The PBT Profiler requires a chemical name and ID Number for each chemical profiled. The preferred ID number is a chemical's CAS Registry Number, although the PBT Profiler will accept any combination of letters, characters, and numbers as an identifier. Chemical names can be in any format up to 120 characters in length.
The PBT Profiler predictions are determined using structure-based estimation methods. The chemical structure of the chemical you want to profile is, therefore, required in order to use the PBT Profiler. The chemical structure is entered into the PBT Profiler by using its SMILES notation, a line-entry system based on elemental symbols.
For those unfamiliar with SMILES notation, online help is available. A SMILES notation can also be generated using the export feature available on many commercial chemistry drawing programs. If you have a chemistry drawing program on your PC, you can "copy" the SMILES notation and "paste" it into the PBT Profiler.
The PBT Profiler has a number of features to help users enter their chemical structure. A lookup database, based on a chemical's CAS Registry Number, contains SMILES notations for over 100,000 chemicals. Note: some of the chemicals in the lookup database have experimental data available and should not be profiled. The PBT Profiler also contains a structure drawing interface that does not require any plug-ins or add-ons. This interface automatically converts a chemical structure (drawn on the web page) to its SMILES notation.General Chemical Information
Users are required to have general information on the nature and reactivity of their chemical to establish if it can or cannot be profiled. Chemicals that rapidly hydrolyze or are highly reactive cannot be profiled. Chemicals that have a high molecular weight (>1,000), are of unknown or variable composition, or contain any metallic elements also cannot not be profiled. More information on why these chemicals should not be profiled is available.
The PBT Profiler is designed for discrete organic chemicals although many chemical products and feedstocks are a mixture of closely related compounds. Mixtures cannot be evaluated using the PBT Profiler. A single, discrete organic compound representative of the mixture may be used although the results should be interpreted with great caution. Representative components of a mixture should only be profiled after an expert familiar with environmental fate and toxicity relationships has been consulted. Assistance is available from the developers of the PBT Profiler.
Developed by the
Environmental Health Analysis Center under contract to
Office of Chemical Safety and Pollution Prevention
U.S. Environmental Protection Agency
Computer Resources Donated by SRC, Inc. Ver 2.000 Last Updated September 4, 2012