Leakage of surfactants in greywater: Environmental impact, mitigation, and their circular economy

Globally, grey wastewater management is potently mismanaged in developing countries, which is a threat to circular economy. In order to address two significant challenges, water scarcity and water management, this literature study intends to offer insightful information on the environmental impact and mitigation of surfactants present in greywater. The present review focuses on the recent advancements made in eliminating surfactants from greywater through various techniques such as adsorption, ultrafiltration, biodegradation, and biomembrane separation. Despite these advancements, the complete elimination of surfactants remains a substantial and unresolved challenge. To address this widening gap in wastewater management, the present study also emphasizes the urgent implementation for alternative strategies through the reuse of both treated and untreated greywater. Additionally, it emphasizes the specific influence of surfactants on plant growth and productivity. It explores the potential of greywater as a nutrient source for crop cultivation in both terrestrial and extraterrestrial environments, using techniques such as aeroponics. It further delves into the aspects associated with the establishment of an aeroponic module for crop cultivation using GW, highlighting the importance of optimizing module design by considering various operational parameters, with a focus on surfactant-related factors such as concentration and type. However, the adoption of safe greywater reuse in irrigation and cultivation continues to face many challenges and criticism, which have been further elucidated in this review.