Abstract
CSIA based on GC-IRMS has been widely used in many fields in USA and Europe. The major applications of CSIA is source identification of same material, such as, identifying pollution source in environmental forensics, monitoring biodegradation of contaminants in ground water at polluted site and evaluating natural attenuation, identifying explosives, ignitable liquid and tracing origin of illicit drugs in forensic science, proof of authenticity of various foods, beverage products, drug products or quality control for food and drug applications. Especially, CSIA was officially accepted by IOC (International Olympic Committee) for differentiating between endogenous human testosterone and exogenous testosterone in order to identify cases of testosterone doping in sporting events in 1997. The purpose of this thesis is using GC-IRMS to develop CSIA technology for source identification of organic solvents in industrial wastes (chapter 2), monitoring biodegradation of contaminants in ground water at polluted site for evaluating extent of biodegradation in ground water and evaluating feasibility of bioremediation (chapter 3), source identification of 16 PAHs (Polyaromatic hydrocarbons) in sediments from Kaohsiung Harbor, Taiwan (chapter 4) and tracing origins of urinary methamphetamines from suspected drug abusers (chapter 5). The applications of CSIA with GC-IRMS are limited, presumably due to its poor sensitivity, serious matrix interference and isotope ratio data uncertainty. So, in addition to develop GC-IRMS analysis method, we had to develop GC-IRMS calibration method to obtain precise and accurate □13C, □15N, develop SPME preconcentration technique to improve sensitivity, and develop pretreatment method to remove matrix interferences for successful analysis of environmental or urinary real samples. For data processing, we combined one way ANOVA, factor analysis, and cluster analysis to differentiate relationships between same materials from different source in order to results correctly. We have found that □□□C of some characteristic components in industrial wastes, such as capolactam, methyl isobutyl ketone, acetone…etc. could be used as an indicator for source identification. The extends of biodegradation (B) of contaminants could be estimated by enrichment tendency of □□□C of contaminants. The biodegradation efficiency of chlorine containing solvents in ground water at polluted site were 40 %, 90 %, respectively, indicating that biodegradation occurred at the polluted site. PAHs in sediments from Kaohsiung Harbor are mainly pyrogenic, else are petrogenic and biogenic. Most come from coal pyrolysis, smelter emission, vehicular emission and incinerator emission; else come from fuel of fish boat, cruise ship leaking, photosynthesis of plants, and biodegradation. □□□C and □□□N of methamphetamine in 11 urinary sample from suspected drug abusers were divided into two groups, presumably due to difference in seizing area. Two ephedrine standards were found to from semi synthesis and synthesis based on their □□□C and □□□N values. Two methamphetamine standards were formed to be synthesis routes from ephedrine; where as one was synthesized from synthetic precursors. The results evidence that CSIA based on GC-IRMS could be successfully applied to source identification of environmental pollutants, tracing origins of illicit drugs, and monitoring biodegradation of contaminants in ground water at polluted site.