A review on microplastics in landfill leachate: formation, occurrence, detection, and removal techniques

ABSTRACT

Plastic is a widely used material that provides numerous benefits to modern society. A major portion of plastic waste (PW) makes its way to landfills. Thermal deterioration, biodegradation, mechanical abrasion, and chemical oxidation are the major processes contributing to the weathering (from macro to micro/nano) of plastic debris in landfills. Literature has shown that landfills serve as receptacles for the accumulation of PW. However, landfill leachate (LL) as a potential source of environmental microplastics (MPs) has not gained considerable attention. The high surface area and hydrophobicity of MPs enhance their ability to be ingested by living organisms and, at the same time, increase their susceptibility to the sorption of organic contaminants, heavy metals, and pathogens. This paper systematically reviews LL as a source of MPs to the environment, the formation of MPs from PW in landfills, associated environmental risks, and detection techniques of MPs in LL. The manuscript also addresses possible solutions, emphasising recent technical advances in removing MPs from landfills and the associated challenges. Future perspectives and potential management solutions are also discussed in this paper.

GRAPHICAL ABSTRACT

KEYWORDS:

• Biological degradation of microplastics
• ecological risks of microplastics
• plastic waste
• removal of microplastics
• quantification of microplastics

Acknowledgement

All the authors acknowledge Director, CSIR-NEERI, for granting permission to publish the manuscript. The first author thanks the University Grants Commission (UGC) for providing financial assistance in the form of fellowship (UGC NET JRF-210510115261, Environmental Sciences).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by University Grants Commission: [Grant Number NET JRF-210510115261].

Notes on contributors

Ashish Dehal

Ashish Dehal has completed his B. Tech in Civil Engineering and M. Tech in Environmental science and Engineering. Currently, he is enrolled as a research scholar (JRF- Engineering Sciences) in “Academy of Scientific and Innovative Research” at the “Council of Scientific and industrial Research-National Environmental Engineering Research Institute (CSIR-NEERI)”. His interest lies in solid waste management, biomedical waste management, micropollutants, and greywater utilization. He has been a reviewer for the SCI-indexed Journal -Water Science and Technology (IWA publishing) since 2019.

Archana Prajapati

Archana Prajapati is an alumnus of MS University, Vadodara, where she successfully completed her bachelors and master's degree in Environmental Sciences. Currently, she is working as project associate in CSIR-National Environmental Engineering Research Institute (NEERI). She has 5 years of experience as project associate. Her interest lies in plastic waste management, microplastics and associated organic pollutants. She has been a reviewer for Soil and Sediment Contamination: An international Journal from 2023.

Mahendra P. Patil

Dr. Mahendra P. Patil is currently working as chief scientist and head of Chemical and Hazardous Waste Management Division and as an Associate Professor at the Academy of Scientific and Innovative Research in CSIR-National Environmental Engineering Research Institute. He has completed his PhD. from Nagpur University in chemical engineering. He has 25 years' experience on various aspects of solid and hazardous waste management. This includes waste characterization, reuse/recycle, waste minimization, treatment, disposal, assessment and remediation of waste contaminated sites.

A. Ramesh Kumar

Dr. A. Ramesh Kumar is currently working as a principal scientist in CSIR-National Environmental Engineering Research Institute and as an Associate Professor at the Academy of Scientific and Innovative Research. He has completed his PhD. from the University of Madras in analytical chemistry. He has four years of experience as a Scientist-C in ICMR-National Institute of Occupational Health and 16 years of experience as Asst. Chemist in Central Ground Water Board. He has authored numerous book chapters, research, and review articles. He is associate editor of the Journal of Indian Association for Environmental Management. He has also handled multiple projects sponsored by the private, government, and International academic/research bodies.