Department of Public Health, Food Studies, and Nutrition, Syracuse University, Syracuse, NY 13204, USA.
Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York State Department of Health, Albany, NY 12201, USA; Department of Environmental Health Sciences, School of Public Health, University at Albany, Rennselaer, NY 12144, USA.
Environ Res. 2019 Mar;170:463-471. doi: 10.1016/j.envres.2018.12.069. Epub 2019 Jan 6.
Heightened blood lead levels (BLL) are associated with cognitive deficiencies and adverse behavioral outcomes. Lead-contaminated house dust is the primary source of exposure in U.S. children, and evidence suggests that even background (low-level) exposure has negative consequences. Identifying sources of background exposure is of great public health significance because of the larger number of children that can be affected.
Blood lead was assessed in a bi-racial sample of children from Syracuse, NY, aged 9-11, using established biomonitoring methods. The spatial density of vacant properties was modelled from publicly available georeferenced datasets. Further, regression models were used to measure the impact of this spatial density variable on children's BLL.
In a sample of 221 children, with a mean BLL of 1.06 µg/dL (SD = 0.68), results showed increases in spatial density of vacant properties predict increases in median blood-PB levels, b = 0.14 (0.06-0.21), p < .001. This association held true even after accounting for demographic covariates, and age of individual housing. Further analysis showed spatial autocorrelation of the residuals changed from a clustered pattern to a random pattern once the spatial density variable was introduced to the model.
This study is the first to identify a background-lead exposure source using spatial density modelling. As vacant properties deteriorate, lead-contaminated dust likely disperses into the surrounding environment. High-density areas have an accumulation of lead hazards in environmental media, namely soil and dust, putting more children at risk of exposure.
血液铅水平（BLL）升高与认知缺陷和不良行为结果有关。受铅污染的房屋灰尘是美国家庭儿童暴露的主要来源，有证据表明，即使是背景（低水平）暴露也会产生负面影响。由于受影响的儿童人数较多，确定背景暴露的来源具有重要的公共卫生意义。
使用既定的生物监测方法，对来自纽约州锡拉丘兹的 9-11 岁的双种族儿童进行了血液铅检测。利用公开的地理参考数据集对空置物业的空间密度进行建模。此外，还使用回归模型来衡量该空间密度变量对儿童 BLL 的影响。
在 221 名儿童的样本中，平均 BLL 为 1.06µg/dL（SD=0.68），结果显示，空置物业空间密度的增加预测了血液 PB 水平中位数的增加，b=0.14（0.06-0.21），p<0.001。即使考虑了人口统计学协变量和个人住房的年龄，这种关联仍然成立。进一步的分析表明，一旦将空间密度变量引入模型，残差的空间自相关从聚类模式变为随机模式。
这项研究首次使用空间密度建模来确定背景铅暴露源。随着空置物业的恶化，受铅污染的灰尘可能会扩散到周围环境中。高密度区域的环境介质（即土壤和灰尘）中存在大量的铅危害，使更多的儿童面临暴露的风险。
