The accurate and rapid measurement of lead in airborne particulates is discussed with particular reference to so-called high-volume air samples. By standard addition analysis, it was found that there is no significant matrix error in measurements of lead taken on glass high-volume filters, within the range of concentrations investigated. This applies to varying or fixed amounts of the glass filter matrix. Recovery of standard added lead is quantitative. Although glass fibre sheet is much too impure for the analysis of most airborne metals, it is possible to analyze lead since the blank is reasonably uniform and since the amounts of lead on such a filter are large in comparison to the blank. Some additional corroboration has been obtained that the distribution of lead is uniform across the total exposed area of the filter. The final error of the lead measurement, as reported, is likely to be more largely a function of sampling problems such as time and flow measurements and particulate fall off and disturbance in sampling, transit and storage.
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