Occurrence of per- and polyfluorinated substances, microplastics, pharmaceuticals and personal care products as emerging contaminants in landfill leachate: A review

• Landfill leachate is a major source of emerging contaminants (EC) • EC levels are impacted by landfill characteristics and environmental factors • Short chain PFSAs and PFCAs are predominant in landfill leachate Emerging contaminants are prevalent in landfill leachate, known for their persistence and adverse health effects, posing significant challenges to the environment and public health. This review focuses on three main categories of emerging contaminants that have received growing attention: per- and polyfluoroalkyl substances (PFAS), microplastics, and pharmaceuticals and personal care products (PPCPs). Increased awareness of their prevalence in the environment has highlighted the need for comprehensive understanding. This paper thoroughly reviews the classification of these emerging contaminants and provides insights into the analytical methods used for their quantification, their occurrence in landfill leachate, and the remediation processes. Concentrations of these contaminants in landfill leachate range from a few nanograms per liter (ng/L) to hundreds of micrograms per liter (µg/L). These concentrations are influenced by factors such as landfill composition, age, waste decomposition stages, and environmental conditions. Despite advancements in understanding the occurrence of emerging contaminants in landfill leachate, significant knowledge gaps remain regarding their behavior and fate. Addressing these gaps through further research is essential for achieving a clearer understanding of the transformation pathways of emerging contaminants in landfill settings.