Department of Civil and Environmental Engineering, Water Research Group, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia.
Department of Civil and Environmental Engineering, Water Research Group, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia.
Sci Total Environ. 2018 Sep 1;635:35-44. doi: 10.1016/j.scitotenv.2018.04.065. Epub 2018 Apr 13.
Drinking water is a potential source of exposure to lead (Pb), which can pose risk to humans. The regulatory agencies often monitor Pb in water treatment plants (WTP) and/or water distribution systems (WDS). However, people are exposed to tap water inside the house while water may stay in the plumbing premise for several hours prior to reaching the tap. Depending on stagnation period and plumbing premise, concentrations of Pb in tap water can be significantly higher than the WDS leading to higher intake of Pb than the values from WDS or WTP. In this study, concentrations of Pb and water quality parameters were investigated in WDS, plumbing pipe (PP) and hot water tanks (HWT) for 7months. The samples were collected and analyzed on bi-weekly basis for 7 times a day. Several linear, non-linear and neural network models were developed for predicting Pb in PP and HWT. The models were validated using the additional data, which were not used for model development. The concentrations of Pb in PP and HWT were 1-1.17 and 1-1.21 times the Pb in WDS respectively. Concentrations of Pb were higher in summer than winter. The models showed moderate to excellent performance (R=0.85-0.99) in predicting Pb in PP and HWT. The correlation coefficients (r) with the validation data were in the ranges of 0.76-0.90 and 0.97-0.99 for PP and HWT respectively. The models can be used for predicting Pb in tap water, which can assist to better protect the humans.
饮用水是铅（Pb）暴露的潜在来源，这可能对人类构成风险。监管机构通常会监测水处理厂（WTP）和/或供水管网系统（WDS）中的 Pb。然而，人们在家中使用自来水时，水可能会在到达水龙头之前在管道系统中停留数小时。根据停滞时间和管道系统的不同，自来水龙头中的 Pb 浓度可能会明显高于 WDS，导致 Pb 的摄入量高于 WDS 或 WTP 的数值。在这项研究中，研究人员在 7 个月的时间里调查了 WDS、管道（PP）和热水箱（HWT）中的 Pb 浓度和水质参数。每天分 7 次，每两周收集并分析一次样本。针对 PP 和 HWT 中的 Pb 建立了几个线性、非线性和神经网络模型。使用未用于模型开发的额外数据验证了模型。PP 和 HWT 中的 Pb 浓度分别是 WDS 中 Pb 浓度的 1-1.17 倍和 1-1.21 倍。夏季的 Pb 浓度高于冬季。这些模型在预测 PP 和 HWT 中的 Pb 方面表现出中等至优秀的性能（R=0.85-0.99）。与验证数据的相关系数（r）分别在 0.76-0.90 和 0.97-0.99 之间。这些模型可用于预测自来水中的 Pb，这有助于更好地保护人类。
