Reducing Heavy Metals Extraction from Contaminated Soils Using Organic and Inorganic Amendments – a Review

Recently problems relating to environmental pollution and the need to protect and preserve the environment from further deterioration has drawn increasing research attention. The goal of any remediation based on soil amendments is to achieve maximum reduction in the bioavailability of heavy metals by immobilization in soils. Modern remediation approaches increasingly focus on in situ environment-friendly techniques. Different organic and inorganic amendments have been used to treat heavy metals-contaminated soils. These included municipal solid waste compost, biosolid compost, cow manure, sheep manure, sewage sludge, bark chips, woodchips, vegetable waste, vermicompost, red mud, lime, beringite, zeolites, charcoal, fly ash; and biochar etc. This review focuses on the effectiveness of soil amendments to reduce toxicity of heavy metals by reducing available fractions that may ultimately reduce the heavy metal transfer to plants.