Use for Polynuclear Aromatic Hydrocarbons (PAH) or other semi-volatile compounds in ambient air or other gas samples.
Samples are collected by drawing a large volume of air through a Polyurethane foam (PUF) cartridge. For a high pollution level area, low volume sampling may be required. For high volume sampling a total of 2-20 m3 of air should be sampled. For a low volume sampling 5-50 liters of air should be sampled.
The sample is extracted by the Soxhlet method using methylene chloride followed by Kuderna-Danish concentration of the extract. The extractant of the sample is analyzed by GC/MS. Other solvents may be substituted for the methylene chloride used in the extraction. For example, hexane plus dimethyl ether, depending on what kind of target compounds, are of interest.
PUF cartridge, GC/MS, Soxhlet extractor, Kuderna-Danish concentrator
For most compounds, a detection limits of 1.0 ppbv may be obtained.
Lower detection limits can be achieved by this method. GC/MS can identify most semi-volatile compounds.
Both sampling and analysis are complex techniques. Extraction and analysis are lengthy.
If GC/MS is not available, HPLC may be used for analysis.
Stack gases from incinerators, manufacture emission gas surveys, ambient air monitoring.