The drinking water contamination crisis in Flint: Modeling temporal trends of lead level since returning to Detroit water system.
The drinking water contamination crisis in Flint: Modeling temporal trends of lead level since returning to Detroit water system.
复制标题
弗林特的饮用水污染危机：对返回底特律供水系统后铅含量的时间趋势进行建模。
DOI：
10.1016/j.scitotenv.2016.09.207
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Goovaerts,Pierre
中科院分区：
文献类型：
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作者：
Goovaerts,Pierre
自弗林特恢复危机前的饮用水来源以来，已经收集了近2.5万个水样，并在1万个住宅中进行了铅和铜的测试。本文首先介绍了铅数据的分析和时间趋势建模，为这种干预的影响提供了新的见解。分析开始于对底特律恢复供水后11个月内测量的所有水铅水平(WLL)进行地理编码。每个数据都被分配到相应的纳税地块单位，并链接到二级数据集，如服务线的组成、建成年份或人口普查区域的贫困水平。分析中只使用了在城市范围内收集的住宅地块的数据。弗林特数据的一个主要特点是通过两种不同的抽样举措进行收集：(1)自愿或房主驱动的抽样，即有关公民决定购买检测试剂盒并在自己的(非哨点)进行抽样；(2)国家控制的抽样，即在技术小组(哨点)对居民进行培训后，每两周在选定的地点收集数据。从这两个数据集建模的时间趋势被发现在统计学上不同，超过WLL阈值的哨点数据更少，范围从10到50μg/L。即使在调整住房特征后，在非哨点站点测量WLL超过15μg/L的优势比(OR)显著为1(OR=1.480)，并且随着阈值的增加(50μg/L的OR=2.055)。Joinpoint回归显示，自底特律水系恢复以来，全市范围内超过15μg/L的数据百分比呈现出四个连续的趋势。尽管最近水质有所改善，但需要找出采样计划之间存在差异的罪魁祸首，因为这会影响暴露评估，并可能影响是否遵守铅和铜规则。
Since Flint returned to its pre-crisis source of drinking water close to 25,000 water samples have been collected and tested for lead and copper in > 10,000 residences. This paper presents the first analysis and time trend modeling of lead data, providing new insights about the impact of this intervention. The analysis started with geocoding all water lead levels (WLL) measured during an 11-month period following the return to the Detroit water supply. Each data was allocated to the corresponding tax parcel unit and linked to secondary datasets, such as the composition of service lines, year built, or census tract poverty level. Only data collected on residential parcels within the City limits were used in the analysis. One key feature of Flint data is their collection through two different sampling initiatives: (i) voluntary or homeowner-driven sampling whereby concerned citizens decided to acquire a testing kit and conduct sampling on their own (non-sentinel sites), and (ii) State-controlled sampling where data were collected bi-weekly at selected sites after training of residents by technical teams (sentinel sites). Temporal trends modeled from these two datasets were found to be statistically different with fewer sentinel data exceeding WLL thresholds ranging from 10 to 50 μg/L. Even after adjusting for housing characteristics the odds ratio (OR) of measuring WLL above 15 μg/L at non-sentinel sites is significantly > 1 (OR = 1.480) and it increases with the threshold (OR = 2.055 for 50 μg/L). Joinpoint regression showed that the city-wide percentage of WLL data above 15 μg/L displayed four successive trends since the return to Detroit Water System. Despite the recent improvement in water quality, the culprit for differences between sampling programs needs to be identified as it impacts exposure assessment and might influence whether there is compliance or not with the Lead and Copper Rule.