Lead (Pb) deposition onto new and biofilm-laden potable water pipes
Lead (Pb) deposition onto new and biofilm-laden potable water pipes
复制标题
铅 (Pb) 沉积在新的、充满生物膜的饮用水管上
DOI：
10.1016/j.chemosphere.2023.140135
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发表时间：
2023
期刊：
影响因子：
8.8
通讯作者：
Salehi, Maryam
中科院分区：
文献类型：
--
作者：
Hadiuzzaman, Md;Mirza, Nahreen;Brown, Shawn P.;Ladner, David A.;Salehi, Maryam
重金属与管道材料的相互作用是复杂的，因为管道内生物膜的形成不同，这些生物膜可以调节、转化和/或隔离重金属。本研究旨在阐明生物膜的存在对铅（Pb）在交联聚乙烯（PEX-A）、高密度聚乙烯（HDPE）和铜饮用水管道上积累的机制作用。为此，生物膜在新管道上生长了三个月。进行了为期5天的铅暴露实验，研究了铅在新管道和生物膜管道上的积累动力学。此外，还考察了铅初始浓度对铅在管道上积累速率的影响。结果表明，与铜管和HDPE管相比，PEX-A管上的生物膜生物量更大。经生物膜处理的塑料管的zeta负电位明显高于未处理的塑料管。在停滞条件下Pb暴露5天后，生物膜负载的PEX-A （980 μ m−2）和HDPE （1170 μ m−2）管道累积的Pb表面负荷分别是新PEX-A （265 μ m−2）和HDPE （329 μ m−2）管道的3倍以上。但在流动条件下，生物膜塑料管道上的铅积累量低于新管道。此外，随着初始Pb浓度的增加，生物膜管道的表面Pb积累速率高于停滞条件下的新管道。一级动力学模型最好地描述了在停滞和流动条件下新水管和有生物膜的水管上的铅积累。
Heavy metals' interactions with plumbing materials are complicated due to the differential formation of biofilms within pipes that can modulate, transform, and/or sequester heavy metals. This research aims to elucidate the mechanistic role of biofilm presence on Lead (Pb) accumulation onto crosslinked polyethylene (PEX-A), high-density polyethylene (HDPE), and copper potable water pipes. For this purpose, biofilms were grown on new pipes for three months. Five-day Pb exposure experiments were conducted to examine the kinetics of Pb accumulation onto the new and biofilm-laden pipes. Additionally, the influence of Pb initial concentration on the rate of its accumulation onto the pipes was examined. The results revealed greater biofilm biomass on the PEX-A pipes compared to the copper and HDPE pipes. More negative zeta potential was found for the biofilm-laden plastic pipes compared to the new plastic pipes. After five days of Pb exposure under stagnant conditions, the biofilm-laden PEX-A (980 μg m−2) and HDPE (1170 μg m−2) pipes accumulated more than three times the Pb surface loading compared to the new PEX-A (265 μg m−2) and HDPE pipes (329 μg m−2), respectively. However, under flow conditions, Pb accumulation on biofilm-laden plastic pipes was lower than on the new pipes. Moreover, with increasing the initial Pb concentration, greater rates of Pb surface accumulation were found for the biofilm-laden pipes compared to the new pipes under stagnant conditions. First-order kinetics model best described the Pb accumulation onto both new and biofilm-laden water pipes under both stagnant and flow conditions.