Vol.: (0123456789) 1 3 https://doi.org/10.1007/s10661-023-11890-7 REVIEW The bioaccessibility of adsorped heavy metals on bioflm‑coated microplastics and their implication for the progression of neurodegenerative diseases Ieshita Pan · Suganiya Umapathy · Praveen Kumar Issac · Md. Mostafzur Rahman · Ajay Guru · Jesu Arockiaraj Received: 27 May 2023 / Accepted: 16 September 2023 © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2023 Abstract Microplastic (MP) tiny fragments (< 5 mm) of conventional and specialized industrial polymers are persistent and ubiquitous in both aquatic and terres- trial ecosystem. Breathing, ingestion, consumption of food stufs, potable water, and skin are possible routes of MP exposure that pose potential human health risk. Various microorganisms including bacteria, cyanobac- teria, and microalgae rapidly colonized on MP surfaces which initiate bioflm formation. It gradually changed the MP surface chemistry and polymer properties that attract environmental metals. Physicochemical and environmental parameters like polymer type, dis- solved organic matter (DOM), pH, salinity, ion con- centrations, and microbial community compositions regulate metal adsorption on MP bioflm surface. A set of highly conserved proteins tightly regulates metal uptake, subcellular distribution, storage, and transport to maintain cellular homeostasis. Exposure of metal- MP bioflm can disrupt that cellular homeostasis to induce toxicities. Imbalances in metal concentrations therefore led to neuronal network dysfunction, ROS, mitochondrial damage in diseases like Alzheimer’s disease (AD), Parkinson’s disease (PD), and Prion dis- order. This review focuses on the bioflm development on MP surfaces, factors controlling the growth of MP bioflm which triggered metal accumulation to induce neurotoxicological consequences in human body and stategies to reestablish the homeostasis. Thus, the pre- sent study gives a new approach on the health risks of heavy metals associated with MP bioflm in which bio- flms trigger metal accumulation and MPs serve as a vector for those accumulated metals causing metal dys- biosis in human body. I. Pan (*) · S. Umapathy · P. K. Issac  Institute of Biotechnology, Department of Medical Biotechnology and Integrative Physiology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai 602105 Tamil Nadu, India e-mail: ieshitapan.sse@saveetha.com M. M. Rahman  Laboratory of Environmental Health and Ecotoxicology, Department of Environmental Sciences, Jahangirnagar University, Savar Dhaka-1342, Bangladesh M. M. Rahman  Department of Environmental Sciences, Jahangirnagar University, Savar Dhaka-1342, Bangladesh A. Guru (*)  Department of Cariology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai Tamil Nadu, India e-mail: ajayguru.sdc@saveetha.com J. Arockiaraj (*)  Toxicology and Pharmacology Laboratory, Department of Biotechnology, Faculty of Science and Humanities, SRM Institute of Science and Technology, Kattankulathur 603203, Chengalpattu District, Tamil Nadu, India e-mail: jesuaroa@srmist.edu.in / Published online: 2 October 2023 Environ Monit Assess (2023) 195:1264