EDF Health

Cumulative assessment better estimates the real-world risks chemicals pose on our health

By Paige Varner, PhD, Scientist, Healthy Communities / Published: August 13, 2024
NOTE: This is the second of a series about EPA’s prioritization of existing chemicals. 

What Happened? 

EPA just proposed to designate five chemicals, including the widely-known toxic chemical vinyl chloride, as high-priority chemicals – meaning they are toxic to human and/or environmental health.  If finalized, these chemicals will immediately undergo the risk evaluation process under the Toxic Substances Control Act (TSCA).  

When designating these chemicals as high priority and moving forward in assessing their health risks, EPA can – and should – consider exposures to multiple chemicals that can cause the same health harms. To demonstrate the importance of these cumulative exposures, we conducted analysis on co-exposures to these five chemicals and submitted this analysis to EPA for greater consideration of real-world risks faced by individuals exposed to these toxic chemicals.  

Why It Matters 

Communities near industrial facilities are often exposed to multiple chemicals that cause the same health effects. Evaluating the health risk of these chemicals individually, as currently done by EPA’s TSCA program, often underestimates the true risks communities face. Additionally, many of these fenceline communities experience a variety of non-chemical stressors that exacerbate health effects from chemical exposure, such as physiological stress from poverty and racial discrimination, limited access to healthcare, or health effects from climate stressors like flooding and heat. Failing to consider these cumulative stressors on health in chemical risk evaluations often underestimates the actual risks these chemicals can pose to human health.  

Our Take 

Our analysis of Toxics Release Inventory (TRI) data from 2016-2021 shows that many chemicals that cause the same health effects – such as cancer, central nervous system (neurological), cardiorespiratory, liver, kidney, and thyroid, and reproductive and developmental effects – are often released together from the same facilities. For example, chemicals that cause cardiorespiratory effects are released with at least one other chemical that causes these same effects 74% of the time.  

For the five chemicals that have just been proposed as high priority under TSCA, all are known or probable carcinogens with some causing other adverse health effects. Based on our analysis, there are a few notable co-releases that EPA should consider when assessing cumulative risk with other chemicals causing the same harms. For example, creosotes, which are also probable carcinogens that can cause liver, kidney, and thyroid effects, are released 11% of the time with acrylonitrile, 18% with aniline, 11% with vinyl chloride, and 11% with 4,4-methylene bis(2-chloroaniline). 

Screenshot - Heatmap of co-releases of carcinogenic chemicals that are part of the TSCA Workplan.

Heatmap of co-releases of carcinogenic chemicals that are part of the TSCA Workplan. Legend represents the percentage of facilities releasing both chemicals out of the facilities releasing at least one of the pair of chemicals. Stars represent the 15 chemicals that were considered as part of TSCA’s pre-prioritization.

To demonstrate that EPA should also consider non-chemical stressors such as climate and environmental justice in its TSCA prioritization and risk evaluations, we looked at the vulnerability of communities to climate and environmental justice factors in areas where certain chemicals are released using EDF’s Climate Vulnerability Index. On average, vinyl chloride is released into communities with higher vulnerability than other chemicals analyzed – up to 12% higher than the average for other carcinogenic chemicals.  

What’s Next? 

EPA is now accepting comments on their proposal to designate these five chemicals as high priority, and we plan to submit comments to support the high priority designation. If finalized, EPA will begin risk evaluations for these chemicals. We hope EPA will consider cumulative risk and environmental justice as it moves through this process.   

In our next post in this series, we will recommend ways EPA can improve its prioritization process by considering risks from transportation and distribution of chemicals. 

Also posted in Adverse health effects, Chemical exposure, Chemical regulation, Cumulative risk assessment, Environmental justice, Health policy, Public health, Regulation, Risk assessment, Risk evaluation, Rules/Regulations, TSCA, TSCA reform, Vulnerable populations / Authors: / Comments are closed

Unveiling EDF’s Chemical Exposure Action Map

By Maria Doa, PhD, Senior Director, Chemicals Policy and Paige Varner, PhD, Scientist, Healthy Communities / Published: February 22, 2024

U.S. map showing chemical facilities across the nationWhat’s New

Today, we are excited to introduce the Environmental Defense Fund’s (EDF) latest initiative—the Chemical Exposure Action Map. This tool is designed to spur the Environmental Protection Agency (EPA) to transform the assessment of risks posed by toxic chemicals in our communities.

