Determination of phosphorus and other elements in atmospheric aerosols using synchrotron total‐reflection X‐ray fluorescence

Abstract

In this study, P and other low Z elements were determined in aerosol particulates from ambient air using synchrotron radiation‐induced total‐reflection X‐ray fluorescence analysis. Atmospheric transport of nutrients such as P or Si to the oceans is a key factor to marine plankton growth. Concentration of these elements in marine air masses is generally low (P < 10 ng/m3). Therefore, analytical procedures enabling for low detection limits are of interest. Because particle size is strongly correlated to its origin and sedimentation, the aerosols were collected with the aid of a low‐pressure Berner impactor, which separates the aerosol particulates in nine size fractions with the smallest fraction from 15 to 30 nm. To be able to determine low Z elements, measurements were performed under vacuum conditions at the FLUO beamline at the ANKA synchrotron. An excitation energy of 3.5 keV near the P K‐edge but below the Ca K absorption edge was chosen to avoid interferences of the P K‐line with the detector escape artifact of the Ca‐Kα line. The result showed P was present in concentration from 2 to 180 ng/m3. Detection limits were found to be generally 0.2–0.3 ng/m3 for a collecting time of 1 h for the aerosols, which is an improvement to detection limits reported in other studies. Other elements such as S, Cl, and Si were determined as well. Si like P is a nutrient for marine plankton (diatoms). S and Cl play an important role in cloud formation, e.g. polar stratospheric clouds. Copyright © 2013 John Wiley & Sons, Ltd.

Innovative methods in soil phosphorus research: A review

“…Synchotron based total X-ray fluorescence (TXRF) spectroscopy is one of the many varieties of XRF, capable of determining elemental concentrations in the ultra-trace range; indeed, measurements of P t atmospheric aerosol particulates are possible at concentrations as low as 0.2 to 0.3 ng P m −3 ( Fittschen et al, 2013 ). This is achieved by decreasing the incidence angle of the incoming beam below the critical angle of total reflection; this minimizes penetration depth, absorption and scattering of the incoming beam in the sample matrix and, thus, reduces background noise and increases sensitivity ( Wobrauschek , 2007 ).…”

Recent advances in analysis of trace elements in environmental samples by X-ray based techniques (IUPAC Technical Report)

“…Similar spectroscopy measurements were performed on the iron K-edge [166] to investigate the role of Fe in aerosols as oceanic micro nutrient, stimulating the growth of phytoplankton in the world seas. Light elements are the focus of studies of nitrogen and sulfur compounds in coastal Antarctic fine aerosol particles [167] and phosphorous determination in atmospheric aerosols [168]. Very recently, Shaltout et al [169] studied size-fractionated aerosols collected from Jeddah, Saudi Arabia.…”

2014 atomic spectrometry update – a review of advances in environmental analysis

“…Divergences noted for Mn, Ni and Pb at lower concentrations were attributed to spectral overlaps that compromised FP calculations and to the presence of Ni in blank lters. Trace levels of P were determined 74 in marine aerosols by SRXRF to study the atmospheric transfer of nutrients to the oceans and their role in marine plankton growth. Phosphorous was present in the range 2-180 ng m À3 and the method LOD was ca.…”