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Toxic Tuesdays

How Individual Sensitivity Affects Toxicity

Toxic Tuesdays

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

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How Individual Sensitivity Affects Toxicity

We previously addressed individual variability and how it affects a person’s response to toxic chemicals. Another important factor in toxicology is a person’s individual sensitivity to chemicals. How sensitive a person is to chemical exposure helps determine how susceptible or vulnerable they are to toxic chemicals. Several factors determine how sensitive a person is including age, sex, health, genetics, diet, lifestyle, preexisting conditions and previous environmental exposures. While some people are more sensitive to chemical exposures than others, there is no clear definition of what sensitivity is or what it means. This is partially since so little is understood about the human response to toxic chemicals, especially to low level mixtures of chemicals.

Because of this uncertainty, there is no generally accepted definition of sensitivity. Nicholas Ashford and Claudia Miller describe the various meanings of the term. In traditional toxicology, sensitivity has been defined as individuals who require relatively lower doses to induce a particular response. These individuals are considered more sensitive than people who require relatively higher doses to experience the same response. The distribution of this population is described by the classic bell curve where the sensitive and resilient populations are found in the tails of the curve. Most people fall into this response category. In traditional medicine, sensitivity has been defined as individuals who have a significant and rapid immune-mediated response to an allergen or agent. In this population, some individuals, described as chemically sensitive, have a striking immune response to an allergen or agent, while non-allergic individuals do not, even at high doses. Classic allergens include ragweed or bee venom, but also include chemicals such as nickel or toluene diisocyanate (TDI).

In recent years, a growing population of people have expressed an entirely different sensitivity response. These are people who have developed multiple chemical sensitivities. Ashford and Miller found that people who have developed multiple chemical sensitivities may exhibit a third and entirely different type of sensitivity. These authors stated this about people with multiple chemical sensitivities (MCS): “Their health problems often (but not always) appear to originate with some acute or traumatic exposure, after which the triggering of symptoms and observed sensitivities occur at very low levels of chemical exposure. The inducing chemical or substances may or may not be the same as the substances that thereafter provoke or ‘trigger’ responses.” Unlike classical toxicological or immune mediated responses, people with MCS sensitivity respond in a two-step process of an initial exposure event followed by a second triggering exposure. Much still needs to be understood about this third wave of sensitivity.  

Another factor that influences a person’s sensitivity is the body’s reserve capacity. Researchers have speculated that a chemical exposure may affect the reserve capacity of the body without causing an immediate adverse effect. However, when there are subsequent exposures, the body becomes unable to compensate for the additional stress and toxicity develops.

The science behind what is known about how people respond to chemical exposures, especially to low level mixtures of chemicals, is highly complex and not well understood. We know that people exposed to low level mixtures of toxic chemicals, like the people in East Palestine, OH, the site of that horrific train derailment and subsequent intentional burn of vinyl chloride, continue to suffer adverse health effects despite reassurances from EPA and public health agencies who are relying on traditional toxicology and risk assessments. Perhaps the people in East Palestine have developed a unique chemical sensitivity much like the third wave described by Ashford and Miller. So as their exposures continue during the ongoing cleanup, their chemical sensitivity and the subsequent adverse health responses are not what would be predicted by traditional toxicology or medical models. 

This is an important consideration to consider in East Palestine because it is clear that we do not understand what is happening to the health of the people there. It’s time to recognize that we cannot rely solely on traditional toxicology to address the questions people have about exposures to low level chemical mixtures.

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Acrylonitrile

Toxic Tuesdays

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

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Acrylonitrile

Acrylonitrile is a clear liquid that smells like onions or garlic. It is man-made as it does not naturally occur on Earth. It is used to create other materials, most commonly acrylic fibers in clothing and carpeting. Acrylonitrile can enter the environment from industrial sites that produce it and waste sites where it is disposed of. Because it dissolves easily in water and readily evaporates, it can enter the water, air, and soil. Although acrylonitrile breaks down in water and soil, people can still be exposed to it if they live or work near factories that use it. They can also be exposed to it through acrylonitrile-based plastic products and acrylic fibers. In addition to industrial sources of exposure, acrylonitrile is also found in tobacco smoke and vehicle exhaust.

