Abstract
In recent decades, the prevalence of plastics in the marine environment has
increased and is amongst the most pervasive problems affecting the marine
environment globally. Numerous studies have documented microplastic ingestion by
marine species with more recent investigations focusing on the secondary impacts of
microplastic ingestion on ecosystem processes. However, few studies so far have
examined microplastic ingestion by mesopelagic fish which are one of the most
abundant pelagic groups in the oceans and their vertical migrations are known to
contribute significantly to the rapid transport of carbon and nutrients to the deep sea.
Therefore, any ingestion of microplastics by mesopelagic fish may adversely affect this
cycling and may aid in the transport of microplastics from surface waters to the deep-sea benthos.
Microplastics are ubiquitous in the marine environment and are increasingly
contaminating species in the marine ecosystem and the food chain, including food
stuffs intended for human consumption. The effects of microplastics on aquatic
organisms are currently the subject of intense research. Here, we provide a critical
perspective on published studies of microplastic ingestion by aquatic biota. We
summarize the available research on Microplastic presence, behavior, and effects on
aquatic organisms monitored in the field and laboratory studies of the ecotoxicological
consequences of microplastic ingestion.
Finally, researchers plan further studies to learn more about how these fish are
ingesting and spreading microplastics. It will be particularly interesting to see whether
the fish ingest these microplastics directly as mistaken prey items, or whether they
ingest them through eating prey species, which have previously ingested the
microplastics. Also, there is a need to understand the mechanism of action and
ecotoxicological effects of environmentally relevant concentrations of microplastics on
aquatic organism health.