Water Challenges in South Asian Countries: A Focused Review on Emerging Nanomaterials and Technological Processes in Wastewater Treatment

Abstract

South Asia, the world's most populated region, is facing many environmental and healthcare challenges due to poor freshwater management/wastewater treatment. Most South Asian (SA) countries, such as India, Pakistan, Sri Lanka, and Bangladesh, are suffering from water pollution issues generated due to domestic and industrial effluents containing heavy/toxic ions, textile dyes, pharmaceuticals, bacteria/viruses inorganic/organic pollutants, etc. To overcome these challenges, extensive research is being carried out with an emphasis on technological development to maintain water sustainability. The present review discusses water pollution as well as various challenges in SA countries along with solutions through scientific research carried out by developing nanomaterials and technological wastewater treatment processes, i.e., photocatalytic/adsorptive removal, disinfection, tracing/sensing, etc. Particularly, syntheses of TiO 2 nanoparticles and graphene oxide (GO)-based nanomaterials which were found to be most extensively investigated in the SA region have been discussed with emphasis on their multifunctional applications using various water treatment processes, mechanisms, and synergetic effects. Eventually, various challenging issues and solution opportunities are discussed for future development to maintain water sustainability in SA countries.

Fingerprinting and Differentiation of Landfill Leachate and Domestic Sewage in Surface Water with Machine Learning Based Surface Enhanced Raman Spectroscopy

“…The information regarding the source and characteristics of a pollution incident is hiding in the receiving body of water. This is because the receiving water bodies served as “data loggers” by collecting chemical information from the watershed, namely the tremendous amount of dissolved inorganic and organic compounds. , If interpreted correctly, this chemical information could reveal not only the feature (formula of the pollutants, concentration, spatial distribution, etc. ), but also the source of the pollution.…”

In Situ Fabrication and Characterization of g-C3N4 onto Cellulose Nanofibers and Selective Separation of Heavy Metal Ions

“…The water pollution caused by organic and inorganic matters are categorized as a class 1 pollution. − Heavy metal pollution has become a major global environmental concern due to the element’s toxicity and requires serious attention. − Despite being present in trace amounts, they have detrimental effects on human health. , The US Environmental Protection Agency has set a limit of 2.0–10 ppb for the amount of various heavy metals that are present in drinking water . The World Health Organization (WHO) also recognizes their toxicity and promotes their removal, and monitoring their level in environmental water samples is one of its key priorities.…”