Simultaneous removal of toxic metals by washing and soil enrichment with organic by‑products in a closed process

Gluhar, Simon (author), Kaurin, Anela (author), Zupanc, Vesna (author), Gantar, Anja (author), Fojkar, Barbara (author), Leštan, Domen (author)

A novel approach to soil remediation has been developed in which soil washing and the addition of organic by-products are carried out simultaneously in a single step. This method was tested on soil contaminated with Cd, Pb and Zn. The soil was washed in batches (35 kg soil/batch) with ethylenediaminetetraacetate (Na-, Ca-EDTA), sulfuric acid, and the reducing agent Na-dithionite, while organic by-products such as chicken manure, spent mushroom substrate, and corn cobs (2–5%) were mixed homogeneously into the soil. Results showed that this approach not only removed significant amounts of contaminants (58% Cd, 61% Pb and 12% Zn), but also improved soil properties, including increasing the amount of plant-available water, reducing leaching of residual toxic metals, reducing uptake of toxic metals in Brassica juncea and increasing β-glucosidase and dehydrogenase activity. The addition of organic by-products also prevented the accumulation of Na in the process after a series of batches and enabled the recycling (ReSoil® method) and continuous reuse of EDTA and the process solutions. However, the treatment also had a negative impact on plant growth, reducing the growth of Brassica juncea by 44%. Overall, this innovative approach is promising for effective and sustainable soil remediation, but further research is needed to optimize the process and minimize its impact on plant growth.

• Language: English
• Keywords: čiščenje tal, toksične kovine, pranje tal, onesnažena tla, remediacija
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 18 str.
• Numbering: Vol. 23, art. 452
• PID: 20.500.12556/RUL-182604
• UDC: 502.1
• ISSN on article: 1735-1472
• COBISS.SI-ID: 278579971
• Publication date in RUL: 19.05.2026

Record is a part of a journal

• Title: International journal of environmental science and technology
• Shortened title: Int. j. environ. sci. technol.
• Publisher: Iranian Society of Environmentalists, Center for Environment and Energy Research and Studies
• ISSN: 1735-1472
• COBISS.SI-ID: 516000281

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: chelator recycling, contaminated soil, remediation, slurry, soil improvement

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: J4-60071
• Name: Remediacija z bakrom onesnaženih tal v zaprtem krožnem procesu kot trajnostna rešitev v vinogradništvu

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P4-0085
• Name: Agroekosistemi