Reliability and stability of immobilization remediation of Cd polluted soils using sepiolite under pot and field trials

• Published in: Environmental pollution (1987) Vol. 208; no. Pt B; pp. 739 - 746
• Main Authors: Sun, Yuebing, Xu, Yi, Xu, Yingming, Wang, Lin, Liang, Xuefeng, Li, Ye
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.2016
• Subjects: Biodegradation, Environmental; Cadmium - analysis; Cadmium - chemistry; Cadmium - metabolism; Environmental Restoration and Remediation - methods; Enzyme activity; Immobilization remediation; Magnesium Silicates - chemistry; Microbial community; Reliability and stability; Reproducibility of Results; Soil - chemistry; Soil Microbiology; Soil Pollutants - analysis; Soil Pollutants - chemistry; Spinacia oleracea - drug effects; Spinacia oleracea - growth & development; Spinacia oleracea - metabolism; Cd; Enzyme activity; Reliability and stability; Microbial community; Immobilization remediation
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2015.10.054

Long-term effectiveness and persistence are two important criterias to evaluate alternative remediation technology of heavy metal polluted soils. Pot and field studies showed addition of sepiolite was effective in immobilizing Cd in polluted soils, with significant reduction in TCLP extracts (0.6%–49.6% and 4.0%–32.5% reduction in pot and field experiments, respectively) and plant uptake (14.4%–84.1% and 22.8%–61.4% declines in pot and field studies, correspondingly). However, the applications of sepiolite offered a limited guarantee for the safety of edible vegetables in Cd-polluted soils, depending on the soil type, the Cd pollution type and level, and the dose and application frequency of chemical amendments. Bioassays, such as plant growth, soil enzymatic activities and microbial community diversity, indicated a certain degree of recovery of soil metabolic function. Therefore, sepiolite-assisted in situ remediation is cost-effective, environmentally friendly, and technically applicable, and can be successfully used to reduce Cd enter into the food chain on field scale. •Sepiolite has reliability and stability for remediation of contaminated Cd.•Sepiolite significantly decreases Cd bioavailability in soil and uptake in plant.•The treatment of sepiolite improves soil quality. Sepiolite not only decreased soil Cd bioavailability and plant Cd uptake, but also improved soil quality.