Marine debris reach Antarctic seals: Fibers are the main ingested microplastic

JULIETA CEBUHAR; LUCAS S. RODRÍGUEZ PIRANI; A. LORENA PICONE; JAVIER NEGRETE; MAIRA PROIETTI; ROSANA M. ROMANO; CARLOS O. DELLA VÉDOVA; EDUARDO SECCHI; SILVINA BOTTA

Conferencia; MICRO 2022: Plastic Pollution from MACRO to nano; 2022

Contamination in the Antarctic ecosystem and biota has been reported since the 1990s,and concentrations of anthropogenic debris, including macro and microplastics, are increas-ing in this region. The interaction between fauna and microplastics has been described fromcrustaceans to penguins, but contamination in seals is still unknown. Here, we assessedmicroplastic contamination in three species of Antarctic seals from the Western AntarcticPeninsula (WAP) by analyzing 29 fecal samples of Lobodon carcinophaga (n=5), Leptoni-chotes weddellii (n=11) and Hydrurga leptonyx (n=13) collected at Cierva Cove. Feceswere sieved successively through four different sieve sizes (1, 0.5 mm, 500 and 300 µm) anddigested with KOH 10%. Samples were then evaluated with a binocular microscope andpotential microplastics were isolated. Procedural blanks (n=3) for each sample were usedthroughout the entire process. Micro-RAMAN and Micro-FTIR spectroscopies were usedto assess polymeric composition. Debris were present in all samples. The number of debrisper sample, per species was 12.4, 14 and 15.8 for leopard, Weddell and crabeater seals, re-spectively. The main particles found were fibers (n=237), fragments (n=130) and filaments(n=28), with sizes ranging from 0.02 to 40mm; black, blue and white were the dominantcolors, however other colors were also found. The RAMAN and Micro-FTIR spectra of 20%of samples up to now revealed black carbon, blue and green copper phthalocyanine pigments,semi-synthetic cellulose fibers and a polypropylene filament. This is the first evidence of an-thropogenic litter in scat samples of Antarctic seals, and the first evidence of black carbonin Antarctic biota. Despite the low number of ingested plastics, detection in 100% of thesamples of these top predators alerts to the potential impacts of these contaminants in thisremote region.