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TRI National Analysis

Air Releases by Chemical & Industry

Air Releases By Chemical

This pie chart shows which TRI chemicals were released to air in the greatest quantities during 2019.


Note: Percentages do not sum to 100% due to rounding.

  • Facilities that manufacture nitrogen-based fertilizers accounted for more than one third of the quantities of ammonia released to air, as reported to TRI for the past eight years.
  • Releases of methanol to air were primarily from facilities in the paper manufacturing sector and have decreased by 26% since 2007.
  • Air releases of n-hexane were primarily from food manufacturing facilities. Air releases of n-hexane have increased by 6% since 2007.
  • In 2019, 79% of sulfuric acid and 29% of hydrochloric acid emissions to air were reported by facilities in the electric utilities sector. The quantities of these two chemicals released to air by electric utilities have decreased considerably since 2007. One reason is the increase in the use of natural gas as a fuel for electricity generation. Power plants that combust only fuels other than coal or oil, such as natural gas, are not required to report to TRI.

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Air Releases By Industry

This pie chart shows the TRI-covered industry sectors that reported the largest releases of TRI chemicals to air during 2019.


Note: Percentages may not sum to 100% due to rounding.

  • The chemical manufacturing, paper manufacturing, and electric utility sectors accounted for the largest releases of TRI chemicals to air during 2019, although air releases of TRI chemicals by these industries have decreased since 2018:
    • Chemical manufacturing: 2.2 million pound decrease (-1%)
    • Paper manufacturing: 4.1 million pound decrease (-3%)
    • Electric utilities: 10.5 million pound decrease (-13%)

This page was published in January 2021 and uses the 2019 TRI National Analysis dataset made public in TRI Explorer in October 2020.

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