Residual additives in marine microplastics and their risk assessment – A critical review. (April 2022)

• Record Type: Journal Article
• Authors: Fauser, Patrik; Vorkamp, Katrin; Strand, Jakob
• Is Part Of: Marine pollution bulletin. Volume 177(2022)
• Publication Date: 2022-04
• Subjects: Bioavailability -- Chemicals -- Leaching -- Monomer residuals -- Degradation products -- Weathering; Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2022.113467
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: This review summarizes the current state of knowledge regarding the risk assessment of plastic-associated residual additives, i.e. residual monomers, degradation products and additives, in the marine environment, also considering effects of weathering and bioavailability. Experimental studies have found a number of organic and metal additive compounds in leachates from plastics, and the analysis of weathered plastic particles, such as polyethylene, polypropylene and polystyrene particles sampled on beaches and shorelines, has identified residual additives, such as flame retardants, plasticizers, UV stabilizers and antioxidants. While the transfer of e.g. PBDEs to organisms upon ingestion has been demonstrated, studies on uptake and bioaccumulation of plastic-associated chemicals are inconclusive. Studies on hazard and risk assessments are few, and focus on monomers and/or a limited number of high concentration additives, such as phthalates and flame retardants. The risk assessment results vary between low, moderate and high risks of specific additives, and are not necessarily consistent for the same compound. Given the large number of chemicals potentially introduced into the marine environment with plastic particles and the challenges associated with the correct quantification of exposure concentrations and toxicity thresholds, the question arises whether new risk assessment concepts may be needed. Highlights: Few risk assessments of additive residuals in MP in the marine environment exist. Results vary from low to high risk, and are not consistent for the same additive. Significant amounts of residuals are found after weathering compared to new polymer. Distinguishing additives in production from sea uptake is not straightforward. Risk assessment of MP should also consist of a risk component from plastic particle.