• Air monitoring trends and data

    MassDEP has monitored some pollutants for more than 20 years. Find summaries of long-term historic data here.
  • Air pollutants fact sheets

    Acid rain, carbon monoxide, haze, lead, nitrogen dioxide, ozone, particulate matter, sulfur dioxide, and toxics are all pollutants. Check these air fact sheets to learn about what each pollutant is and where it comes from, health and environmental effects, standards and long-term trends, and more.
  • Air quality alert program

    Air Quality Alert Program for New England.
  • Air quality and monitoring

    Wondering how clean or polluted the air is in your part of Massachusetts, and what it might mean for your health? Here you can access the Daily Air Quality Forecast, download data for research, obtain pollution reports and studies, select from a variety of air pollutants, locations, and time periods to develop custom graphs showing emission trends over time, Learn about the Department of Environmental Protection's statewide ambient air quality monitoring network.
  • Air quality forecast

    The Department of Environmental Protection provides a daily ozone forecast from May through September and a daily fine particle forecast all year round.
  • Air quality index

    Hourly air quality index from the United States Environmental Protection Agency.
  • Air toxics links to PDF file

    Toxic air pollutants, also known as hazardous air pollutants, are those pollutants that are known or suspected to cause cancer or other serious health effects, such as reproductive effects or birth defects, or adverse environmental effects. Learn more about the effects of toxic air pollutants, where they come from, what is being done to control air toxic pollutant emissions in Massachusetts, and more.
  • Current pollution levels

    Check the daily air quality forecast and current pollution levels, sign up for air quality alerts, learn about good and bad ozone, particle pollution, health effects of pollution, and more.
  • Fine particles in Massachusetts communities

    Fine particle pollution in the air comes from local, regional, national and even global sources -- primarily fuel combustion, road dust, and fires. Find out what affects particle pollution levels, and what pollution levels are within your community.
  • Ground-level ozone

    Ground-level ozone: what it is, health effects, environmental effects, standards, and long-term trends.
  • Health effects of air pollution links to PDF file

    Air pollution can harm us when it accumulates in the air in high enough concentrations. Millions of Americans live in areas where urban smog, particle pollution, and toxic pollutants pose serious health concerns. Learn who is most at risk and the health effects of common air pollutants.
  • Indoor air quality

    Check out these indoor air quality assessments conducted in public schools, courthouses, town halls, libraries, and other public buildings to learn what's being done to improve indoor air quality.
  • Air and climate laws, regulations, and policies

    Gases, particles and toxics in the air we breathe can harm our lungs and threaten our health. The Department of Environmental Protection is working continuously to reduce the risks posed by air pollution and climate change. Find regulations, standards, policies, and environmental laws on air and climate here.
  • Ozone in Massachusetts communities

    Ground-level ozone pollution, or smog, tends to be at its worst in the summer and later in the day, when the conditions required for its formation are most prevalent. Learn about the monitoring devices the Department of Environmental Protection has in place to measure air concentrations of ozone and report on air quality in your community and region.
  • Particle pollution

    Particle pollution (also known as "particulate matter" or PM) includes a mixture of solids and liquid droplets. Some particles are emitted directly; others are formed in the atmosphere when other pollutants react. Particles come in a wide range of sizes.
  • Radon links to Word file

    Radon is an odorless, radioactive gas formed from the breakdown of uranium and thorium. Exposure to high levels results in an increased risk of lung cancer. Here you'll find a fact sheet with helpful information regarding radon, and corrective actions should it be present in the air and water in your home.
  • Transportation, fuels, and air quality

    Motor vehicles, engines, and fuels are among the leading contributors to air pollution in Massachusetts. Each of us can make a difference in the quality of the air we breathe by driving clean-running and fuel-efficient vehicles, keeping them well maintained, and making smart commuting choices.
  • U.S. EPA regulations and statues

    A number of laws serve as the Environmental Protection Agency’s (EPA's) foundation for protecting the environment and public health. However, most laws do not have enough detail to be put into practice right away. EPA is called a regulatory agency because Congress authorizes EPA to write regulations that explain the critical details necessary to implement environmental laws. In addition, a number of Presidential Executive Orders (EOs) play a central role in EPA activities.