title: Rapid measurement of perchlorate in polar ice cores down to sub-ng L(-1) levels without pre-concentration.
abstract: An ion chromatography-electrospray ionization-tandem mass spectrometry (IC-ESI-MS/MS) method has been developed for rapid and accurate measurement of perchlorate in polar snow and ice core samples in which perchlorate concentrations are expected to be as low as 0.1 ng L(-1). Separation of perchlorate from major inorganic species in snow is achieved with an ion chromatography system interfaced to an AB SCIEX triple quadrupole mass spectrometer operating in multiple reaction monitoring mode. Under optimized conditions, the limit of detection and lower limit of quantification without pre-concentration have been determined to be 0.1 and 0.3 ng L(-1), respectively, with a linear dynamic range of 0.3-10.0 ng L(-1) in routine measurement. These represent improvements over previously reported methods using similar analytical techniques. The improved method allows fast, accurate, and reproducible perchlorate quantification down to the sub-ng L(-1) level and will facilitate perchlorate measurement in the study of natural perchlorate production with polar ice cores in which perchlorate concentrations are anticipated to vary in the low and sub-ng L(-1) range. Initial measurements of perchlorate in ice core samples from central Greenland show that typical perchlorate concentrations in snow dated prior to the Industrial Revolution are about 0.8 ng L(-1), while perchlorate concentrations are significantly higher in recent (post-1980) snow, suggesting that anthropogenic sources are a significant contributor to perchlorate in the current environment.
authors: South Dakota State University, Box 2202 Avera Health and Science Center, Brookings, SD, 57007, USA. kari.peterson@sdstate.edu.
authors: Kari
authors: K
authors: Peterson
authors: South Dakota State University, Box 2202 Avera Health and Science Center, Brookings, SD, 57007, USA.
authors: Jihong
authors: J
authors: Cole-Dai
authors: South Dakota State University, Box 2202 Avera Health and Science Center, Brookings, SD, 57007, USA.
authors: Derek
authors: D
authors: Brandis
authors: South Dakota State University, Box 2202 Avera Health and Science Center, Brookings, SD, 57007, USA.
authors: Thomas
authors: T
authors: Cox
authors: South Dakota State University, Box 2202 Avera Health and Science Center, Brookings, SD, 57007, USA.
authors: Scott
authors: S
authors: Splett
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000191:economics / Q000379:methods; D004784:Environmental Monitoring / Q000191:economics / Q000379:methods*; D007053:Ice / Q000032:analysis*; D057230:Limit of Detection; D010472:Perchlorates / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000191:economics / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000191:economics / Q000379:methods; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D007053:Ice; D010472:Perchlorates; D014874:Water Pollutants, Chemical; C494474:perchlorate
keywords: Ice core; Ion chromatography-tandem mass spectrometry; Perchlorate; Pollution; Ultra-trace analysis