Microplastics in Antarctic penguins and seals in Admiralty Bay, King George Island, Antarctica

The occurrence of microplastics in top predators was evaluated during summer 2020 along Punta Crepín through the analysis of fresh scats of seals and penguins. We collected 37 scats – 23 from penguins, likely Pygoscelis papua (the most frequent in the area), and 14 from seals (3 Mirounga leonina and 11 likely Leptonychotes weddellii, the most frequent). Scats were digested with 20 percent KOH and put at 60°C for 5 days. The solution was vacuum filtered through 4 μm pore size filters. Suspected microplastics were analyzed by micro Fourier Transformed Infrared Spectroscopy (μFTIR). About penguins, 56.5 percent contained suspected particles, mainly fibers (90.5 percent), predominantly blue color (81.0 percent). Among these particles 77.3 percent were cellulose, 9.1% were PET and acrylic resin + kaolin, and 4.5 percent were polyacrylic polymer according the μFTIR analysis. Concerning seals, samples from Mirounga leonina did not present MPs while in the scats of likely L. weddellii, six had fibers (91.3 percent) of colors blue (56.5 percent) and red (30.4 percent). Overall the μFTIR for suspected particles in seal scats revealed 81.8 percent were cellulose and the rest were PET. Our findings indicated the presence of PET and acrylic resins, as well as cellulose particles, in low incidence, probably derived from the consumption of contaminated prey like Antarctic krill.