Heavy metal pollution characteristics and exposure risk assessment of agricultural products in Xizang Autonomous Region

Xizang, with its sparse population but vast territory, serves as a strategic reserve for China’s mineral resources, boasting rich deposits of diverse metallic elements. However, ongoing mining activities in recent years have significantly raised concerns about heavy metal contamination in the region. Although numerous studies have addressed the occurrence of heavy metals in agricultural products from Xizang, there have not yet been a systematic synthesis of contamination patterns and associated health risks. In this review, we collected and analyzed concentration data for arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb) and mercury (Hg) in five major categories of Tibetan food products—cereals and their derivatives, vegetables and their derivatives, meats, aquatic products, as well as milk and dairy products. The dietary exposure risks were quantified based on regional consumption patterns. The result revealed distinct high‐plateau dietary exposure characteristics: animal‐derived foods were the principal sources of Cd and Hg exposure, whereas cereals predominantly contributed to As, Cr and Pb intake. The mean estimated daily intakes of As, Cd, Cr, Pb and Hg among Tibetan residents were 53.3, 29.1, 92.1, 84.6 and 18.8 μg·d−1, respectively, all below the corresponding FAO/WHO provisional tolerable daily intake limits. This review thus provides a comprehensive dataset for understanding heavy‐metal levels in Tibetan agricultural products and supports further risk management of dietary heavy‐metal exposure.