Satarug Soisungwan, Vesey David A, Gobe Glenda C
Centre for Kidney Disease Research, Translational Research Institute, University of Queensland School of Medicine, Woolloongabba, Brisbane, Queensland, Australia.
Environ Health Perspect. 2017 Mar;125(3):284-288. doi: 10.1289/EHP108. Epub 2017 Mar 1.
Cadmium (Cd), a food-chain contaminant, is a significant health hazard. The kidney is one of the primary sites of injury after chronic Cd exposure. Kidney-based risk assessment establishes the urinary Cd threshold at 5.24 μg/g creatinine, and tolerable dietary intake of Cd at 62 μg/day per 70-kg person. However, cohort studies show that dietary Cd intake below a threshold limit and that tolerable levels may increase the risk of death from cancer, cardiovascular disease, and Alzheimer's disease.
We evaluated if the current tolerable dietary Cd intake guideline and urinary Cd threshold limit provide sufficient health protection.
Staple foods constitute 40-60% of total dietary Cd intake by average consumers. Diets high in shellfish, crustaceans, mollusks, spinach, and offal add to dietary Cd sources. Modeling studies predict the current tolerable dietary intake corresponding to urinary Cd of 0.70-1.85 μg/g creatinine in men and 0.95-3.07 μg/g creatinine in women. Urinary Cd levels of < 1 μg/g creatinine were associated with progressive kidney dysfunction and peripheral vascular disease. A urinary Cd of 0.37 μg/g creatinine was associated with breast cancer, whereas dietary Cd of 16-31.5 μg/day was associated with 25-94% increase in risk of estrogen receptor-positive breast cancer.
Modeling shows that dietary intake levels for Cd exceed the levels associated with kidney damage and many other adverse outcomes. Thus, the threshold level of urinary Cd should be re-evaluated. A more restrictive dietary intake guideline would afford enhanced health protection from this pervasive toxic metal. Citation: Satarug S, Vesey DA, Gobe GC. 2017. Health risk assessment of dietary cadmium intake: do current guidelines indicate how much is safe? Environ Health Perspect 125:284-288; http://dx.doi.org/10.1289/EHP108.
镉（Cd）作为一种食物链污染物，对健康危害极大。肾脏是慢性镉暴露后主要的受损器官之一。基于肾脏的风险评估确定尿镉阈值为5.24μg/g肌酐，70公斤体重的人镉的可耐受膳食摄入量为62μg/天。然而，队列研究表明，低于阈值限制的膳食镉摄入量以及可耐受水平可能会增加患癌症、心血管疾病和阿尔茨海默病死亡的风险。
我们评估了当前镉的可耐受膳食摄入量指南和尿镉阈值限制是否能提供充分的健康保护。
主食占普通消费者膳食镉总摄入量的40%-60%。贝类、甲壳类、软体动物、菠菜和内脏含量高的饮食会增加膳食镉来源。模型研究预测，当前可耐受膳食摄入量对应的男性尿镉为0.70-1.85μg/g肌酐，女性为0.95-3.07μg/g肌酐。尿镉水平<1μg/g肌酐与进行性肾功能不全和外周血管疾病有关。尿镉0.37μg/g肌酐与乳腺癌有关，而膳食镉16-31.5μg/天与雌激素受体阳性乳腺癌风险增加25%-94%有关。
模型显示，镉的膳食摄入量超过了与肾脏损害和许多其他不良后果相关的水平。因此，应重新评估尿镉阈值水平。更严格的膳食摄入量指南将为防范这种普遍存在的有毒金属提供更强的健康保护。引用文献：Satarug S, Vesey DA, Gobe GC. 2017.膳食镉摄入量的健康风险评估：当前指南是否表明多少摄入量是安全的？《环境健康展望》125:284-288；http://dx.doi.org/10.1289/EHP108 。
