Quantitative Analysis of Microplastics on Texas Beaches

Abstract

Marine debris and microplastics have been found in all marine environments from the open ocean, to pelagic waters and beach sediments. A recently published two-year survey of marine debris spanning the Gulf of Mexico (GofM) from North Padre Island, Texas to Santa Rosa, Florida found that marine debris accumulation rates were ten times greater in Texas than similar coastlines of the north central GofM. The goal of this study was to determine if there were discernible differences in the abundance or quality of plastic pollution on Texas state beaches and investigate potential causes. Collections took place at three beach sites (Galveston Island, Mustang Island and Sea Rim) and during the months of summer (June-August), fall, (September to November(of 2019, and winter (January to March) 2020. (TPWD Pe No: 2019-R4-0l). At each beach, a 50X1-meter transect was laid out on the high tide line, which was established visually by the wrack line and water marks. A total of 4179 microplastics, categorized as 4214 plastics, 155 nurdles, and 27 fibers were collected at all three sample sites from June 2019 to March 2020. The most common colors observed were blue, green, and white. During summer and fall 2019 the beach with the greatest microplastic pollution was Galveston Island State Park and during winter 2020 the site with the greatest microplastic pollution was Mustang Island State Park The presence of microplastics on state park beaches may indicate that microplastic pollution occurs with sandy beach meiofauna and macrofauna. This study will result in the identification of trends in dispersal and seasonality of microplastics on the Texas coast.