REVIEW PAPER
Environmental Safety and Security Investigations
of Neustonic Microplastic Aggregates Near
Water-Air Interphase
More details
Hide details
1
International Clean Water Institute, Manassas, VA USA, Riga Technical University, Kalku Street, Riga, Latvia,
and Ghitu Institute of Electronic Engineering and Nanotechnologies, Academiei str., 3/3, Chisinau, Moldova
2
National University of Food Technologies, 68 Volodymyrska Str., Kyiv 01601, Ukraine
Submission date: 2020-09-30
Final revision date: 2020-11-20
Acceptance date: 2020-12-25
Online publication date: 2021-06-07
Publication date: 2021-07-07
Pol. J. Environ. Stud. 2021;30(4):3457-3469
KEYWORDS
TOPICS
ABSTRACT
Scientific and public concerns due to presence of microplastic debris in the marine and freshwater
environment is fueling concerns of its impact on aquatic ecosystems and public health. Major sources
of water-polluting microplastics are polyethylene and polypropylene, as they aggregate near the waterair
interphase. Such neustonic hydrophobic cells attract spores of bacteria causing adverse impact
on the environmental, health and food supply chain. The objectives of this review investigation were
to (a): evaluate the concentration of microplastics with the sizes less 100 μm floating near the waterair
interphase; (b): develop a phenomenological model to study fate and transport of microplastics;
(c): analyze microbial coatings, and (d): assess potential impacts of biofilm-coated neustonic microplastics
on environment. A thorough review of microplastic pollution in marine environment was conducted
in terms of its size distribution, toxicity and toxicokinetic pathways. Since biofilms coated microplastics
float near the surface, hydrophobic cells of bacteria typically concentrate within a few micrometers
layer of water-air interphase. To develop a phenomenological model of neustonic floating biofilm-coated
microplastics, samples with the size of less than 100 μm were collected from within a few millimeters
near the water-air interphase and were subsequently concentrated using microfiltration of water
samples for analysis. Results of the optical scan of hexadecane and bacterial cells formed on vertically
submerged microscope slides near water-air interphase are presented. Additionally, microplastics near
a thin layer of water-air interphase were investigated using scanning electron microscopy, fluorescent
microscopy, flow cytometry, and particle analyzers. Since, hydrophobic and putative pathogenic bacteria
are attached to water surface, which dominate near water-air interphase, biofilm-coated microplastics
are more attractive for consumption by aquatic species than pure microplastics, which significantly
increases negative impacts of microplastics on aquatic ecosystems and public health through foodchain
supply. We conclude that it is critical to extend this investigation to include safety in terms of aquatic ecotoxicity, security, risk assessment, life-cycle analysis, upcycling of plastics and policy
recommendation on this new category of water pollutant.