Application of Compound-Specific Isotope Analysis (CSIA) in environmental surveys to distinguish different sources of contamination

Abstract

Compound-Specific Isotope Analysis (CSIA) is an analytical method that measures the ratios of stable isotopes and has been widely applied as an environmental forensic tool including, but not limited to, illicit drugs, explosives, drug control, and more recently contaminated groundwater studies. The current paper provides a brief description of how useful this technique can be as a powerful tool to distinguish different groundwater plumes (mainly chlorinated hydrocarbons) in an environmental forensic study. Based on a literature review, the basic principles of the technique, the isotope fractionation for chlorinated hydrocarbons in the environment, the equipment and real applications of the technique are all shown here. The combination of this technique with traditional methods, especially when isotopes of more than one element are analyzed, significantly increases the success of determining the origin of contaminants and identifying responsible parties in judicial disputes.