Arsenic: An Overview of Applications, Health, and Environmental Concerns and Removal Processes

Arsenic is a toxic element and has been responsible for many accidental, occupational, deliberate, and therapeutic poisonings since its discovery in 1250. It occurs in natural waters as the arsenite (As3+) and arsenate (As5+) ions. The solubility of arsenite and arsenate compounds is relatively high so that these ions are readily transported through aqueous routes into the environment. Arsenic can be transferred from soils to crops and accumulates in various food crops and aquatic plants. The fascinating chemistry and toxicity potential make arsenic and its compounds of particular scientific interest and environmental concern. The conventional removal of heavy metals from wastewater, natural waters, and drinking water has only limited effects on arsenic removal. In this review, the main engineering and medical applications, salient health and environmental concerns, novel research on treatment for arsenic poisoning, and removal technologies for arsenic and their derivatives are discussed and enumerated with a view to pursue valuable applied research in order to protect the environment from arsenic toxicity.