Hochi Y, Kido T, Nogawa K, Kito H, Shaikh Z A
Department of Hygiene, Chiba University School of Medicine, Japan.
J Appl Toxicol. 1995 Mar-Apr;15(2):109-16. doi: 10.1002/jat.2550150209.
To determine the maximum allowable intake limits for chronic dietary exposure to cadmium (Cd), the dose-response relationship between total Cd intake and prevalence of renal dysfunction was examined using general linear models considering the effect of age as a confounder. The target population comprised 1850 Cd-exposed and 294 non-exposed inhabitants of Ishikawa, Japan. They were divided into 96 subgroups by sex, age (four categories) cadmium concentrations in rice (three categories) and length of residence (four categories). As indicators of the cadmium-induced renal dysfunction, glucose, total protein, amino nitrogen, beta 2-microglobulin and metallothionein in urine were employed. General linear models were fitted statistically to the relationship among prevalence of renal dysfunction, sex, age and total Cd intake. Prevalence of abnormal urinary findings other than glucosuria had significant associations with total Cd intake. When total Cd intake corresponding to the mean prevalence of each abnormal urinary finding in the non-exposed subjects was calculated using general linear models, total Cd intakes corresponding to glucosuria, proteinuria, aminoaciduria (men only) and proteinuria with glucosuria were determined to be ca. 2.2-3.8 g and those corresponding to prevalence of metallothioneinuria were calculated as ca. 1.5-2.6 g. The low-molecular-weight protein in urine was confirmed to be a more sensitive indicator of renal dysfunction, and these total Cd intake values were close to those calculated previously by simple regression analysis, suggesting them to be reasonable values as the maximum allowable intake of Cd.
为确定镉（Cd）慢性膳食暴露的最大允许摄入量限值，使用考虑年龄为混杂因素的一般线性模型，研究了总镉摄入量与肾功能障碍患病率之间的剂量反应关系。目标人群包括1850名日本石川县镉暴露居民和294名非暴露居民。他们按性别、年龄（4个类别）、大米中的镉浓度（3个类别）和居住时长（4个类别）分为96个亚组。作为镉诱导的肾功能障碍指标，采用了尿液中的葡萄糖、总蛋白、氨基氮、β2微球蛋白和金属硫蛋白。对肾功能障碍患病率、性别、年龄和总镉摄入量之间的关系进行了统计学上的一般线性模型拟合。除糖尿外的异常尿液检查结果患病率与总镉摄入量有显著关联。当使用一般线性模型计算非暴露受试者中每种异常尿液检查结果平均患病率对应的总镉摄入量时，确定糖尿、蛋白尿、氨基酸尿（仅男性）和糖尿伴蛋白尿对应的总镉摄入量约为2.2 - 3.8克，金属硫蛋白尿患病率对应的总镉摄入量计算为约1.5 - 2.6克。尿液中的低分子量蛋白被确认为肾功能障碍更敏感的指标，这些总镉摄入量值与先前通过简单回归分析计算的值接近，表明它们作为镉的最大允许摄入量是合理值。
