The ecotoxicological consequences of microplastics and co-contaminants in aquatic organisms: a mini-review

Abstract

Microplastics (MPs, <5 mm in size) are a grave environmental concern. They are a ubiquitous persistent pollutant group that has reached into all parts of the environment — from the highest mountain tops to the depths of the ocean. During their production, plastics have added to them numerous chemicals in the form of plasticizers, colorants, fillers and stabilizers, some of which have known toxicity to biota. When released into the environments, MPs are also likely to encounter chemical contaminants, including hydrophobic organic contaminants, trace metals and pharmaceuticals, which can sorb to plastic surfaces. Additionally, MPs have been shown to be ingested by a wide range of organisms and it is this combination of ingestion and chemical association that gives weight to the notion that MPs may impact the bioavailability and toxicity of both endogenous and exogenous co-contaminants. In this mini-review, we set the recent literature within what has been previously published about MPs as chemical carriers to biota, with particular focus on aquatic invertebrates and fish. We then present a critical viewpoint on the validity of laboratory-to-field extrapolations in this area. Lastly, we highlight the expanding ‘microplastic universe’ with the addition of anthropogenic particles that have gained recent attention, namely, tire wear particles, nanoplastics and, bio-based or biodegradable MPs, and highlight the need for future research in their potential roles as vehicles of co-contaminant transfer.

Toward Understanding the Environmental Risks of Combined Microplastics/Nanomaterials Exposures: Unveiling ZnO Transformations after Adsorption onto Polystyrene Microplastics in Environmental Solutions

“…Even though there are several examples in the scientific literature of MPs transporting a range of pollutants, [ 12 , 13 , 14 ] very few studies have focused on the transformations these nano‐ and micro‐pollutants may undergo when adsorbing to the MP surface. Even fewer have studied the interaction between microplastics and ZnO ENMs.…”

Ecotoxicological Impacts of Micro(Nano)plastics in the Environment: Biotic and Abiotic Interactions

“…The recent UNEP technical report "Chemicals in Plastics" [9] now notes "that more than 13,000 chemicals have been identified as associated with plastics and plastic production", of which, 3200 are known to be toxic. Once released, MNPs may sorb many other chemical groups (metals, pharmaceuticals and organic pollutants) and facilitate their transfer to biota [10][11][12], but knowledge gaps persist regarding the role of MNPs as chemical carriers, particularly when considering the vast array of polymer types, chemicals, environmental transformations, organisms and species-specific physiological parameters that interact with each other [11]. Adverse outcomes from plastic exposure are shared cross-species, indicating common mechanisms of toxicity.…”

Editorial: Plastic pollution in a changing marine environment: effects and risk

“…Besides accumulation zones of macrolitter, it is essential to have an improved understanding of microplastic (<5mm) formation mechanisms for estimating plastic particle sizes in the environment, and establish their potential for ingestion by marine organisms (Kooi and Koelmans, 2019). The ubiquity of microplastics in marine ecosystems requires further contextualization within a multi-stressor framework, as combined stressors can lead to synergistic effects (Catarino et al, 2022;Khan et al, 2022), and a broader vision of the plastic pollution impacts' magnitude is crucial for understanding and quantifying risks and effects in marine ecosystems. The goal of this research topic was to provide an overview of high-quality data collection (useful for risk assessment) and procedures, to report plastic litter and particles accumulation in the environment and biota, to investigate microplastic formation due to UV exposure, as well as to discuss potential interactions of plastic particles and climate change in future scenarios.Data infrastructures are vital for aggregating standardized information and providing insights on litter accumulation zones in the marine environment.…”