Arsenic in drinking water: overview of removal strategies and role of chitosan biosorbent for its remediation

Accessibility to clean drinking water often remains a crucial task at times. Among other water pollutants, arsenic is considered a more lethal contaminant and has become a serious threat to human life globally. This review discussed the sources, chemistry, distribution, and toxicity of arsenic and various conventional technologies that are in option for its removal from the water system. Nowadays, biosorbents are considered the best option for arsenic-contaminated water treatment. We have mainly focused on the need and potential of biosorbents especially the role of chitosan-based composites for arsenic removal. The chitosan-based sorbents are economically more efficient in terms of their, low toxicity, cost-effectiveness, biodegradability, eco-friendly nature, and reusability. The role of various modification techniques, such as physical and chemical, has also been evaluated to improve the physicochemical properties of biosorbent. The importance of adsorption kinetic and isotherm models and the role of solution pH and pH(PZC) for arsenic uptake from the polluted water have also been investigated. Some other potential applications of chitosan-based biosorbents have also been discussed along with its sustainability aspect. Finally, some suggestions have been highlighted for further improvements in this field.

Automated summary

This review discusses the sources, chemistry, distribution, and toxicity of arsenic, as well as various conventional technologies for its removal. It highlights the potential and application of biosorbents, particularly chitosan-based composites, for arsenic removal. The economic efficiency, low toxicity, biodegradability, eco-friendly nature, and reusability of chitosan-based sorbents make them an attractive option. The review also evaluates the role of modification techniques and the importance of adsorption kinetics and isotherm models in improving biosorbent properties.