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Archive for September, 2012

PAH Analysis: Expanded Compounds of Concern and Advancements

Wednesday, September 5th, 2012

By Lee Wolf, Regulatory Affairs Manager, ALS Environmental – USA

As a class of organic compounds, PAHs are characterized by bonded aromatic rings that do not typically carry other functional groups or branched groups substituted for hydrogen atoms. PAHs occur in fossil fuel materials such as oil, coal, tar and fuels. They are produced as a result of fuel burning. They are also found in products such as burned tobacco, incense, and some plant-based oils. To further understand the sources of PAHs, they may be classified as follows:

  • Petrogenic – These are PAHs derived from petroleum inputs and generally associated with fossil fuels.
  • Pyrogenic – These are PAHs which are derived from combustion sources.
  • Biogenic – These are PAHs formed from natural biological processes.

The toxicity of PAHs is dependent upon the structure or arrangement of aromatic rings. For example, the toxicity of some PAH isomers (with the same formula and number of rings) can vary from being effectively nontoxic to being very toxic. The more toxic or carcinogenic PAHs may be small or large. The USEPA has identified seven PAH compounds as probable human carcinogens.

Read more about PAH Analysis…