspicious to sinister. Activists and even politicians have warned against using their services (most notably during the Deepwater Horizon fiasco). Now, CTEH has been given the authority to control the narrative about how many toxic chemicals are truly present in East Palestine. As observed by former Exxon chemical engineer, Nicholas Cheremisinoff, CTEH is “essentially the fox guarding the chicken coop.”