(相關資料圖)

食品安全關乎人類健康和社會福祉。稻米是世界上一半以上人口的主食，極易受重金屬污染。為了最大限度降低健康風險，國際組織和各國政府制定了稻米重金屬的最大可接受濃度（MAC）。然而，食用人群的個體差異也會對人體健康風險產生重要影響，致使長期暴露于低于MAC濃度的稻米仍可能對部分人群存在健康風險。

針對受體和區域飲食習慣差異對健康風險的影響尚不清晰這一問題，土壤化學與環境課題組聯合概率和模糊方法，精準識別了全國32個省份的關鍵受體，并測算了相應健康風險的超標概率，評估了不同省份5種重金屬(鎘、砷、汞、鉛、鉻)對健康風險的貢獻率。研究結果表明，長期食用符合食品安全國家標準的稻米仍會可能造成不可忽視的健康風險，而長期暴露的兒童和幼兒最為嚴重。這種健康風險主要來自砷與鎘。由于貿易發生空間轉移等因素的影響，土壤重金屬污染區與健康高風險區空間分布并不完全吻合。本研究近一步提高了重金屬污染人體健康風險評估的精準性，為食品安全標準優化與農業污染治理規劃提供理論支撐。

我校資源與環境學院碩士研究生魏仁皓為論文第一作者，陳暢副教授為通訊作者。資源與環境學院譚文峰教授、王真教授、劉朝陽副教授、湖北省生態環境科學研究院蔡俊雄教授等參與了研究工作。該研究得到了國家自然科學基金、湖北省自然科學基金和湖北省創新研究崗位項目的資助。

【英文摘要】

Long-term consumption of rice containing heavy metal(loid)s poses significant risks to public health, which can be scientifically evaluated through food safety assessment. However, spatial variability and uncertainty in exposure parameters are generally neglected in existing food safety assessment standards. This study focused on rice consumption in 32 provinces of China, and extracted 3,376 data points of five heavy metal(loid)s (cadmium, arsenic, mercury, lead, and chromium) and two nutrient elements (copper and zinc) from 408 articles. Probability and fuzzy methods were integrated to cope with the spatial variability or uncertainty and more accurately evaluate the risk. The results demonstrated that long-term consumption of rice that meets the national food safety standards still can cause non-negligible health risks, particularly for children and toddlers with chronical exposure. Arsenic and Cd were found to be the most critical elements, which contribute to 64.57% and 22.38% of the overall human health risk, respectively. Fuzzy assessment indicated that the score in northern China is approximately eight folds of that in southern China, indicating that northern rice has lower risks and better nutrition. Our results demonstrate that the food safety standards need to be tailored according to local conditions with more specific receptor parameters and risk acceptance.

論文鏈接：https://www.nature.com/articles/s43247-023-00723-7