Reliable Ultra Trace Analysis of Cd, U and Zn Concentrations in Greenland Snow and Ice by Using Ultraclean Methods for Contamination Control

• Published in: Molecules
• Main Authors: Changhee Han, Heejin Hwang, Jung-Ho Kang, Sang-Bum Hong, Yeongcheol Han, Khanghyun Lee, Soon Do Hur, Sungmin Hong
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2020
• Subjects: ultraclean procedure; ultralow trace elements; contamination; Greenland snow and ice; seasonal variations; anthropogenic inputs; Organic chemistry; QD241-441; Greenland; Ice Sheet
• Online Access: https://doi.org/10.3390/molecules25112519; https://doaj.org/article/8fb3ff6e382f4c968df5782228b4a93e

This study presents ultraclean procedures used in the challenging task of determining trace elements at or below the pg/g concentration level encountered in Greenland snow and ice. In order to validate these ultraclean procedures, recent snowfall and Holocene ice from northwest Greenland were analyzed for Cd, U, and Zn concentrations. The total procedural blanks brought through the entire measurement procedure proved to be negligible, compared to trace element concentrations, measured in snow and ice samples. This validates the overall practicality of the proposed ultraclean procedures, thereby ensuring the reliable measurements of ultra-trace analysis. A comparison between our study and published data shows that improper procedures employed throughout all stages, from field sampling to analysis to elevate the concentrations by several orders of magnitude, relative to the reliable concentration ranges. The risk of contamination exposure for selected trace elements appears to increase in the order of U < As ≤ Pb < Cd < Zn. Reliable measurements of Cd, U, and Zn concentrations in snow and ice allowed us to interpret the data in terms of seasonal variations in the inputs of crustal and anthropogenic sources to Greenland ice sheet.