Application of isotope ratio mass spectrometry (IRMS) in the geographical determination of selected herbs: A review

Herbs have been consumed for their health benefits for centuries and are still attracting increasingly more attention. Their quality is prone to changes in climatic and geo−chemical conditions. Local cultivation patterns also impact the quality of herbs. Therefore, geographical origin is often regarded as an indicator of quality. However, profit−motivated fraud and adulterations degraded the quality of relevant products, and also destroyed the consumers’ health and trust. Isotope ratio mass spectrometry (IRMS) is particularly useful in verifying the origin of herbs as the isotopic composition of several light elements (C, H, O, N and S) contain information about the geographical locations. Changes in the isotopic composition cannot be identified by other techniques but may be detected using IRMS. In this review, current applications of IRMS in tracing ginseng, saffron, chrysanthemum flos and goji berries were discussed and future development was envisaged. • Determining the geographical origin of herbs is essential to protect consumers' health and fight against food frauds. • IRMS combined with other analytical techniques and statistical analyses has shown to be very useful for this purpose. • Isotope ratios of light elements (C, H, O, N and S) can help identify geographical origins of herbs. • Bulk stable isotope analysis has been intensively applied for such determination. • Compound specific isotope analysis has bright prospects of tracing the origins of herbs.