Our map focuses on multiple high-priority chemicals—making visible the urgent and long-overdue need to assess the risks of chemicals together as they exist in the real-world. Unlike many current methods that look at risks one chemical at a time, our map offers a comprehensive view, highlighting the potential for cumulative risks from multiple high-priority chemicals.

Why It Matters

In a world where industrial facilities expose communities to multiple harmful chemicals daily, many have long called for a cumulative approach to assessing the risks from these chemicals. It is crucial that we wait no longer to reassess how we evaluate the health risks they pose.

Pregnant Latine woman gazing lovingly at young daughter who is hugging her belly.

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Also posted in Adverse health effects, Carcinogenic, Chemical exposure, Chemical regulation, Cumulative risk assessment, Developmental toxicity, Health hazards, Health policy, Public health, Regulation, Risk assessment, Risk evaluation, TSCA, Vulnerable populations / Tagged , , , , , , | Authors: , / Comments are closed

Now’s the Time—How EPA can use TSCA to turn off the PFAS tap

By Maria Doa, PhD, Senior Director, Chemicals Policy / Published: September 18, 2023

Faucet with the word PFAS flowing out of it

In the face of mounting evidence about the dangers posed by per- and polyfluoroalkyl substances (PFAS), one thing is clear: EPA needs to take urgent action to turn off the tap of these “forever chemicals” that have long-term consequences for our health and the environment.

As we discussed in a previous blog, it is imperative that the Environmental Protection Agency (EPA) use the Toxic Substances Control Act (TSCA) to regulate PFAS chemicals comprehensively—both those newly entering the market and those that have been in circulation for decades.

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Also posted in Chemical exposure, Chemical regulation, Cumulative risk assessment, Drinking water, Emerging science, Health policy, Public health, Regulation, Risk assessment, Risk evaluation, TSCA, TSCA reform, Vulnerable populations, Worker safety / Tagged , , , | Authors: / Read 2 Responses

EPA’s approach to 1,4-dioxane falls short of protecting fenceline communities

By Maria Doa, PhD, Senior Director, Chemicals Policy and Paige Varner, PhD, Scientist, Healthy Communities / Published: September 14, 2023

Clear water pouring from a pitcher into a glass.What’s New?

Recently, the Environmental Protection Agency (EPA) embarked on a critical Toxic Substances Control Act (TSCA) supplemental risk evaluation of 1,4-dioxane [PDF, 8.7MB]– a highly carcinogenic chemical that contaminates drinking water supplies across the country and is present in products, such as cleaning supplies and personal care products.

This draft supplemental risk evaluation represents a significant step forward because it addresses many of the omissions from the original 1,4-dioxane risk evaluation. Unfortunately, as we noted in our comments to EPA, a closer examination reveals several shortcomings in how EPA addresses risks to fenceline communities—people living, playing, and working near industrial facilities that release toxic chemicals into the air and water. Read More »

Also posted in Chemical exposure, Chemical regulation, Cumulative risk assessment, TSCA / Tagged , , | Authors: , / Read 1 Response

New guidelines to inform EPA’s approach to cumulative risk

By Paige Varner, PhD, Scientist, Healthy Communities / Published: September 12, 2023

What’s New?

The Environmental Protection Agency (EPA) recently released and solicited public comments on its draft Cumulative Risk Assessment (CRA) Guidelines for Planning and Problem Formulation. The purpose of a CRA is to determine the combined health and/or environmental risks from multiple stressors and chemicals that can cause the same harms. These guidelines, intended to be applied to all of EPA’s programs and regions, describe how the agency will determine when to use CRAs and the steps it will take to plan them.

Why It Matters

Currently, many EPA programs assess the health and environmental risks of single chemicals, without considering the multiple chemicals that cause the same harms and non-chemical stressors we are exposed to every day. Assessing risks cumulatively, and making regulatory decisions based on this, represents real-world exposures more accurately than single-chemical stressor risk assessments. Read More »

Also posted in Chemical exposure, Cumulative risk assessment, Health policy, Public health, TSCA, Vulnerable populations / Tagged , , | Authors: / Comments are closed

EPA Should Use U.S. Chemical Safety Law to Turn Off PFAS Tap

By Maria Doa, PhD, Senior Director, Chemicals Policy / Published: June 30, 2023

The word

PFAS is a group of synthetic chemicals used in industrial processes and consumer products, including water-repellent clothing, such as outdoor wear, and food packaging. Once these “forever chemicals” are produced and used, they often make their way into the environment and our bodies. Many pose serious threats due to their toxic effects (often at trace levels) and their ability to build up in people, animals and the environment. Studies show that they are in almost all of us.

