Abstract

Regular monitoring of the chemical status of water bodies remains crucial in countries where data on chemical fingerprints that can assist in environmental policy is still limited. The current study focused on the concentrations of 14 metals and their sources in two important South African rivers that pass through various rural areas and two semi-urban towns in the province of the Eastern Cape. Most of the essential metals were within the South African guidelines for domestic water use except for selenium and iron which reached the concentrations of 131 and 712 µg L⁻¹ that exceed the guideline values of 20 and 200 µg L⁻¹, respectively. Cadmium and lead were above the South African Water Quality Guidelines and World Health Organization limits of 3 and 10 µg L⁻¹, attaining the highest concentrations of 35 and 34 µg L⁻¹, respectively. The impact of the wastewater treatment plant effluent and the municipal dumpsite leachates on metal ion concentrations in the rivers was observed for some metals. The metals source was related to deterioration of galvanized corrugated steel sheets from scrap yards and dwellings made-out of galvanized corrugated sheets, as well as agricultural activities and natural geological processes. An overview of the current water quality status of the two rivers may serve as a basis for sink-oriented pollutant fingerprinting toward sustainable water sources for communities.

摘要

在有助于环境政策的化学指纹数据仍然有限的国家，定期监测水体的化学状况仍然至关重要。目前的研究重点关注流经东开普省各个农村地区和两个半城市城镇的两条重要的南非河流中 14 种金属的浓度及其来源。大多数必需金属都在南非家庭用水指南范围内，硒和铁除外，其浓度分别达到 131 和 712 µg L -1，超过了^{20和 200 µg L -1}的指南值。镉和铅高于南非水质指南和世界卫生组织 3 和 10 µg L ^{−1的限值，分别达到 35 和 34 µg L -1}的最高浓度。对于某些金属，观察了废水处理厂流出物和市政垃圾场渗滤液对河流中金属离子浓度的影响。金属来源与废品场和用镀锌波纹板制成的住宅中镀锌波纹钢板的劣化以及农业活动和自然地质过程有关。对这两条河流当前水质状况的概述可以作为以汇为导向的污染物指纹识别社区可持续水源的基础。