B-HIVE: Beeswax hydrogen isotopes as validation of environment. Part I: Bulk honey and honeycomb stable isotope analysis

Stable isotope analysis is an established method for detecting honey adulteration. We extend its application to include honey and honeycomb region-of-origin assignment using hydrogen (δ²H) and oxygen (δ¹⁸O) isotopes. We observed that liquid honey δ²H and δ¹⁸O values had the potential to change because of water absorption and H atom exchange between sugars and water vapour. This suggested that liquid honey has limited use for geo-location, because specimens will record analysis location humidity. Paired liquid honey and honeycomb δ²H values were significantly correlated; therefore, we propose using wax δ²H values for region-of-origin assignment. We observed significant correlations between beeswax δ²H values and both mean annual precipitation and tap water δ²H values predicted for hive locations, suggesting that geographical variation in water δ²H values are recorded by beeswax δ²H values. This survey demonstrates the promise of stable isotopes for region-of-origin assignment, using honeycomb wax δ²H values, which complements carbon isotope analysis to detect adulteration.