Hygienic Assessment of Alimentary Exposure to Stable Strontium in Russia: A Risk Analysis

Introduction. Stable strontium (Sr) is a toxic trace element and a chemical analog of calcium. Its primary target is bone tissue, where it accumulates, disrupting mineralization and causing “strontium rickets”. Classified as a non-carcinogen with an oral reference dose (RfD) of 0.6 mg/kg bw/day. High variability of Sr levels in water and food across Russian regions necessitates a detailed risk assessment. This study evaluates alimentary Sr exposure by analyzing its content in drinking water and food products.

Methods. The analysis is based on a review of peer-reviewed literature and official Russian monitoring data on stable Sr concentrations in water. Non-carcinogenic risk was assessed using the Hazard Quotient (HQ) by comparing estimated daily intake with the RfD

Results. Sr content in Russian artesian water varies greatly, reaching 15.45 mg/L in the Smolensk region. The highest food levels were found in spices Trachyspermum ammi seeds (490 mg/kg) and fennel (183 mg/kg). According to published data, high concentrations are also known in nuts (almonds 15.7 mg/kg), dairy (hard cheese 12.0 mg/kg), mollusks (14.3 mg/kg), and fish liver (3.54 mg/kg). Legumes (3.34 mg/kg), chocolate (3.17 mg/kg), and spinach/cabbage (up to 2.65 mg/kg) also show significant levels. At average concentrations, total daily Sr intake yields an HQ within an acceptable range (<1.0). However, for some regions of Russia, high Sr in water together with consumption of products at maximum concentrations approaches threshold levels.

Conclusion. Alimentary exposure to Sr in Russia generally poses an acceptable non-carcinogenic risk for the average consumer. However, in certain biogeochemical provinces and among consumers on diets rich in Sr-accumulating foods, exposure may approach RfD. Such a scenario is also possible in other countries with similar hydrogeochemical conditions and dietary patterns. These findings highlight the need for regional monitoring and targeted risk management.

Funding. Ministry of Science and Higher Education of Russian Federation (FGMF-2025-0004).