Pinto José N, Pereira Andreia, Silva Ana Rita R, Cardoso Diogo N, Mostafaie Amid, Campos Fábio, Rehan Iryna, Moreira Olga, Lopes Ivã Guidini, Murta Daniel, Afonso Alexandra, Oliveira Margarida, Silvério Karina S, Santos Maria Teresa, Carvalho Fátima, Almeida Adelaide, Loureiro Susana
Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal.
National Institute of Agricultural and Veterinary Research (INIAV)-Polo de Inovação da Fonte Boa, Vale de Santarém, 2005-424 Santarém, Portugal.
Toxics. 2025 Jul 30;13(8):648. doi: 10.3390/toxics13080648.
Olive mill wastewaters (OMWWs) are an environmental problem in the Mediterranean region, and it is crucial to explore strategies for their treatment and repurposing. The chemical precipitation technique (CPT) has been presented as a cost-effective wastewater treatment solution that might be applied to OMWW. The CPT-resulting precipitant subproducts (sludge) may be reprocessed (e.g., agricultural fertilizer and/or soil amendment), while the treated wastewater may be repurposed or reused (e.g., irrigation, aquaponic, or industrial processes). This study aimed to evaluate the efficacy of CPT in treating wastewater from the olive oil industry from an ecotoxicological perspective. Additionally, to assess the safe use of the obtained sludge in CPT treatment, its effects on soil biota were assessed. For this, a set of ecotoxicological assays using freshwater (, and ), terrestrial invertebrates ( and ), and plants ( and ) were used as model organisms. Results demonstrated that CPT reduced OMWW toxicity to freshwater organisms, offering a favorable outlook on CPT's potential as a wastewater treatment method. Increasing application rates of sludge in soil reduced the shoot biomass and the hydric content of both plants compared to the control. Survival of and was not affected by sludge in soil at any tested application rate, yet sludge application negatively affected the reproduction of both species, even at relevant sludge application rates (2%) of sludge in soils. Overall, the applicability of this sludge obtained by the CPT treatment in soils should be carefully evaluated due to the observed adverse effects on soil biota. Although the results of CPT were promising in reducing the toxicity of OMWW for these aquatic species, some adjustments/improvements should be performed to improve this technique and use all the obtained resources (treated water and sludge) in a fully circular perspective.
橄榄果渣废水（OMWWs）是地中海地区的一个环境问题，探索其处理和再利用策略至关重要。化学沉淀技术（CPT）已被提出作为一种具有成本效益的废水处理解决方案，可应用于OMWW。CPT产生的沉淀副产物（污泥）可进行再加工（如作为农业肥料和/或土壤改良剂），而处理后的废水可进行再利用或回用（如用于灌溉、水培或工业生产过程）。本研究旨在从生态毒理学角度评估CPT处理橄榄油工业废水的效果。此外，为评估CPT处理中所得污泥的安全使用情况，评估了其对土壤生物群的影响。为此，使用了一组以淡水生物（、和）、陆生无脊椎动物（和）以及植物（和）为模式生物的生态毒理学试验。结果表明，CPT降低了OMWW对淡水生物的毒性，这为CPT作为一种废水处理方法的潜力提供了良好前景。与对照相比，土壤中污泥施用量的增加降低了两种植物的地上部生物量和含水量。在任何测试施用量下，土壤中的污泥均未影响和的存活率，但污泥施用对这两个物种的繁殖均产生了负面影响，即使在土壤中污泥的相关施用量（2%）下也是如此。总体而言，由于观察到CPT处理获得的污泥对土壤生物群有不利影响，因此应仔细评估该污泥在土壤中的适用性。尽管CPT在降低OMWW对这些水生物种的毒性方面的结果很有前景，但仍应进行一些调整/改进，以完善该技术，并从完全循环的角度利用所有获得的资源（处理后的水和污泥）。
