Feasting on microplastics: ingestion by and effects on marine organisms

Abstract

Ingestion of microplastics by marine organisms is a common occurrence in marine ecosystems, but the experimental demonstration of the effects of ingested microplastics on marine organisms has only recently become an important subject of research. In this review, the ingestion of microplastics by marine organisms, its attendant potential consequences and specific hypothetical questions for further studies are discussed. The formation of heteroaggregates in the gut of prey organisms may delay microplastic clearance, potentially increasing the chances of microplastic trophic transfer to predators. Also, the survival and energetics of keystone species at lower trophic levels are negatively affected by ingestion of microplastics, thereby raising questions about the transfer of energy and nutrients to organisms at higher trophic levels. Further, since microplastics are able to adsorb and concentrate organic pollutants up to 1 million times more than the pollutant concentration in ambient waters, the ingestion of such small plastic fragments is, a probable route for the entrance and biomagnification of toxic chemicals in the marine food web. However, the equilibrium state between pollutant concentration in marine organisms and that of surrounding waters makes it unclear whether the ingestion of microplastics actually increases the pollutant load of organisms. Finally, microplastic ingestion can cause endocrine disorders in adult fish, which could result in neoplasia via epigenetic programming. Therefore, microplastic pollution may be a contributory cause of increased incidents of neoplasia in marine animals. The amount of microplastics in marine waters will steadily rise, and questions about their impact on marine ecosystems will linger.

Microplastics of different characteristics are incorporated into the larval cases of the freshwater caddisfly Lepidostoma basale

“…The industrial mass production of plastics started in the 1940s (Cole et al 2011), and microplastics were reported in the oceans as early as the 1970s , Carpenter & Smith 1972. Since then, numerous studies have examined the impact of microplastics on marine organisms (Erren et al 2013, Wright et al 2013, Egbeocha et al 2018, including vertebrates (Germanov et al 2018) and invertebrates (Cole et al 2013, Kaposi et al 2014. Rivers are important sources of marine microplastics, as they transport plastic debris from inland waters to the ocean (Lebreton et al 2017).…”

Adapting to urban ecosystems: unravelling the foraging ecology of an opportunistic predator living in cities

“…The presence of plastics in birds has become common, and represents a serious danger to marine and terrestrial biodiversity (Derraik 2002). Plastic debris is often ingested by marine predators and can cause health disorders and even death (Egbeocha et al 2018). Given the high presence of plastics detected in the stomach content, probably present in the stomach of marine fish (Bellas et al 2016) or ingested directed by adults during the feeding events (Codina-García et al 2013), and the potential detrimental effects of plastic ingestion in seabirds, there is necessity to assess the magnitude of the effects of plastics on these birds (Wilcox et al 2015).…”

Micro-by-Micro Interactions: How Microorganisms Influence the Fate of Marine Microplastics

“…These foragers are stimulated by chemical signaling molecules and the biofilm may disguise the inert nature of the plastic particles making them similar to food items. Selective feeders, such as copepods and shrimps, which constitute an important trophic link from particulate material to higher consumers would be particularly discriminative (Egbeocha et al 2018). Indeed, some copepods, showed a preference for aged microbeads.…”