Jones Rachael M, Graber Judith M, Anderson Robert, Rockne Karl, Turyk Mary, Stayner Leslie T
Divisions of Environmental and Occupational Health Sciences (Dr Jones) and Epidemiology and Biostatistics (Drs Graber, Turyk, and Stayner), School of Public Health, and Department of Civil and Materials Engineering, College of Engineering (Dr Rockne), University of Illinois at Chicago.
J Public Health Manag Pract. 2014 Mar-Apr;20(2):210-9. doi: 10.1097/PHH.0b013e3182980ca2.
Environmental Public Health Tracking (EPHT) tracks the occurrence and magnitude of environmental hazards and associated adverse health effects over time. The EPHT program has formally expanded its scope to include finished drinking water quality.
Our objective was to describe the features, strengths, and limitations of using finished drinking water quality data from community water systems (CWSs) for EPHT applications, focusing on atrazine and nitrogen compounds in 8 Midwestern states.
Water quality data were acquired after meeting with state partners and reviewed and merged for analysis.
Data and the coding of variables, particularly with respect to censored results (nondetects), were not standardized between states. Monitoring frequency varied between CWSs and between atrazine and nitrates, but this was in line with regulatory requirements. Cumulative distributions of all contaminants were not the same in all states (Peto-Prentice test P < .001). Atrazine results were highly censored in all states (76.0%-99.3%); higher concentrations were associated with increased measurement frequency and surface water as the CWS source water type. Nitrate results showed substantial state-to-state variability in censoring (20.5%-100%) and in associations between concentrations and the CWS source water type.
Statistical analyses of these data are challenging due to high rates of censoring and uncertainty about the appropriateness of parametric assumptions for time-series data. Although monitoring frequency was consistent with regulations, the magnitude of time gaps coupled with uncertainty about CWS service areas may limit linkage with health outcome data.
环境公共卫生追踪（EPHT）会随时间追踪环境危害的发生情况及严重程度，以及相关的不良健康影响。EPHT项目已正式扩大其范围，将成品饮用水质量纳入其中。
我们的目的是描述将社区供水系统（CWS）的成品饮用水质量数据用于EPHT应用的特点、优势和局限性，重点关注美国中西部8个州的阿特拉津和氮化合物。
在与州合作伙伴会面后获取水质数据，并进行审查和合并以进行分析。
各州之间的数据和变量编码，尤其是关于截尾结果（未检出）的编码并不统一。CWS之间以及阿特拉津和硝酸盐之间的监测频率各不相同，但这符合监管要求。所有污染物的累积分布在各州并不相同（Peto - Prentice检验P <.001）。在所有州，阿特拉津的结果截尾率都很高（76.0% - 99.3%）；较高浓度与测量频率增加以及CWS源水类型为地表水有关。硝酸盐结果在截尾情况（20.5% - 100%）以及浓度与CWS源水类型之间的关联方面，各州之间存在很大差异。
由于截尾率高以及时间序列数据参数假设的适用性存在不确定性，对这些数据进行统计分析具有挑战性。尽管监测频率符合规定，但时间间隔的大小以及CWS服务区域的不确定性可能会限制与健康结果数据的关联。
