Microplastic–toxic chemical interaction: a review study on quantified levels, mechanism and implication

Abstract

Current problem facing researchers globally is microplastics as well as toxic chemical pollution of the ecosystem. Microplastics carry toxic chemicals in the ecosystem serving as a vector for transport. In this study, a review of the literature has been conducted with the following objectives: (1) to summarize the concentrations of toxic chemicals such heavy metals and hydrophobic organic contaminants sorped on microplastics; (2) to evaluate their spatial distribution regarding adsorbed contaminant; (3) to discuss plausible mechanism by which microplastics adsorp or desorp toxic chemicals in the environment; (4) to discuss implications of their occurrence in air, water and soil media; and (5) to discuss the impact of ingested microplastics to human health. Microplastics are ubiquitous environmental contaminant. Concentrations of sorped toxic chemical varied by location which represents a local problem; industrialized areas (especially areas experiencing crude oil-related activities or have history of crude oil pollution) have higher concentrations than less industrialized areas. Ingestion of microplastics has been demonstrated in a range of marine and soil organisms as well as edible plants, thus possibly contaminating the base of the food web. Potential health effect to human is by particle localization, chemical toxicity and microbial toxins. We conclude by highlighting the gap in knowledge and suggesting key future areas of research for scientists and policymakers.

Microplastic Contamination in Freshwater Environments: A Review, Focusing on Interactions with Sediments and Benthic Organisms

“…For example, Wang and Wang [99] observed a higher adsorption rate of PAHs on different polymer pellets than in natural sediments. Nonetheless, the equilibria between the adsorbed and dissolved phase need to be further investigated to understand the final sink of POPs and consequent ecotoxicological effects [105,106].…”

“…From an ecotoxicological point of view, MPs have been detected in different aquatic organisms since they can be ingested, and accumulation along the food web has been observed in different settings [86,90,144]. Moreover, plastic particles can act as vectors of toxic chemicals to the biota [106,178]. Nonetheless, the toxic effects of MPs, especially regarding adsorption-desorption equilibria in environmental conditions, need to be investigated further, since the vector effect of MPs for pollutants still presents contradictory results [124,125].…”

A Detailed Review Study on Potential Effects of Microplastics and Additives of Concern on Human Health

“…Just like many other hydrophobic contaminants, evidence of attachment of PBDEs onto microplastics from marine environment has been highlighted in recent years [42,141,142], and the assimilation of these pollutants by organisms that ingest microplastics is highly probable [141,143,144]. Different levels of PBDE concentrations on microplastic samples have been observed based on polymer type and local anthropogenic activities.…”

Microplastics from degradation of tires in sewer networks of the city of Riobamba, Ecuador

“…Overall, most (60%) of the study points showed positive relating to degradation of tires from road frictions. Other likely source(s) could be from atmospheric deposition [15], which may account for the other 40% in PC2.…”

“…The friction between the asphalt in contact with the tires of the cars generates the detachment of small residues [14]. Adding of physical factors such as wind [15] and water tend to move into gutters and mix with domestic and industrial wastewater and in the end may appear in the various sewer systems, there is direct contact of these waters with the biological environment becoming a major problem for the habitants of the city [16]. Therefore, the aim is to determine the percentage of source MPs from friction-degraded tires in sewer systems with the city of Riobamba as a case study.…”