Toward an Improved Understanding of the Ingestion and Trophic Transfer of Microplastic Particles: Critical Review and Implications for Future Research

Abstract

Microplastic particles have been observed in the environment and routinely detected in the stomachs and intestines of aquatic organisms over the last 50 yr. In the present review, information on the ingestion of plastic debris of varying sizes is collated, including data for >800 species representing approximately 87 000 individual organisms, for which plastic debris and microplastic particles have been observed in approximately 17 500, or 20%. The average reported number of microplastic particles/individual across all studies is estimated to be 4, with studies typically reporting averages ranging from 0 to 10 particles/individual. A general observation is that although strong evidence exists for the biological ingestion of microplastic particles, they do not bioaccumulate and do not appear to be subject to biomagnification as a result of trophic transfer through food webs, with >99% of observations from field‐based studies reporting that microplastic particles are located within the gastrointestinal tract. Overall, there is substantial heterogeneity in how samples are collected, processed, analyzed, and reported, causing significant challenges in attempting to assess temporal and spatial trends or helping to inform a mechanistic understanding. Nevertheless, several studies suggest that the characteristics of microplastic particles ingested by organisms are generally representative of plastic debris in the vicinity where individuals are collected. Monitoring of spatial and temporal trends of ingested microplastic particles could thus potentially be useful in assessing mitigation efforts aimed at reducing the emission of plastic and microplastic particles to the environment. The development and application of standardized analytical methods are urgently needed to better understand spatial and temporal trends. Environ Toxicol Chem 2020;39:1119–1137. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Quality Criteria for Microplastic Effect Studies in the Context of Risk Assessment: A Critical Review

“… 8 − 11 Their ubiquity in aquatic systems and their small size has resulted in concerns regarding their effects on aquatic biota for which ingestion has been observed at all levels of biological organization. 12 − 14 …”

The Story of Plastic Pollution: From the Distant Ocean Gyres to the Global Policy Stage

“…Finally, the widespread contamination of hundreds of species of wildlife across all trophic levels (Gall and Thompson, 2015), with evidence that plastics can be transported via trophic transfer (Provencher et al, 2019), demonstrates that organisms are also reservoirs and transporters of plastic pollution. Direct ingestion of large plastic debris (Gall and Thompson, 2015) and microplastics has been observed in hundreds of species and across many trophic levels (Gouin, 2020). Other routes of entry include uptake via the gills or indirect ingestion through the consumption of prey (Farrell and Nelson, 2013;Watts et al, 2014).…”

“…Degradation processes facilitate the breakup of one piece of plastic into many smaller pieces that may eventually become micro-and nanoplastics (Song et al, 2017). Smaller-sized plastics have different fates in the water column (Kooi et al, 2017) and in an organism (Gouin, 2020). A recent study demonstrated that carbon from microplastics mineralized and utilized by microbes was in turn used by phytoplankton and zooplankton in their cell membrane fatty acids (Taipale et al, 2019).…”

Assessment of plastic ingestion by pole‐caught pelagic predatory fish from O'ahu, Hawai'i

“…The ingestion of marine plastic debris (MPD) is a widespread and pervasive phenomenon globally (Cole, Lindeque, Halsband, & Galloway, 2011;Gall & Thompson, 2015;Gouin, 2020;Markic, Gaertner, Gaertner-Mazouni, & Koelmans, 2020), which has been documented in an increasing number of marine species, ranging from lower-trophic-consumers (e.g. gelatinous zooplankton ;Macali et al, 2018) to upper-trophic predators (e.g.…”

“…cetaceans ;Lusher et al, 2018). Multispecies assessments have documented MPD ingestion in commercially valuable fish species and their prey (Gouin, 2020;Markic et al, 2020). Yet, despite some recent comparative studies (Forrest & Hindell, 2018;Markic et al, 2018;Thiel et al, 2018), understanding of how plastic contamination of commercial fish species differs across the Pacific Ocean is inhibited by a lack of data for many regions and archipelagos.…”