Environmental Chemistry and Toxicology Research Group, Department of Environmental and Occupational Studies, Faculty of Applied Sciences, Cape Peninsula University of Technology, Bellville, South Africa.
Federal Ministry of Education, Federal Secretarial Phase III, Abuja, FCT, Nigeria.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2021;56(14):1480-1489. doi: 10.1080/10934529.2021.2009730. Epub 2021 Dec 6.
The management and quality monitoring of wastewater have an important role in sustainable development. A recent approach in environmental protection involves the ecotoxicological assessment of effluents to complement the usual chemical evaluations. This study assessed the impacts of wastewater treatment plant (WWTP) effluent quality in a location in Western Cape province, South Africa using organisms that bear different ecosystem-level function responsibilities like the microalgae), crustaceans), and protozoan) in addition to the physicochemical parameters. The effluent showed values of chemical oxygen demand (COD; 41-83 mg L), dissolved oxygen (DO; 2.7-3.1 mg L), Redox potential (189-265 mV), and total dissolved solids (TDS; 656-718 ppm). The protozoan ecotoxicity test exhibited toxic effects of the effluents within 24-h with a mean lethal value (LC) of 1.12% for the winter season. The findings of this study revealed that analyzed physicochemical parameters are within the regulatory water quality acceptable standard thresholds with few exceptions, while the biotests were able to determine the toxicity levels and sensitivities of each test. The results showed that the WWTP whole effluent exerted toxicity to test organisms, but dilution can mitigate the effects considerably. The use of ecotoxicological assessment methods for municipal WWTP effluent may enhance existing water management strategies.
废水的管理和质量监测对可持续发展具有重要作用。环境保护的一个新方法是对废水进行生态毒理学评估，以补充通常的化学评估。本研究使用在不同生态系统层面承担功能责任的生物（如微藻类、甲壳类动物和原生动物），以及理化参数，评估了南非西开普省一个地点的废水处理厂（WWTP）废水的影响。废水显示出化学需氧量（COD；41-83mg/L）、溶解氧（DO；2.7-3.1mg/L）、氧化还原电位（189-265mV）和总溶解固体（TDS；656-718ppm）的值。原生动物的急性毒性试验在 24 小时内显示出废水的毒性作用，冬季季节的平均致死值（LC）为 1.12%。本研究的结果表明，分析的理化参数除了少数例外，均在可接受的监管水质标准范围内，而生物测试能够确定每个测试的毒性水平和敏感性。结果表明，整个 WWTP 废水对测试生物具有毒性，但稀释可以大大减轻其影响。将生态毒理学评估方法用于城市 WWTP 废水可能会增强现有的水管理策略。
