Hazard and Risk-Screening Trend
Hazard Trend
RSEI Hazard, also called toxicity-weighted pounds, is a descriptor of relative potential harm to human health. It is based on the toxicity of a chemical and the quantity of the chemical released into the environment. Weighting releases based on toxicity gives greater significance to more toxic chemicals and more context than the release quantities alone. The following graph shows the 10-year trend in calculated RSEI Hazard compared to the trend in the unweighted quantity of chemicals used to calculate RSEI Hazard (corresponding pounds).
Note: For comparability, trend graphs include only those chemicals with toxicity weights. RSEI Hazard values and corresponding pounds include only on-site air releases, on-site water releases, transfers to publicly owned treatment works (POTWs), and transfers to incineration.
From 2013 to 2022:
- The calculated RSEI Hazard values shown in the figure above decreased by 22%, while the corresponding release quantities (in pounds) decreased by 12%. This suggests that TRI facilities are not only releasing or transferring fewer pounds of TRI chemicals for these activities, but are also releasing fewer pounds of the more toxic TRI chemicals.
- The largest decreases in RSEI hazard were from ethylene oxide, chromium, arsenic compounds, chloroprene, and polycyclic aromatic compounds.
Risk-Screening Trend
RSEI Scores are indicators of relative potential risk to human health and are intended for use in comparative analysis. RSEI Scores consider the locations and quantities of TRI chemical releases as well as the number of people living in the surrounding areas. The scores also account for what happens to the chemical in the environment, where it might go, and how much of the chemical people might be exposed to.
The following graph shows the 10-year trend in calculated RSEI Score compared to the trend in the corresponding pounds of TRI chemicals released or transferred that are used to calculate the RSEI Score.
Note: RSEI Score values and corresponding pounds include only on-site air releases (Air Releases), on-site water releases (Water Releases), transfers to POTWs, and transfers to incineration.
From 2013 to 2022:
- The overall calculated RSEI Score decreased by 24%, while corresponding release quantities (in pounds) decreased by 12%. This suggests that TRI reporting facilities are: releasing or transferring fewer pounds of TRI chemicals; releasing fewer pounds of the more toxic TRI chemicals; or that releases are occurring in areas that are less populated.
- While RSEI Score does not describe actual risks to human health from TRI chemicals, the overall decrease in RSEI Score indicates that, at the national level, the relative potential risk from toxic chemicals reported to TRI has declined from 2013 to 2022.
- Of the types of releases modeled by RSEI, air releases contribute the most to potential human health risks based on calculated RSEI Scores.
- The decrease in RSEI Score from 2013 to 2022 was driven in part by large decreases in air releases of ethylene oxide and chromium and chromium compounds.
RSEI Dashboard
- Use EPA's EasyRSEI Dashboard to view the national trend in RSEI Hazard and RSEI Score, or use the Dashboard’s filter capabilities to view other RSEI information for a specific chemical or location of interest.
This page was published in March 2024 and uses the 2022 TRI National Analysis dataset made public in TRI Explorer in October 2023.