MICROPLASTICS IN DUNE SANDS FROM OUTER CAPE COD, MASSACHUSETTS
Filamentous microplastic fibers were ubiquitous in sediments from the following size fractions: 3 phi (.125 mm) and smaller, 2.5 phi (.178 mm), and 2 phi (.250 mm). Microplastic filaments in the smaller size fractions formed tumbleweeds as large as 5 mm made up of tangled microplastic fibers. These formed during operation of the sieve shaker. In contrast, even after shaking, microplastic fibers were dispersed as individual strands between grains in the 2 phi fraction. Microplastic filaments appearing as tumbleweeds and single strands were observed in surface samples as much as 1 km landward of the beach on the leeward side of dunes suggesting that aeolian transport is a significant factor in the introduction of microplastics into the terrestrial realm.
Future work entails examination of sediment samples taken along transects perpendicular to the coast as well evaluation of sediments from previously sampled sites taken in the autumn after tourist season, during the winter storm season, and in the spring after storms have subsided in order to assess the effects of seasonal variations in conditions such as wind speed in the abundance of these microplastics.