Blank values of 30 elements in 19 filter materials determined by ICP-MS.

The blank values of 30 elements in 19 different filter types from Gelman, Millipore, Nuclepore and Whatman have been compared. The filter media were extracted with dilute nitric acid and the element contents determined by ICP-MS. Large differences in blank values were observed between different filter materials. Glass fiber filters showed high blank values for a number of elements, whereas PTFE filters generally were the cleanest. However, most filter types showed high blank values of one or more elements of interest in aerosol measurements.