Marine microplastics as vectors of major ocean pollutants and its hazards to the marine ecosystem and humans

Abstract

Microplastic pollutes water, land, air, and groundwater environments not only visually but also ecologically for plants, animals, and humans. Microplastic has been reported to act as vectors by sorbing pollutants and contributing to the bioaccumulation of pollutants, particularly in marine ecosystems, organisms, and subsequently food webs. The inevitable exposure of microplastic to humans emphasises the need to review the potential effects, exposure pathways, and toxicity of microplastic toward human health. Therefore, this review was aimed to reveal the risks of pollutant sorption and bioaccumulation by microplastic toward humans, as well as the dominant types of pollutants sorbed by microplastic, and the types of pollutants that are bioaccumulated by microplastic in the living organisms of the marine ecosystem. The possible factors influencing the sorption and bioaccumulation of pollutants by microplastic in marine ecosystems were also reviewed. The review also revealed the prevailing types of microplastic, abundance of microplastic, and geographical distribution of microplastic in the aquatic environment globally. The literature review revealed that microplastic characteristics, chemical interactions, and water properties played a role in the sorption of pollutants by microplastic. The evidence of microplastic posing a direct medical threat to humans is still lacking albeit substantial literature has reported the health hazards of microplastic-associated monomers, additives, and pollutants. This review recommends future research on the existing knowledge gaps in microplastic research, which include the toxicity of microplastic, particularly to humans, as well as the factors influencing the sorption and bioaccumulation of pollutants by microplastic.

COVID-19 Impacts on Beaches and Coastal Water Pollution at Selected Sites in Ecuador, and Management Proposals Post-pandemic

“…Just a few days before the lockdown, on March 7, 2020, 250 g were collected, but by September there was almost no plastic found (Supplementary Material Photo 1, lower panel). The impact of plastics on marine ecosystems is clearly recognized, e.g., (Santander-Rodriguez, 2017); Amelia et al (2021) have reviewed the impact of microplastic on marine ecosystems organism (food web). The range of plastics found is given in the results.…”

“…Recently, Quilliam et al (2020) and Randazzo et al (2020) have reported the COVID-19 virus in feces and domestic residual waters, and thus Larsen and Wigginton (2020), and Medema et al (2020) have proposed to correlate the presence of SARS-Coronavirus-2 RNA in Sewage with reported COVID-19. The impact from untreated wastewater on the marine environment and the whole trophic chain (Karen, 2019;Amelia et al, 2021) is a wellknown fact.…”

Study of Microplastics and Inorganic Contaminants in Mussels from the Montenegrin Coast, Adriatic Sea

“…Additionally, the analysis revealed a moderate level of variability of the trace metal contents among the three locations, as well as various types of MPs, which could, in principle, act as metal vectors. With respect to the latter point, various authors studied the relationship between trace metal contents and MPs in mussels and other bivalves, and concluded that MPs could act as metal ingress vectors [13,60,61]. However, some of them indicated that the entrance of Hg in mussels was facilitated due to the MPs, but the Hg elimination rate was also higher than in the case of other pathways [60,61].…”

“…They are also known for their bioconcentration ability, since they cannot regulate individual concentrations of metals [11] or other pollutants, for instance, MPs [9]. Moreover, different harmful contaminants, such as persistent organic pollutants (POPs) and trace metals, can be adsorbed on the MPs hydrophobic surface, so that MPs ingestion can contribute to higher uptake levels of other contaminants as well [8,12,13]. Thus, to identify the mussel exposure routes to a specific pollutant, it is important to analyze all possible vectors of the pollutant's specific uptake in the mussel tissues.…”

“…In particular, Raman spectroscopy can be successfully used to identify and analyze different compounds in marine organisms. Indeed, analysis of MPs in mussels and other marine samples is increasingly performed using Raman spectroscopy alone or in combination with Fourier-transform infrared (FTIR) spectroscopy [6,13,17]. However, Raman analysis and imaging have some specific advantages with respect to FTIR spectroscopy, such as better spatial resolution, wider spectral coverage, narrower spectral bands, higher sensitivity to non-polar functional groups, and lower water interference.…”