Offshore surface waters of Antarctica are free of microplastics, as revealed by a circum-Antarctic study

In 2018, during a circumnavigation of Antarctica below 62° S by the sailing boat Katharsis II, the presence of plastics was investigated with surface sampling nets at ten evenly spaced locations (every 36° of longitude). Although fibres that appeared to be plastic (particles up to 2 cm) were found in numbers ranging from 1 particle (0.002 particles per m3) to 171 particles (1.366 particles per m3) per station, a Fourier-transform infrared spectroscopy (FT-IR) analysis indicated that these particles were not composed of plastic. The fibres which superficially reminded plastic were composed of silica and are of biological origin most likely generated by phytoplankton (diatoms). Therefore, the offshore Antarctic locations were proven to be free of floating microplastics.