Inhaling airborne acrylonitrile can cause respiratory, skin, and eye irritation. It can also cause dizziness, headaches, weakness, impaired judgment, and, in extreme cases, convulsions. Exposure of acrylonitrile to the skin can cause burns and blisters, and repeated exposure can cause brain and liver damage. Studies on laboratory animals have also found that inhalation or oral exposure can cause low birth weights and birth defects.

The US Department of Health and Human Services, the US Environmental Protection Agency, and the International Agency for Research on Cancer have all determined that acrylonitrile probably causes cancer in humans. This is likely to occur through DNA damage. Research has found that people who work at facilities that use acrylonitrile have higher rates of lung cancer than the general population. Acrylonitrile is also one of the chemicals in tobacco smoke that is most associated with respiratory cancers. These findings demonstrate that acrylonitrile is dangerous enough that people need to be protected from it, especially if they live or work near facilities that use or dispose of it.

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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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The Future of Groundwater: A Fleeting Resource

Photo credit: https://www.britannica.com/science/groundwater

By Juliet Porter.

Climate scientists have discovered that Americans are using up groundwater faster than ever before in our history. Recently, the New York Times investigated this phenomenon by examining 84,544 monitoring wells, which trends have been examined since 1920. Approximately half of the wells examined have experienced decreasing water levels over the past 40 years as the rate at which water is being pumped out surpasses the water’s rate of replenishing.

In fact, from 2013 to 2023, ten of these wells reached their lowest water level ever recorded, with 2022 being the worst year on record. These statistics prompted the New York Times to further explore this issue by interviewing over 100 groundwater experts in the United States to inquire about the future of groundwater and its environmental justice implications of this crucial diminishing resource.

Drinking water in the United States originates from three major sources: surface water, reservoirs, and groundwater, which derives from aquifers, and recycled water, also known as reused water. Farming is a major source of groundwater usage. Thus, depleting groundwater not only affects public health but the economy as well. Vast, expansive farms and industrial cities are draining groundwater reserves. While groundwater is becoming increasingly unavailable, the rate at which it replenishes cannot keep up with demand. Unfortunately, drained reserves could take hundreds or even thousands of years to fully recover if they ever replenish at all. For this reason, depleting groundwater represents a serious threat that poses irreversible harm to our society. Simultaneously, rivers fed by groundwater are becoming streams, or nonexistent.

Disappearing groundwater has more adverse effects on certain states:

  • Kansas, a state that is a major aquifer that formerly supported 2.6 million acres of land, now is no longer capable of supporting industrial-scale agriculture;
  • New York, (Long Island) where the over-pumping of groundwater represents a threat to the longevity of drinking water wells;
  • Arizona, (Phoenix) which is one of the fastest-growing cities in America, currently there isn’t enough groundwater to build new houses that are reliant on aquifers; and
  • California, Utah, and Texas, also represent an overuse of groundwater and is causing roads to buckle, as foundations and fissures open-up.

Further exacerbating the issue of disappearing groundwater is the fact that there are little to no regulations addressing this topic. The federal government has shown that they have not addressed or played any role concerning this impending crisis. On the state level, there are few and far between rules on groundwater usage, and most of the existing laws are weak. In California, the Sustainable Groundwater Management Act was passed in 2014. This Act was intended to implement Groundwater Sustainability Agencies (GSAs) for each Basin by 2017 and integrate Groundwater Sustainability Plans by 2020 or 2022. However, in March 2023, it was found that the GSAs were falling behind on their sustainability goals. This lack of attention and lack of government intervention has fed the issue of depleting groundwater. This has enabled aquifer draining practices, (i.e. over-relying on groundwater in rapidly growing urban areas like Phoenix, Arizona, and planting water-intensive crops, like alfalfa, in drought prone areas).

At the end of the day, everyone’s environment is threatened because of the depletion of groundwater and the lack of access to safe, clean drinking water. Sadly, this issue affects disadvantaged communities at a higher rate, and resolving this issue will be no easy feat, as irreversible damage has already been done. The future of groundwater is expected to be continuously depleted in the coming years, and this issue will change America’s water systems’ future.

