Nanoscale zero-valent iron mediates Fe speciation-microbe synergism for simultaneous remediation of 2,3',4,4',5-pentachlorobiphenyl and Cd co-contaminated soil and safe rice production.

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Provides mechanistic insights into nZVI-mediated remediation of organic-metal co-contaminated soils, relevant for environmental remediation scientists.

🏢実務担当者:May inform remediation strategies for PCB and Cd contaminated agricultural soils, but limited direct applicability for corporate sustainability teams.

🏛政策担当者:Offers evidence for soil remediation technologies that could support safe food production, but not directly linked to climate policy.

Soil co-contamination with polychlorinated biphenyls (PCBs) and cadmium (Cd) threatens agricultural sustainability. Simultaneous remediation of these pollutants remains challenging due to their distinct physicochemical properties and divergent remediation pathways. Herein, we conducted a 140-day pot experiment to evaluate the efficacy of nanoscale zero-valent iron (nZVI) at doses of 50, 200, and 500 mg/kg for the simultaneous remediation of 2,3',4,4',5-pentachlorobiphenyl (PCB118, 2 mg/kg) and Cd (5 mg/kg), and its implications for safe rice production. After 140 days of treatment, soil residual PCB118 concentrations decreased from 0.46 mg/kg (control) to 0.42-0.31 mg/kg, and soil available Cd declined from 3.40 mg/kg (control) to 3.18-2.50 mg/kg. The core mechanism lies in the nZVI-induced formation of amorphous Fe, which not only facilitates PCB118 degradation via chemical catalysis and microbial metabolism but also drives the conversion of mobile Cd to stable Fe/Mn oxide-bound fractions through surface complexation and co-precipitation. Notably, 50-500 mg/kg nZVI treatments increased rice yield from 5.66 g/plant to 6.48-8.18 g/plant, while reducing the contents of PCB118 and Cd in grains from 0.033 mg/kg and 0.38 mg/kg to 0.012-0.025 mg/kg and 0.14-0.24 mg/kg, respectively. This outcome is attributed to two factors: the prominent enhancement of root Fe plaque formation mediated by nZVI (179.79-389.61 % of the control), which sequestered pollutants and limited their early uptake; and the sustained lower contaminant bioavailability within nZVI-amended soil during later growth stages. Ultimately, nZVI selectively enriches functional microbial taxa involved in Fe metabolism, Cd sequestration, and PCBs degradation, thereby establishing a regulatory network encompassing Fe transformation, microbial response, and pollutant remediation. This network enables both the simultaneous remediation of co-contaminations and the assurance of safe agricultural production.

• semanticscholar https://doi.org/10.1016/j.jhazmat.2026.141029first seen 2026-07-16 06:55:40