MONITORING AND LABORATORY DIVISION
STANDARD OPERATING PROCEDURE
S.O.P. No. MLD 061 - Standard Operating Procedure (SOP) for the Trace Elemental Analysis of Ambient Air Particulate Samples Using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)
This document details a gentle reflux technique to remove particulates from low-volume Teflon air sampling filters sized 37- and 47-millimeters in diameter.
SUMMARY OF METHOD
An exposed Teflon ambient air particulate filter is refluxed in a dilute-mixed-acid solution. The resulting extract is analyzed for elemental content using an ICP-MS. This method uses an ultrasonic nebulizer serially configured with a desolvator; a pneumatic nebulizer is an acceptable alternative.
Teflon filters appear to have inconsistent elemental contamination of analytes commonly reported for air samples collected on Teflon filters.
Although not specified herein, this reflux method is also suitable for segments of high-volume ambient air samples collected on quartz or glass micro-fiber filter segments, provided the extracts are vacuum-filtered of all debris greater than 0.45-microns before analysis by ICP-MS.