A comparative study on the potential effects of plastic contamination using Iso-Seq

Abstract

Despite many field studies of microplastic contamination in marine environments, fewer studies have clarified the adverse effects derived from microplastic contamination in marine resident species. This is the first report to evaluate the toxic effects of environmental in situ plastic litter exposure on wharf roaches (Ligia exotica). L. exotica occupies an important ecological position as a detritus consumer. An experimental survey was conducted from May–June 2019 in two South Korean nearshore sites: Maemul-do [microplastic-contaminated] and Nae-do [microplastic-uncontaminated]. The average microplastic abundance (>20 μm) in L. exotica was higher at Maemul-do (50.56 ± 93.99 particles/individual) Nae-do (1.00 ± 1.00 particles/individual). The composition of microplastics was dominated by expanded polystyrene(EPS) in L. exotica from Maemul-do (93.3%). Genome-wide transcriptome profiling (Iso-Seq) revealed significantly altered expression of genes associated with fatty acid metabolic processes, the innate-immune response-activating system, and vesicle cytoskeletal trafficking in L. exotica from Maemul-do. Our findings highlight the importance of understanding the toxic effects of translocated microplastics in resident species to better manage microplastic pollution using bioindicators.