Abstract：
This study addresses the heightened global reliance on point-of-use (PoU) systems driven by water quality concerns, ageing infrastructure, and urbanization. While widely used in Egypt, there is a lack of comprehensive evaluation of these systems. We assessed 10 reverse osmosis point-of-use systems, examining physicochemical, bacteriological, and protozoological aspects of tap water (inlets) and filtered water (outlets), adhering to standard methods for the examination of water and wastewater. Results showed significant reductions in total dissolved solids across most systems, with a decrease from 210 ± 23.6 mg/L in tap water to 21 ± 2.8 mg/L in filtered water for PoU-10. Ammonia nitrogen levels in tap water decreased from 0.05 ± 0.04 to 2.28 ± 1.47 mg/L to 0.02 ± 0.04 to 0.69 ± 0.64 mg/L in filtered water. Despite this, bacterial indicators showed no significant changes, with some systems even increasing coliform levels. Protozoological analysis identified prevalent Acanthamoeba (42.5%), less frequent Naegleria (2.5%), Vermamoeba vermiformis (5%), and potentially pathogenic Acanthamoeba genotypes. Elevated bacterial indicators in filtered water of point-of-use systems, combined with essential mineral removal, indicate non-compliance with water quality standards, posing a public health concern. Further research on the long-term health implications of these filtration systems is essential.
摘要：
这项研究解决了由水质问题驱动的全球对使用点（PoU）系统的高度依赖，老化的基础设施，和城市化。虽然在埃及广泛使用，缺乏对这些系统的全面评估。我们评估了10个反渗透使用点系统，检查物理化学，细菌学，以及自来水（入口）和过滤水（出口）的原生动物方面，遵守水和废水检查的标准方法。结果显示，大多数系统的总溶解固体显著减少，PoU-10从自来水中的210±23.6mg/L降至过滤水中的21±2.8mg/L。自来水中的氨氮水平从0.05±0.04降至2.28±1.47mg/L，再到过滤水中的0.02±0.04至0.69±0.64mg/L。尽管如此,细菌指标无明显变化,有些系统甚至会增加大肠杆菌水平。原生动物分析确定了流行的棘阿米巴（42.5％），不太频繁的Naegleria(2.5%)，Vermamoebavermiformis（5%），和潜在的致病性棘阿米巴基因型。使用点系统过滤水中的细菌指标升高，结合必需的矿物质去除，表明不符合水质标准，引起公众的关注。对这些过滤系统的长期健康影响的进一步研究至关重要。
