REVIEW ARTICLE | July 17, 2021
Heavy Metal Pollutions in Soil: Sources, Speciation and Remediations; Review
Yohannse Habteyesus Yitagesu
Page no 57-65 |
10.36348/sijb.2021.v04i06.001
The level of heavy metals above the permissible limit is toxic to human being as well as to animal welfare. The heavy metals enter the surrounding environment by natural and though anthropogenic activities. Soil erosion, natural weathering, mining, industrial effluents, urban runoff, sewage discharge, inorganic fertilizers, insecticides, herbicides, industrial emissions and transportations are some of the various sources of heavy metals induced to the environment, waterbody, soil and foods. Many instrumental analytical methods may be employed to measure the concentration of heavy metals in various samples. The most common techniques are atomic absorption spectrometry (AAS); atomic emission/ fluorescence spectrometry (AES/AFS); inductively coupled plasma mass spectrometry (ICP-MS); inductively coupled plasma optical emission spectrometry (ICP-OES); neutron activation analysis (NAA), X-ray fluorescence (XRF); and anodic striping voltammetry (AVS). The detection level of metals quantification depends on the instrument, method extractions and speciation. There are physical, chemical and biological techniques of heavy metals remediations in soil and human bodies. Biochar is one of the organic materials reduce the level of heavy metals, the plant species such as: Salix spp. (Salix viminalis, Salix fragilis), Castor (Ricinus communis), Corn (Zea mays),Populus spp. (Populus deltoides, Populus nigra, Populus trichocarpa), Jatropha (Jatropha curcas L.), Populus deltoides, Brassica juncea, Astragalus bisulcatus, Populus canescens can also remediate heavy metals from the contaminated soil. Chelate therapy ridding the body heavy metals with a chemical like Ethylene Diamine Tetraacetic Acid (EDTA) effective chelation of removing metals from body blood. Due to the increasing trend of HMs contamination, the negative impact on plants, environments and other organisms, it is important to mitigate the toxicity by developing effective and environmentally safe technologies. This paper therefore gives highlights of heavy metals sources, techniques of analysis and remediations.