Mielke H W, Dugas D, Mielke P W, Smith K S, Gonzales C R
Institute of Bioenvironmental Toxicology, Xavier University, New Orleans, LA 70125, USA.
Environ Health Perspect. 1997 Sep;105(9):950-4. doi: 10.1289/ehp.97105950.
This study evaluates associations between soil lead concentrations (SPb), age of housing, and blood lead levels (BPb) of children in metropolitan New Orleans and Lafourche Parish, Louisiana. The database includes over 2,600 SPb and 6,000 BPb samples paired by their median values and pre-1940 housing percentages for 172 census tracts. Associations were evaluated with Fisher's exact test and Spearman's rho test and modeled with the least sum of absolute deviations regression. Census tracts with low SPb are associated with new housing, but census tracts with high SPb are evenly split between old and new housing [Fisher's exact test, p = 8.60 X 10(-13) for the percentage of housing built before 1940 (percent pre-1940 housing) versus SPb]. The p-value for SPb versus BPb is 12 orders of magnitude stronger than the p-value for percent pre-1940 housing versus BPb. Census tracts with low BPb are associated with new housing, but census tracts with high BPb are split evenly between old and new housing (Fisher's exact test, p = 1. 67 X 10(-12) for percent pre-1940 housing versus BPb). Census tracts with high SPb are associated with high BPb and census tracts with low SPb are associated with low BPb (Fisher's exact test, p = 3.18 X 10(-24) for BPb versus SPb). The Spearman's rho test of the association of SPb and BPb in Orleans and Lafourche Parishes yielded a p-value of 6.12 X 10(-24). The least sum of absolute deviations regression model of the data is BPb = 1. 845 + 0.7215 (SPb)0.4. A comparison of the modeled BPb versus observed BPb has an r(2) of 0.552 and a p-value of 2.83 X 10(-23) that this relation was due to chance. If blood lead in children is more closely associated to soil lead than to the age of housing, then primary lead prevention should also include soil lead.
本研究评估了路易斯安那州新奥尔良市和拉福什教区儿童的土壤铅浓度（SPb）、房屋年代与血铅水平（BPb）之间的关联。该数据库包含172个人口普查区的2600多个SPb样本和6000多个BPb样本，这些样本按中位数以及1940年前房屋所占百分比进行配对。采用Fisher精确检验和Spearman秩相关检验评估关联，并使用绝对偏差总和最小回归进行建模。SPb值低的人口普查区与新建房屋相关，但SPb值高的人口普查区中，新旧房屋数量相当[对于1940年前建造的房屋所占百分比（1940年前房屋百分比）与SPb，Fisher精确检验，p = 8.60×10⁻¹³]。SPb与BPb的p值比1940年前房屋百分比与BPb的p值强12个数量级。BPb值低的人口普查区与新建房屋相关，但BPb值高的人口普查区中，新旧房屋数量相当（对于1940年前房屋百分比与BPb，Fisher精确检验，p = 1.67×10⁻¹²）。SPb值高的人口普查区与BPb值高相关，SPb值低的人口普查区与BPb值低相关（对于BPb与SPb，Fisher精确检验，p = 3.18×10⁻²⁴）。对奥尔良和拉福什教区SPb与BPb关联的Spearman秩相关检验得出p值为6.12×10⁻²⁴。数据的绝对偏差总和最小回归模型为BPb = 1.845 + 0.7215(SPb)⁰.⁴。将建模得到的BPb与观察到的BPb进行比较，r²为0.552，p值为2.83×10⁻²³，表明这种关系是偶然产生的概率。如果儿童血铅与土壤铅的关联比与房屋年代的关联更紧密，那么主要的铅预防措施也应包括土壤铅。
