A review on occurrences, eco-toxic effects, and remediation of emerging contaminants from wastewater: Special emphasis on biological treatment based hybrid systems

The ubiquitous presence of emerging contaminants (ECs), such as pharmaceutically active compounds, personal care products, pesticides, endocrine-disrupting chemicals, etc., in the aquatic environment and their harmful impacts on the biosphere, is a global concern. Subsequently, removal of these persistent and eco-toxic compounds from wastewater is also a significant thrust area in environmental management. This paper presents an overview of genesis, pathways, and eco-toxicological effects of various ECs, and their management practices as well. The presence of many of these pernicious compounds in different regions across the globe is observed with a concentration exceeding the predicted no-effect concentration and calculated drinking water equivalent limit. Given the limitations of the conventional biological system concerning the recalcitrant and biocide nature of many of the ECs, the advanced biological system coupled with physical and chemical processes is emerging as the promising treatment option. Here, the performance analysis of several biological processes as well as the integrated treatment systems are extensively conducted highlighting their design and operational parameters, removal mechanisms, and criticality in hybridization techniques targeting the enhanced ECs removal. Among them, a combination of biological-chemical systems has shown better performance for the removal of ECs even achieving a complete removal in field scale systems. The present review catalyzes the research and its application in the real-life scenario for the treatment and management of ECs and brings forth a pragmatic solution to the policymakers and water engineers.

Automated summary

The presence of emerging contaminants in the aquatic environment poses global concerns due to their harmful impacts on the biosphere. Efforts to remove these compounds from wastewater have become a significant focus in environmental management. Advanced biological systems coupled with physical and chemical processes are emerging as promising treatment options, especially in regions where concentrations of harmful compounds exceed safe levels.