Microplastics: impacts on corals and other reef organisms

Abstract

Plastic pollution in a growing problem globally. In addition to the continuous flow of plastic particles to the environment from direct sources, and through the natural wear and tear of items, the plastics that are already there have the potential to breakdown further and therefore provide an immense source of plastic particles. With the continued rise in levels of plastic production, and consequently increasing levels entering our marine environments it is imperative that we understand its impacts. There is evidence microplastic and nanoplastic (MNP) pose a serious threat to all the world's marine ecosystems and biota, across all taxa and trophic levels, having individual- to ecosystem-level impacts, although these impacts are not fully understood. Microplastics (MPs; 0.1–5 mm) have been consistently found associated with the biota, water and sediments of all coral reefs studied, but due to limitations in the current techniques, a knowledge gap exists for the level of nanoplastic (NP; <1 µm). This is of particular concern as it is this size fraction that is thought to pose the greatest risk due to their ability to translocate into different organs and across cell membranes. Furthermore, few studies have examined the interactions of MNP exposure and other anthropogenic stressors such as ocean acidification and rising temperature. To support the decision-making required to protect these ecosystems, an advancement in standardised methods for the assessment of both MP and NPs is essential. This knowledge, and that of predicted levels can then be used to determine potential impacts more accurately.

Artificial reefs through additive manufacturing: a review of their design, purposes and fabrication process for marine restoration and management

“…Conversely, polymers are well-known to accumulate in sediments, forming microplastics that adversely affect ingestion and egestion processes in marine biota (Huang et al , 2021; Pantos, 2022). This leads to the potential degradation and consequent production of marine debris, contributing to environmental pollution (Boström-Einarsson et al , 2020).…”

The role of plastics in the accumulation and release of trace elements in the environment

“…Once released into the environment there is a continuous flow of plastics between air, soil, biota, surface water, groundwater and sediments (Li et al, 2020). Major transport mechanisms include water cycling, deposition, wind erosion, incomplete incineration of plastic waste, wave action and sea turbulence, and interactions with biota (Ryan, 2015;Dris et al, 2017;Allen et al, 2020;Prinz and Korez, 2020;Watt et al, 2021;Weiss et al, 2021;Pantos, 2022). The transport of plastics can be affected by the density and the additives present, as well as the size and morphotype of each individual particle (Hoellein et al, 2019;Kumar et al, 2021;Shamskhany et al, 2021).…”

Plastic pollution of four understudied marine ecosystems: a review of mangroves, seagrass meadows, the Arctic Ocean and the deep seafloor

“…This selection was based (1) on our expertise and (2) the fact that these ecosystems have received less attention than, e.g. coral reefs, which have been the subject of hundreds of publications about plastic pollution and its effects (reviewed in [6,10,[24][25][26][27][28]). We further included the deep sea floor, which may not be threatened yet, but where research points towards increasing disturbances due to man-made impacts, and which due to logistical reasons also remains understudied.…”