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Toxic Tuesdays

Asphalt VOCs

Toxic Tuesdays

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

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Asphalt VOCs

Asphalt is made of a compacted “aggregate” mixed with a “binder.” The aggregate takes the wear-and-tear of traffic while providing a nonskid surface. It comes from rock quarries, natural gravel, and/or soil. The binder is a type of cement that holds the aggregate together in place and provides waterproofing. It comes from the distillation of crude oil. To mix it with the aggregate, the binder is heated and thinned with other chemicals distilled from crude oil.

Some of these chemicals used to thin asphalt cement are classified as volatile organic compounds (VOCs), which are chemicals that contain carbon and readily evaporate into the air at room temperature. Common examples of VOCs include kerosene, chloroform, benzene, trichloroethylene, and perchloroethylene. Many VOCs are dangerous to human health. Inhaling air contaminated with VOCs can cause nose and throat irritation, headaches, nausea, and loss of coordination. Long-term exposure can cause more serious damage to the brain, liver, and kidneys. Some VOCs are also known to cause cancer in humans. Workers in facilities that make and mix asphalt are at the highest risk for health effects of exposure to VOCs. However, because VOCs diffuse through the air, people who live and work near these facilities could also be at risk.

VOCs aren’t only used in asphalt production; they’re also used in many industrial and commercial products. The US Environmental Protection Agency (EPA) estimates that VOCs are emitted by thousands of products. CHEJ has previously written about specific chemicals classified as VOCs: benzene, ethylbenzene, formaldehyde, trichloroethylene and perchloroethylene, toluene, and xylene.

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Water is the New Black Gold

Photo credit: Robert Ingelhart/Getty Images

By Sharon Franklin.

A recent New York Times series concerning fracking and water by Hiroko Tabuchi and Blacki Migliozziexplores the relationship between hydrofracking and our disappearing water sources.  

Giant new oil and gas wells that require astonishing volumes of water to fracture bedrock are threatening America’s fragile aquifers. An aquifer is a body of porous rock or sediment saturated with groundwater. Groundwater enters an aquifer as precipitation seeps through the soil. It can move through the aquifer and resurface through springs and wells. In Texas, the birthplace of the fracking revolution, increasingly complex oil wells are sweeping across the state into the surrounding United States. These new wells can consume millions of gallons of water that often come from our dwindling aquifers. To satisfy the “fracking thirst,” energy giants are now drilling not just for oil, but for the water they need to operate.

The New York Times series documents this surging water usage by examining an industry database in which energy companies report the chemicals they pump into the ground while fracking. The database includes details on their water usage, revealing the dramatic growth. Critics of fracking say it is an irony that so much water is being diverted to produce fossil fuels, given that the burning of fossil fuels is causing climate change, further straining freshwater resources. 

Nationwide, fracking has used up nearly 1.5 trillion gallons of water since 2011. This is equivalent to the amount of tap water used by the entire state of Texas in a year. Today, the insatiable search for oil and gas has become the latest threat to the country’s endangered aquifers, a critical national resource for industrial farming and cities. These mega-fracking projects, called “monster fracks,” have become the industry norm. They account for almost two out of every three fracking wells in Texas. Peter Knappett, professor of hydrogeology at Texas A&M University, refers to fracking companies as “newcomers, a new sector that burst onto the scene and is heavily reliant on the aquifers [that] could be pumping for several decades from aquifers that are already over-exploited and already experiencing long-term declines.”

There is public resistance emerging in New Mexico where a coalition of tribes and environmental groups are suing the state. They’re claiming that fracking companies are using up precious water resources and the state has failed to protect the interests of residents. Also, in Colorado, residents are fighting a proposed fracking project because they fear it would risk contaminating a reservoir their community depends upon. Oil companies require no permits to drill their own groundwater wells and there is no consistent requirement that groundwater used for fracking be reported or monitored. As droughts have gripped Texas and other Sunbelt states, many communities have instituted water restrictions for residents even as fracking has been allowed to continue unabated.