To make matters worse, people are exposed to multiple PFAS, not individual PFAS in isolation. Yet under the nation’s primary chemical safety law, EPA evaluates the safety of PFAS chemicals one at a time and does not consider the combined risks from exposures to multiple PFAS. Combined exposures increase the risk of harmful effects, thus magnifying the risks and the need for action.

Current Situation: All Costs, No Benefits

PFAS move easily throughout the environment and are difficult to destroy. They have contaminated drinking water, food, farms, wildlife, and the environment more broadly. At the local, state and federal levels, the U.S. is spending millions of dollars to clean up PFAS contamination. Some states, such as Michigan and Maine, are trying to recoup the costs their residents have had to bear to clean-up PFAS contamination of their water and land. The federal government is also taking action to address the widespread PFAS contamination. The costs for cleaning up PFAS contamination are imposed on society by the domestic producers, importers and users of PFAS who profit from their production and use.

Yet, despite the well-documented risks and costs to society of these chemicals, companies still continue to produce, import, and use PFAS. It is time to ban all PFAS or—if there are truly essential uses for these chemicals—limit how they are produced, imported and used so that their impact on us and the environment is minimal.

Urgent Need: Revisit, Reassess, and Regulate All PFAS

While EPA has recently tightened up approvals for new PFAS entering the market, it has yet to take significant action on those that are already on the market, which includes the hundreds of PFAS the agency approved over the past few decades. It is clear these PFAS have not been produced responsibly as demonstrated by the environmental contamination associated with many of the PFAS manufacturing facilities. And yet, many of these PFAS are still on the market. They are being produced and released into the environment, are in products we use every day, and continue to contaminate us and our environment.

Many of EPA’s approvals were made 10 to 20 years ago, before we had a full picture of the pervasiveness and degree of PFAS contamination. The data on the extent of the environmental contamination of these persistent PFAS, their ability to move through the environment, and the significant difficulty in destroying them was not as robust as it is today. Furthermore, mounting evidence shows that even trace levels of PFAS can cause developmental issues in children, reduced fertility, hormonal disruptions, and certain types of cancer.

In addition, these approvals did not consider risks to vulnerable groups, such as pregnant women and children as currently required by the law. Many communities are exposed to multiple PFAS, particularly those who live, work and play near where PFAS are made and used.

Addressing the production, import and use of PFAS would limit further pollution of our water supplies, safeguard the health of our communities, and be consistent with other strong EPA actions to address PFAS, including its recent robust proposed drinking water standards.

Effective regulation of these harmful chemicals at their source would also accelerate efforts to seek out and adopt safer alternatives. Leaving chemicals with such well-documented harms on the market makes it more difficult for innovative, safer substitutes to enter it. Failing to address these risks in effect puts a thumb on the scale in support of older harmful technologies.

Our Take

EPA should re-evaluate each of the PFAS it has approved. During that re-evaluation, EPA should use the best available science and consider the full picture of PFAS exposure. Considering each PFAS in isolation rather than the multiple PFAS people, particularly those in vulnerable groups, are exposed to will underestimate their risk.

EPA should use the Toxic Substances Control Act to take action to ban these legacy PFAS, or restrict them if the uses are truly essential, rather than continuing to allow the production, import and use of these demonstrably harmful “forever chemicals.”

Go Deeper

Learn more about EDF’s concerns about PFAS and read our follow-up blog  on how EPA can use TSCA to turn off the PFAS tap.

EPA’s information on PFAS

Also posted in Chemical exposure, Chemical regulation, Contamination, Cumulative risk assessment, Emerging testing methods, Food, Food packaging, Health hazards, Health science, Public health, Risk assessment, Risk evaluation, TSCA, Vulnerable populations / Tagged , , , , , , , , , , , , | Authors: / Comments are closed