“…[104] However,owing to the KIE, subtle variations in the isotopic composition, also known as isotopic fractionation, [105] can result in the accumulation of heavier isotopes in the residual substrate fraction of biological, chemical, or physical degradation processes.A s ar esult, the relative abundance measured in different materials can provide important environmental information on their origin and history. [106] Accordingly,a nalysis of naturally abundant stable isotope ratios,f or example,b y IRMS (isotope ratio MS), [107] IRIR (isotope ratio IR), [108] or ICP-MS (inductively coupled plasma MS), [109] has been recognized as ap owerful tool in forensic science,g eochemistry,p aleoclimatology,e cology,a nd physiology. [110] Applications are numerous and include,f or example,the origin and/ or counterfeit tracing of food, [111] water, [112] pollutants, [113] or pharmaceuticals, [114] and the isotopic characterization of drugs [115] and explosives, [116] as well as the fate assessment of contaminants in soils and aquifers.…”