Research Projects

Results for analysis of a subset of 71 Lake Tahoe Atmospheric Deposition Study (LTADS) ambient sample filters via synchrotron sourced x-ray fluorescence (s-XRF) are presented. A rigorous statistical analysis of phosphorous concentration data reveals a lower quantifiable limit of 15 nanograms per cubic meter for the s-XRF analysis results and 30 ng/m3 for DRI analyses for the LTADS ambient filters. Comparison of results for major elements between the s-XRF and DRI technique indicates no significant bias between analytical protocols for ambient samples. Additionally, 21 source samples (7 smoke and 14 roadway) were analyzed via s-XRF. In contrast to the ambient samples, differences were observed when comparing datasets. A nonuniform deposit on the source samples, however, is suggested as being responsible for the observed differences in quantitative results when comparing the s-XRF and DRI data.RACT