A guide for proper utilisation of stable isotope reference materials.

Area of Science:

• Geochemistry
• Analytical Chemistry
• Environmental Science

Background:

• Scientific publications on stable isotope ratios often exhibit flawed calibration and normalization practices.
• Non-adherence to the identical treatment principle for samples and standards, and inconsistent nomenclature, compromise data reliability.
• Ambiguity and jargon hinder interdisciplinary communication in isotope science.

Purpose of the Study:

• To expose common misconceptions and errors in stable isotope analysis.
• To provide guidance for reproducible generation, normalization, and reporting of isotope data.
• To offer a resource for selecting appropriate reference materials based on sample matrices.

Main Methods:

• Review of common analytical practices and reporting standards in stable isotope research.
• Identification of deviations from SI-mandated and IUPAC-recommended guidelines.
• Compilation of information on light stable isotope reference materials and their matrix compatibility.

Main Results:

• Identified widespread issues in calibration, normalization, and data reporting of stable isotope ratios.
• Highlighted violations of the identical treatment principle and inconsistent use of nomenclature.
• Provided a framework for improving the reproducibility and accuracy of isotope data.

Conclusions:

• Adherence to standardized practices is crucial for the exactness and reproducibility of stable isotope data.
• Clear nomenclature and proper normalization are essential for reliable interdisciplinary communication.
• Selecting chemically similar reference materials enhances the accuracy of isotope measurements.