A review on heavy metal pollution, toxicity and remedial measures: Current trends and future perspectives

Water is an exceptionally essential source for the presence of life on the earth. The water quality has seriously affected because of the overgrowth of the population, human activities, fast industrialization, unskilled utilization of natural water resources and unplanned urbanization. Heavy metal is a group of metal and metalloids with an atomic density higher than the 4000 kg/m(3). The heavy metals are toxic in nature which causes serious health illness to human beings and animals, even at very low concentration. These heavy metals enter into the aquatic system through the agricultural runoff and industrial discharges. Different treatment methods are available to remove the heavy metals from the aquatic environment with a different degree of success. In any case, the deficiencies of a large portion of these treatment methods are due to the production of secondary waste, high cost for operation and maintenance etc. Hence, it is important to develop robust, eco-friendly and economically viable treatment methods for the removal of heavy metals from the aquatic system and to safeguard the environment. In this review article, definite data on the source and their belongings of substantial metal contamination to the plants, individuals and other living life forms have been clarified. The distinctive sorts of treatment strategies for the removal of the toxic metals from wastewater had been explained. The numerous types of low-cost adsorbents utilized by different researchers/scientists for removal of heavy metals from wastewater have been discussed in detail. The recommendations for further scope of research which can be done have been discussed in detail. (C) 2019 Elsevier B.V. All rights reserved.