Determination of Pitch Volatiles in Airborne Partieulates

The benezene-Soxhlet extraction determination of pitch volatiles collected with personnel samplers is shown to be an inaccurate procedure. At present, results are calculated from the weight loss of filters on extraction. In reality, they reflect mechanical losses of filter media and particullate. In addition, plasticizers in certain cassettes are adsorbed onto the filters and are subsequently extracted, which partially explains the high blank values associated with the method. This paper summarizes the experimental evidence supporting these conclusions and provides a basis for the development of an acceptable analytical method.