Environmental Public Health Tracking: Toxic Air Emissions Data

Wisconsin Tracking hosts data on toxic air emissions in Wisconsin.  When an industry releases air that is potentially cancer-causing (carcinogenic) or possibly unsafe for our health, its release is reported to both the state and federal government.  

Industries that release these emissions above certain levels report the amount released each year to the Wisconsin Department of Natural Resources (DNR). We get our data directly from the DNR.

Access the toxic air emissions data

Visit our air quality data page for more information about the air pollution data we host.  To learn more about other types of air pollution, visit the air quality issues page.

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What are toxic air emissions?

Emissions are substances released into the air.  The data we host reflect emissions from stationary industrial activities such as manufacturing.  When emissions have the potential to cause harm to humans, they are called toxic air emissions. 

How do people come in contact with toxic air emissions?

We can come in contact with toxic air emissions by breathing in polluted air or breathing in polluted dust particles.

What are the health effects of toxic air emissions?

We host data on emissions that are associated with a variety of health issues, including cancer.   However, the level of exposure and length of time needed to cause cancer are not fully understood. It is likely that for most people environmental factors – such as emissions – play a smaller role in cancer than other factors, such as genetics and personal behaviors, but emissions are still an important risk to consider.

Scientists estimate between 4% and 19% of cancers are related to environmental factors. Breathing problems, kidney failure, heart failure, infertility, and birth defects can also result from coming in contact with emissions. Finally, factors often work together to increase risk. For instance, genetics, personal behavior, and environmental factors could all increase an individual’s risk of cancer.  Social determinants of health also play an important role; for example, low-income communities and communities of color are more likely to face environmental hazards such as living close to a factory.  

What can people do to protect themselves from toxic air emissions?

The Wisconsin Department of Natural Resources (DNR) and the United States federal government are all responsible for enforcing toxic air emission laws that help keep us safe.  You can also take steps to protect yourself and your family by learning more about specific pollutants and their levels around areas where you live, work, and play. The Wisconsin DNR also has more information on air quality.

Which measures does Wisconsin Tracking have for toxic air emissions?

All toxic air emissions data come from the Wisconsin Department of Natural Resources.  Under Wisconsin Administrative Code NR 438.03 (Air Contaminant Emissions Inventory Reporting Requirements), industrial facilities in Wisconsin must report air contaminant emissions when emissions exceed reportable levels.  The list of the 37 emissions for which we have data are below, and you can learn more about each of these emissions on our data details page.

  • Acrolein
  • Acrylonitrile
  • Ammonia
  • Arsenic
  • Benzene
  • Benzidine
  • Beryllium
  • 1,3-Butadiene (Butadiene - 1,3)
  • Cadmium
  • Chlorine
  • Chromium (Metals and Other)
  • Chromium (VI)
  • Ethanolamine
  • Ethylbenzene
  • 2-Ethoxyethanol
  • Ethylene Oxide
  • Formaldehyde
  • Hydrogen Sulfide
  • Lead
  • Mercury (Alkyl)
  • Mercury (Aryl)
  • Mercury (Inorganic Forms)
  • Methylene Chloride
  • Naphthalene
  • Nitric Acid
  • Perchloroethylene (PERC)
  • Phenol
  • Phosphoric Acid
  • Stoddard Solvent
  • Styrene (Monomer)
  • Sulfuric Acid
  • Tetrachlorodibenxo-p-dioxin-2,3,7,8 (TCDD)
  • Toluene
  • Trichloroethylene
  • Triethanolamine
  • Vinyl Chloride
  • Xylene

Can I use Wisconsin Tracking data to see if I have been exposed to toxic air emissions?

Measuring the link between disease and toxic air emissions is a complex issue. The data we host are based on reports of emissions received by DNR. The numbers we list on the portal are of the amount of the compound released into the air during the year it was reported. Emissions mix with air and are diffused over time. Given wind and weather patterns, it is not possible to use this data to estimate direct exposure. As such, the data we host cannot be used to look for direct links between cancer and the environment. Instead, toxic air emission information is one of the many pieces of data that helps us assess population-level disease risks.

Where can I find permit information for facilities reporting emissions in my county?

The Wisconsin DNR hosts an Air Management Data Viewer which allows you to view all facilities and their permit information.

Where can I learn more about each toxic air emission?

Visit the toxic air emissions tab on our data details page.  Under each type of emission, we linked the CDC webpage with more information.  To learn more about the Wisconsin Air Toxics Rule (NR 445), visit the DNR website.

Last Revised: September 8, 2021