GSA Annual Meeting in Denver, Colorado, USA - 2016

Paper No. 13-2
Presentation Time: 8:20 AM


SMITH, Jacqueline A.1, HODGE, James L.1, KURTZ, Bradley H.1 and GARVER, John I.2, (1)Physical & Biological Sciences, The College of Saint Rose, 432 Western Avenue, Albany, NY 12203, (2)Geology Department, Union College, 807 Union ST, Schenectady, NY 12308,

Microplastics are commonly defined as plastic particles less than 5 mm in diameter, whether deliberately manufactured to be that size or resulting from the fragmentation or erosion of larger pieces of plastic. