Seven 21st century challenges of arsenic-fluoride contamination and remediation

Arsenic (As) and Fluoride (F) are two commonly occurring geogenic contaminants in groundwater environment, causing a range of carcinogenic and non-carcinogenic adverse health effects worldwide. Several studies have been conducted in past and many are ongoing to address As and F contamination issue of natural water. This special issue is conferring in recent times one of the emerging fields of science regarding co-occurrences of multi-contaminants within a given system and associated health risks. This special issue is divided into three sections. Section I deals with the occurrence and co-existence of As, F, and trace elements (TE) in the environment. As and F occurrence [including trace elements (TEs)] in groundwater at a global scale (example: India, Sri Lanka, Bangladesh, Ghana, and Iran, etc.) has been highlighted (Section I). The geological, and anthropogenic factors affecting As and F contamination have been observed. The state-of-art, removal techniques for As and F have been discussed. Section II and Section III incorporate all the advanced removal methods for As and F, respectively. Arsenic and F removal comprises assessing natural remediation potential (phytoremediation) including different advanced absorbents. The new findings published here, bring together a wide range of new insights on As and F behavior in the groundwater environment.