What is the oil industry saying about fracking?  Holly Hopkins, an Executive at the American Petroleum Institute, said the industry was “focused on meeting the growing demand for affordable, reliable energy while minimizing impacts on the environment” and its’ members were “continuing to develop innovative methods to reuse and recycle” water used for fracking. British Petroleum said it was “executing several pilot projects to recycle water” that would “minimize freshwater usage,” whileChevron added “that water was vital to its operations and that it aimed to use water efficiently and responsibly,” also saying that it used brackish or recycled water for fracking. Southwestern and Ovintiv did not respond to requests for comment.  

Because there is big money to be made in oil, and for those with access to water, it can be easy money to give away water rights. For example, Bruce Frasier, an onion grower who sells groundwater to a local fracking company for 50 cents a barrel, said that “If you’ve got the water to sell, you’re making a fortune”.   A small percentage of oil companies is making strides in reusing that fracking wastewater to drill for more oil and gas. Mr. Martin, a rancher and farmer who heads the Wintergarten Water District, doesn’t fault energy companies because he irrigates his cantaloupe fields using groundwater. However, he still contemplates a future of ever-dwindling aquifers, and somberly notes that “If the water goes away, the whole community will [go] away too.”

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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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Joppa, TX – Profile of a Sacrifice Zone

Photo credit: Nathan Hunsinger/The Dallas Morning News

By Hunter Marion.

Nestled between the slow, muddy waters of the Trinity River and the noisy I-45, sits Joppa, TX. Pronounced “Joppee” by locals, Joppa is a neighborhood located at Dallas proper’s southernmost point. It was founded by freed Black people shortly after the abolition of slavery in the 1870’s. Generations of residents lived relatively isolated from the growing metropolis until the town was annexed by the city of Dallas in 1955.

That annexation saw the gradual introduction of industrialization into the formerly forest-covered community. Pacific-Union built a railway cutting through the middle of the neighborhood. Asphalt plants, gravel mills, and landfills quickly ate up the bountiful, green floodplains of the area commonly called the “Bottoms.” Soon enough, Joppa became surrounded by polluting facilities and the refuse of interstate commerce.

Air pollution is the most prevalent problem affecting folks living in Joppa. Companies like Austin Industries, Martin Marietta, and TAMKO produce high amounts of particulate matter (PM) that consistently clog the lungs of locals. In the spring of 2023, air monitoring sensors in Joppa belonging to SharedAirDFW registered air quality that was double the EPA’s healthy standard of PM pollution!

Local organizations like Downwinders at Risk (a Dallas-based environmental organization and former CHEJ grantee) and Paul Quinn College have also reported that Joppa experiences levels of air pollution exceeding that of the rest of Dallas. Findings even cite that the life expectancy of Joppa residents is 13 years less than those living in the affluent Highland Park neighborhood of central Dallas. In addition to industrial contamination, the area is still recovering from the presence and removal of a giant pile of shingle debris called “Shingle Mountain,” which contributed to long-term water and air contamination in Joppa and the nearby neighborhood, Floral Farms.

To combat this issue, Joppa residents have been steadily gaining media attention and political action through grassroots efforts. For instance, in early 2023 residents sought to block the renewal of Austin Bridge & Road’s 10-year “specific-use” permit and protested the presence of a concrete batch plant that was discovered to be in operation without a permit. Local leaders like Alicia Kendrick have been vocal about the industries harming their homes, families, and friends, especially complaining about the EPA and Texas Commission on Environmental Quality’s (TCEQ) lack of enforcement on air quality standards in the area.

A key development in the fight to protect the neighborhood has been the Joppa Environmental Health Project. This is a community-led three-year environmental health study overseen by a research group from Texas A&M University. The project focuses on the effects of PM exposure upon Joppa’s residents. Community members intend to use the findings from this project as leverage against the city council to wrest control of Joppa over from the polluters. Although companies like Austin Industries have been prioritized by Dallas’s city council in the past, Kendrick and others have hope that continued pressure from organizing and research will prevail. They did not have to wait too long for a victory.

In June 2023, the Austin batch plant officially announced its closure and removal from the community. Excited by the victory of her 14-month battle against the company, Kendrick said that she was “determined to see this through, to use this [win] as a first step in giving Joppa residents a neighborhood where the air is safe to breathe.”