Aix Marseille Université, CNRS, IM2NP, Université de Toulon, Toulon, France.
Laboratoire d'Ecologie, Biotechnologie et Santé (LEBS), Université Mouloud MAMMERI, PB 17, Tizi-Ouzou, RP, 15000, Algeria.
Environ Monit Assess. 2024 Aug 24;196(9):836. doi: 10.1007/s10661-024-12999-z.
This study evaluates the sustainability of spreading wastewater or sewage sludge on agricultural land, balancing benefits with contamination risks. Conventional ecological risk indices often fail to address the long-term accumulation of metals in soils. We investigate the feasibility of spreading based on current knowledge of potentially contaminating metals and their behavior in soil. We analyzed the speciation of metals (Ag, Cd, Co, Cr, Cu, Ni, Pb, Ti, Zn) through sequential extraction in sludge, treated wastewater, and soils after 14 years of application of sewage sludge and treated wastewater issued from an Algerian wastewater treatment plant. We introduce a Time to Critical Content Index (TCCI) that calculates the time required to reach critical levels of potentially mobile metals, considering total metal content and speciation. The TCCI takes into account product knowledge, soil characteristics, metal behavior, ecological/toxicological thresholds, and regulations. Applied to our case study, the TCCI indicates that spreading sewage sludge can continue despite metal contents exceeding regulatory ceiling values. The index serves as a precautionary measure, adaptable to evolving knowledge, providing a comprehensive framework for sustainable agricultural practices.
本研究评估了将废水或污水污泥施用于农业用地的可持续性，平衡了收益与污染风险。传统的生态风险指数往往无法解决土壤中金属的长期积累问题。我们根据当前对潜在污染金属及其在土壤中行为的了解，研究了推广的可行性。我们通过对污泥、处理后的废水以及在阿尔及利亚污水处理厂处理后的废水和污泥施用于土壤 14 年后进行的金属（Ag、Cd、Co、Cr、Cu、Ni、Pb、Ti、Zn）形态分析，对金属进行了分析。我们引入了时间到关键含量指数（TCCI），该指数考虑了总金属含量和形态，计算了达到潜在可移动金属临界水平所需的时间。TCCI 考虑了产品知识、土壤特性、金属行为、生态/毒理学阈值和法规。在我们的案例研究中，TCCI 表明，尽管金属含量超过了监管上限值，但仍可以继续施洒污水污泥。该指数作为一种预防措施，适应不断变化的知识，为可持续农业实践提供了一个全面的框架。
