Microplastic Density and Shore Visitor Abundance at Two Long Island Beaches

Abstract

Degradation of coastal ecosystems due to plastic pollution, particularly on the micro scale, is a topic of growing concern as microplastics are found to be detrimental to wildlife, and carriers of toxins and pollutants. The density and lengths of plastics are reported from two Long Island south shore beaches, one with high patron usage (Jones Beach) and the other with lower patron usage (Lighthouse Beach, Fire Island). At each site, five sand samples of ca. 425 cm3 collected from the wrack line and five were collected from the backshore (50 m upshore from the wrack line). Plastics were density-separated using a concentrated saltwater solution (1.7 g mL-1), and the supernatant was filtered. After drying, each filter was examined at 25X magnification and the counts and lengths (mm) were scaled up to microplastic quantities and lengths per kg of sand. The results of this study determined there were no significant differences between the two beaches, or between wrackine and backshore locations in either microplastic counts or lengths. There also was no significant relationship between plastic particles <1.0mm and plastic particles ? 1.0mm in samples collected. This data did not support a relationship between microplastic density or size and patron usage.