North Carolina industry released the least amount of air pollution last year — 21.5 million pounds — since 2003, according to federal data released last week. Releases to land were also at 16-year lows, but discharges to waterways — 8.1 million pounds — were the highest since 2015.
Releases for air, land and water totaled 39 million pounds.
The Toxics Release Inventory, administered by the EPA, collects data from industrial facilities for 770 chemicals. There are some data shortcomings : Not all toxic chemicals are included in the TRI and the data is self-reported. Nonetheless, the inventory can inform people about significant polluters in their communities. The reportable chemicals include those that can cause cancer or other chronic human illnesses; significant adverse acute human health effects and environmental harm.
The TRI lists all reporting facilities and their releases by state, Zip code, city or county. You can also search by facility, industry, and chemical. (Frankly, the website is a rabbit hole where you can get lost for hours.) To help, the EPA offers an instructional video  on how to navigate the database. I’ve also laid out a step-by-step beginners’ guide  to gleaning the information.
Here are some summary data for North Carolina. All figures are for 2019, except where noted.
17 — Rank of North Carolina among 56 states and territories, in amount of pollutants released to the environment
762 — Number of facilities in North Carolina required to submit TRI reports to the EPA
58 — Number of facilities in Mecklenburg County, which has the most in the state
190,942 — Pounds of pollutants released in Mecklenburg County
55 — Number of facilities in Guilford County, which ranks second in the state
233,187 — Pounds of pollutants released in Guilford County
39 million — Pounds of pollutants released by all industries, onsite
21.5 million — Pounds released into the air
9.3 million — Pounds released onto the land
8.1 million — Pounds released into the water
17.9 million — Pounds of additional pollutants shipped offsite for treatment, recycling or disposal, all industries
5.13 million — Pounds of pollutants released by PCS Phosphate, in Beaufort, which ranks first in all releases to the environment in North Carolina
4.81 million — Pounds of pollutants released by CPI, an electric utility in Southport, which ranks second
3.23 million — Pounds of pollutants released onsite by Smithfield Tar Heel slaughter plant, in Tar Heel, which ranks third
127 million — Pounds of pollutants released by industries onsite, 2005, the largest amount in the past 15 years
Source: EPA Toxics Release Inventory, 2019