The PBT Profiler is an online risk-screening tool that predicts a chemical's potential to persist in the environment, bio-concentrate in animals, and be toxic, properties which cause concern for human health and the environment. PBT stands for Persistence, Bioaccumulation and Toxicity. More information on PBT chemicals can be found on EPA's PBT Web site.
Basing its assessment on a chemical's structure, the PBT Profiler determines if a chemical is expected to exceed the PBT criteria under EPA's New Chemicals Program and/or Toxic Release Inventory (TRI). The PBT Profiler can also tell the user if the chemical belongs to a category that is known to present human health concerns as described in EPA's Chemicals Category Report.
The PBT Profiler was beta tested, peer reviewed, and released to the public in September 2002. The PBT Profiler Peer Review can be obtained online at www.regulations.gov by searching "all documents" for key word "PBT Profiler."
The PBT Profiler was developed by EPA through a collaborative effort with the chemical industry and Environmental Defense. It was developed to be a voluntary screening tool to identify pollution prevention opportunities for chemicals without experimental data.
Information Needed to Use the PBT Profiler
Before you run the PBT Profiler you should:
- Establish if measured data exist on the persistence, bioaccumulation, and toxicity of your chemical (measured data are preferred over screening-level estimations);
- Determine the structure of the chemical you want to profile; and
- Determine if your chemical is appropriate for evaluating with the PBT Profiler. For technical reasons there are chemicals that should not be profiled using the PBT Profiler, and users should check the online information on the method's Web site before evaluating a chemical.
How to Use PBT Profiler Predictions
The PBT Profiler is best used as a research tool to identify chemicals that may need further evaluation for potential persistence, bioaccumulation and toxicity. The PBT Profiler is a screening-level method that, like all screening methods, has certain limitations . If the chemical being evaluated is identified as a potential PBT, the user should conduct further evaluations of the chemical.
These evaluations can include:
- Verifying chemical composition (including structure)
- More extensive data searches
- Estimations using other methods
- Estimation of possible releases to the environment and any resulting exposures
- Comparing the estimated results with a data-rich chemical that has a similar structure
If testing to confirm estimations is necessary EPA has information on Harmonized Test Guidelines. Consultation with a scientist who can assist with these evaluations may be helpful.
For Community Groups and the Public
Community groups and the general public can use the PBT Profiler to estimate the PBT potential of chemicals lacking data. The PBT Profiler can also identify pollution prevention (P2) opportunities and help groups make informed decisions on which chemicals may be a concern.
After running a chemical through the PBT Profiler, the user can click on "P2 Considerations" on the bottom of the "Results" page to get useful information on how the chemical is predicted to behave if released to air, water, or soil. General users are encouraged to work with scientists (chemists, toxicologists, or risk assessors) to be sure the method is used properly and results are interpreted properly.