Microplastic Pollution in Marine Environment: Occurrence, Fate …
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In addition to the above factors, the different terrain environment will also affect
the transport of microplastics. Many studies have shown that sea winds in open
coastal zones cause strong dispersal and transport of microplastics to the deep sea,
while in semi-enclosed areas they cause strong trapping and enrichment in sediments
[17].
Compared to the overlying water, there are large amounts of microplastics in
sediments at the bottom of the ocean. Many studies have shown that microplastics
in marine sediments account for 80% of the total content of marine microplastics.
Numerous studies have generally agreed that sediment is the ultimate destination of
microplastics [15]. Compared with the commonly believed transport of microplastics in an aquatic environment, the increasing number of studies have shown that
atmospheric transport [18] has become one of the important means of migration and
transport of microplastics to remote marine environments, such as deep sea or polar
regions, and will have a profound impact on the marine ecological environment [19].
The transport of microplastics in the ocean depends not only on natural factors
but also on biological factors. In earlier studies, seabirds have been identified as
vectors of chemical pollutants from the terrestrial environment to the marine environment. More recently, Radisic et al. [17] reported that seabirds may be vectors
of microplastic contamination in marine sediment environments by feeding on
microplastic-enriched organisms and then sinking microplastic-containing feces into
the sediment by excreting them [17].
Microplastics not only have biotoxicity, bio-accumulation, but also have unique
properties. They are carriers of persistent organic pollutants or biological pathogens
[20], thus causing harm to the marine environment. Recently, several studies have
shown that microplastics may be the carrier of harmful pollutants (i.e., hydrophobic
organic compounds, chemical additives, pathogens) [21]. When ingested by lowlevel microorganisms, microplastics can be enriched into a higher level of marine
organisms through the food chains and eventually enter the human body, causing
harm to human health. In addition, the additives contained in microplastics will also
be released into the marine environment during the aging process, causing physiological toxicity to marine organisms [22]. The additive, which is in microplastics,
interacts with the organic pollutants that are adsorbed on its surface, enhancing
toxicity. Some studies have shown that microplastics can transfer pollutants into
organisms [23]. Bowley et al. [20] have reported that marine microplastics can not
only carry potentially toxic fish pathogens, but also carry potential human pathogens
and act as carriers for these pathogens to be transported in the marine environment
[20]. Studies have presented that the toxic pollutants polychlorinated biphenyl show
relatively obvious adsorption affinity on PET and PS, and are easy to enter the marine
ecosystem through microplastics.
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In addition to the above factors, the different terrain environment will also affect
the transport of microplastics. Many studies have shown that sea winds in open
coastal zones cause strong dispersal and transport of microplastics to the deep sea,
while in semi-enclosed areas they cause strong trapping and enrichment in sediments
[17].
Compared to the overlying water, there are large amounts of microplastics in
sediments at the bottom of the ocean. Many studies have shown that microplastics
in marine sediments account for 80% of the total content of marine microplastics.
Numerous studies have generally agreed that sediment is the ultimate destination of
microplastics [15]. Compared with the commonly believed transport of microplastics in an aquatic environment, the increasing number of studies have shown that
atmospheric transport [18] has become one of the important means of migration and
transport of microplastics to remote marine environments, such as deep sea or polar
regions, and will have a profound impact on the marine ecological environment [19].
The transport of microplastics in the ocean depends not only on natural factors
but also on biological factors. In earlier studies, seabirds have been identified as
vectors of chemical pollutants from the terrestrial environment to the marine environment. More recently, Radisic et al. [17] reported that seabirds may be vectors
of microplastic contamination in marine sediment environments by feeding on
microplastic-enriched organisms and then sinking microplastic-containing feces into
the sediment by excreting them [17].
Microplastics not only have biotoxicity, bio-accumulation, but also have unique
properties. They are carriers of persistent organic pollutants or biological pathogens
[20], thus causing harm to the marine environment. Recently, several studies have
shown that microplastics may be the carrier of harmful pollutants (i.e., hydrophobic
organic compounds, chemical additives, pathogens) [21]. When ingested by lowlevel microorganisms, microplastics can be enriched into a higher level of marine
organisms through the food chains and eventually enter the human body, causing
harm to human health. In addition, the additives contained in microplastics will also
be released into the marine environment during the aging process, causing physiological toxicity to marine organisms [22]. The additive, which is in microplastics,
interacts with the organic pollutants that are adsorbed on its surface, enhancing
toxicity. Some studies have shown that microplastics can transfer pollutants into
organisms [23]. Bowley et al. [20] have reported that marine microplastics can not
only carry potentially toxic fish pathogens, but also carry potential human pathogens
and act as carriers for these pathogens to be transported in the marine environment
[20]. Studies have presented that the toxic pollutants polychlorinated biphenyl show
relatively obvious adsorption affinity on PET and PS, and are easy to enter the marine
ecosystem through microplastics.