Polyethylene microplastics do not increase bioaccumulation or toxicity of nonylphenol and 4-MBC to marine zooplankton

• Published in: The Science of the total environment 2019-11, Vol.692, p.1-9
• Main Authors: Beiras, Ricardo, Muniategui-Lorenzo, Soledad, Rodil, Rosario, Tato, Tania, Montes, Rosa, López-Ibáñez, Sara, Concha-Graña, Estefanía, Campoy-López, Pedro, Salgueiro-González, Noelia, Quintana, José Benito
• Format: Article
• Language: English
• Subjects: 4-MBC; Animals; Aquatic Organisms; Bioaccumulation; Camphor - analogs & derivatives; Camphor - metabolism; Camphor - toxicity; Copepoda - drug effects; Larva - drug effects; Larva - growth & development; Microplastics - analysis; Nonylphenol; Paracentrotus - drug effects; Paracentrotus - growth & development; Phenols - metabolism; Phenols - toxicity; Plastics; Polyethylene - analysis; Toxicity bioassays; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - toxicity; Zooplankton - drug effects
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2019.07.106

Global production of synthetic polymers, led by polyethylene (PE), rose steadily in the last decades, and marine ecosystems are considered as a global sink. Although PE is not biodegradable, in coastal areas it fragments into microplastics (MP) readily taken up by biota, and have been postulated as vectors of hydrophobic chemicals to marine organisms. We have tested this hypothesis using two organisms representative of the marine plankton, the holoplanktonic copepod Acartia clausi, and the meroplanktonic larva of the Paracentrotus lividus sea-urchin, and two model chemicals with similar hydrophobic properties, the 4-n-Nonylphenol and the 4-Methylbenzylidene-camphor used as plastic additive and UV filter in cosmetics. Both test species actively ingested the MP particles. However, the presence of MP never increased the bioaccumulation of neither model chemicals, nor their toxicity to the exposed organisms. Bioaccumulation was a linear function of waterborne chemical disregarding the level of MP. Toxicity, assessed by the threshold (EC10) and median (EC50) effect levels, was either independent of the level of MP or even in some instances significantly decreased in the presence of MPs. These consistent results challenge the assumption that MP act as vectors of hydrophobic chemicals to planktonic marine organisms. [Display omitted] •Sea-urchin pluteus and copepod nauplius larvae actively ingest microplastic particles.•Microplastics did not increase accumulation of organic chemicals in sea-urchin larvae.•Microplastics did not increase the toxicity or 4-n-NP or 4-MBC to zooplankton.•PE microplastics do not act as vectors of hydrophobic organics to zooplankton.