van Wijnen J H, Clausing P, Brunekreef B
Section of Public Health and Environment, Municipal Health Service Amsterdam, The Netherlands.
Environ Res. 1990 Apr;51(2):147-62. doi: 10.1016/s0013-9351(05)80085-4.
The amount of soil ingested by young children was estimated by measuring the titanium, aluminum, and acid-insoluble residue in soil and feces. As intake of each of these tracers is also possible from sources other than soil ingestion, the amount of soil ingested was estimated to be not higher than the lowest of the three separate estimates. This estimate, the limiting tracer method (LTM) value, was then corrected for the similarly calculated mean LTM value for a group of hospitalized children without access to soil and dust. The study groups included children in three different environmental situations: day-care centers, campgrounds, and hospitals. The day-care center groups were sampled twice. From these groups, 162 children produced usable feces samples during both sampling periods. The camping groups and the hospitalized (control) group were sampled once. For the day-care center groups, the estimated geometric mean soil intake varied from 0 to 90 mg/day and for the camping groups these estimates ranged from 30 to 200 mg/day (in dry weight). Using estimates of the "true" between-child GSD values, the 90th percentile of the estimated soil intakes was shown to be typically 40-100 mg/day higher than the geometric means of these estimates. In the day-care center groups few correlations with the geometric mean LTM values were found for variables concerning living conditions, mouthing behavior, playing habits, etc. A strong correlation was found with weather. During dry weather the younger children especially showed higher LTM values. In the camping group the weather also influenced the mean LTM value only in the younger age groups. Analysis of variance showed that a single LTM value of a child has a low predictive value with regard to the LTM value of the next few days or that of a few months later. Therefore it seems reasonable to use group statistics as estimates of soil ingestion in health risk assessments of soil pollution incidents.
通过测量土壤和粪便中的钛、铝以及酸不溶残渣来估算幼儿摄入的土壤量。由于这些示踪剂中的每一种也可能从土壤摄入以外的来源获取，因此估计摄入的土壤量不高于三个单独估算值中的最低值。然后，针对一组无法接触土壤和灰尘的住院儿童，对该估算值（即极限示踪剂法 (LTM) 值）进行了类似计算的平均 LTM 值校正。研究组包括处于三种不同环境状况下的儿童：日托中心、露营地和医院。日托中心组进行了两次采样。在这两个采样期间，这些组中有162名儿童提供了可用的粪便样本。露营组和住院（对照）组进行了一次采样。对于日托中心组，估计的几何平均土壤摄入量在0至90毫克/天之间，而露营组的这些估计值在30至200毫克/天之间（干重）。利用“真实的”儿童间几何标准差 (GSD) 值的估计，估计土壤摄入量的第90百分位数通常比这些估计值的几何平均值高40 - 100毫克/天。在日托中心组中，未发现与生活条件、口含行为、玩耍习惯等变量与几何平均LTM值有显著相关性。但发现与天气有很强的相关性。在干燥天气下，尤其是年幼儿童的LTM值更高。在露营组中，天气也仅对较年幼年龄组的平均LTM值有影响。方差分析表明，儿童的单个LTM值对未来几天或几个月后的LTM值预测价值较低。因此，在土壤污染事件的健康风险评估中，使用群体统计数据作为土壤摄入量的估计似乎是合理的。
