Environmental Safety and Security Investigations of Neustonic Microplastic Aggregates Near Water Air Interphase
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 mm 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 mm 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 *e mail: prof.vaseashta@ieee.org DOI: 10.15244/pjoes/131947 ONLINE PUBLICATION DATE: 2021 06 07 Vaseashta A. et al. 3458
Polish Journal of Environmental Studies