Plastic Interactions with Pollutants and Consequences to Aquatic Ecosystems: What We Know and What We Do Not Know

Abstract

Plastics are a group of synthetic materials made of organic polymers and some additives with special characteristics. Plastics have become part of our daily life due to their many applications and uses. However, inappropriately managed plastic waste has raised concern regarding their ecotoxicological and human health risks in the long term. Due to the non-biodegradable nature of plastics, their waste may take several thousands of years to partially degrade in natural environments. Plastic fragments/particles can be very minute in size and are mistaken easily for prey or food by aquatic organisms (e.g., invertebrates, fishes). The surface properties of plastic particles, including large surface area, functional groups, surface topography, point zero charge, influence the sorption of various contaminants, including heavy metals, oil spills, PAHs, PCBs and DDT. Despite the fact that the number of studies on the biological effects of plastic particles on biota and humans has been increasing in recent years, studies on mixtures of plastics and other chemical contaminants in the aquatic environment are still limited. This review aims to gather information about the main characteristics of plastic particles that allow different types of contaminants to adsorb on their surfaces, the consequences of this adsorption, and the interactions of plastic particles with aquatic biota. Additionally, some missing links and potential solutions are presented to boost more research on this topic and achieve a holistic view on the effects of micro- and nanoplastics to biological systems in aquatic environments. It is urgent to implement measures to deal with plastic pollution that include improving waste management, monitoring key plastic particles, their hotspots, and developing their assessment techniques, using alternative products, determining concentrations of micro- and nanoplastics and the contaminants in freshwater and marine food-species consumed by humans, applying clean-up and remediation strategies, and biodegradation strategies.

Microplastics influence the functional responses of a tropical estuarine calanoid Pseudodiaptomus annandalei

“…Copepods can ingest plastics by either selective grazing or by indiscriminately ingesting particles with natural prey (Traboni et al, 2023). Copepods can also actively refuse MPs or passively reduce MP intake by physical impacts/interference or chemical toxicity associated with plastics (leachates or sorbed pollutants) (Caśsio et al, 2022). Similarly, the presence of plastics in the environment, along with natural prey, may obstruct predatorprey interactions, leading to a reduced prey ingestion rate (Turner and Tester, 1989).…”

Distribution and Fate of Polyethylene Microplastics Released by a Portable Toilet Manufacturer into a Freshwater Wetland and Lake

“…The state government cited the company for violations of the Clean Water Act, and it was directed to clean up the microplastic pollution and institute provisions to "insure containment of plastic materials" [36]. Since microplastics embed in sediment [37], adsorb to plants [3] and other living tissue [38], and readily move through aquatic environments [39], remediation of this pollution is a difficult endeavor. Efforts by the company and the city to remediate the pollution have included the placement of booms (also made of plastic and disintegrating over time), the suctioning/removal of contaminated water, and the placement of tarps along the property fence line.…”

A domesticated photoautotrophic microbial community as a biofilm model system for analyzing the influence of plastic surfaces on invertebrate grazers in limnic environments

“…Grazing may lead to abrasion of micro- or nanoplastic particles that may be toxic for the forager; additionally, microorganisms in the biofilms can mobilize plastic additives with toxic effects ( Fauser et al, 2022 ; Ockenden et al, 2022 ). As plastic is known to adsorb chemicals from the water such toxic effects may also arise from exogenous compounds ( Yu et al, 2021 ; Cássio et al, 2022 ). Additives or adsorbed chemicals may also influence the food quality of biofilms for grazers.…”