Magnetic nanomaterials for preconcentration and removal of emerging contaminants in the water environment

Abstract

Along with the increasingly detected drug residues, pharmaceutical products, personal care products, pesticides, herbicides, etc., in the water environment, there is an increasing concern over water pollution caused by these emerging contaminants (ECs) that are not regulated under current environmental laws. Their impacts on the environment and human health are poorly understood despite their trace concentrations (usually at pg/L, ng/L, or µg/L) in the natural environment. This is because ECs in real water systems may transform into multiple metabolite compounds; they might change properties (chemical/physical) when there are any changes in their surrounding conditions (pH, temperature, etc.). The use of nano-scaled magnetic materials is quite popular due to their flexibility to be modified and separation convenience via an external magnetic force. When nano-scaled magnetic materials are applied in solid-phase extraction (SPE), a preconcentration/sample preparation method (magnetic solid-phase extraction, M-SPE) with satisfactory analytical features is developed. M-SPE is widely explored and developed to serve as an integral efficient analytical tool for environmental monitoring of ECs, particularly for wastewater samples discharged from residential, hospital, and pharmaceutical industrial areas. Likewise, nano-scaled magnetic materials have also been used in many investigational studies on removing ECs. The role and effectiveness of nano-scaled magnetic materials in treating ECs via adsorption and photocatalytic degradation are discussed.