Polycyclic aromatic hydrocarbons (PAHs) pose a constant threat to the environment and public health. There are numerous activities in the Greater Cairo area that emit and release significant amounts of PAHs. Concentrations of these PAHs are released into the air and mixed with surface water, limiting its use. In this study, 17 PAH compounds are mapped at eight sites along the Nile River and its tributaries in Greater Cairo. In addition, their removal efficiency is evaluated with the conventional treatment in eight water treatment plants. PAHs were analyzed using GC-MS from January to December 2018. Naphthalene, anthracene, fluorene, pyrene, and phenanthrene were detected. The total amount of PAHs in raw water was highest in Shamal Helwan (1,325 ± 631 ng/l) and lowest in Mostorod (468 ± 329 ng/l), and the removal ranged from 25 to 31%. Further research is needed to integrate other techniques to reduce PAHs using the conventional treatment, and more efforts should be made to reduce the presence and release of PAHs in raw water.

中文翻译：

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大开罗供水系统中的多环芳烃 (PAH)。

多环芳烃 (PAH) 对环境和公众健康构成持续威胁。大开罗地区有许多排放和释放大量 PAH 的活动。这些 PAH 的浓度会释放到空气中并与地表水混合，从而限制了其使用。在这项研究中，在尼罗河及其在大开罗的支流的八个地点绘制了 17 种 PAH 化合物。此外，它们的去除效率通过八个水处理厂的常规处理进行评估。2018 年 1 月至 2018 年 12 月，使用 GC-MS 分析了 PAHs。检测到萘、蒽、芴、芘和菲。原水中 PAHs 的总量最高的是 Shamal Helwan (1,325 ± 631 ng/l)，最低的是 Mostorod (468 ± 329 ng/l)，去除率在 25% 到 31% 之间。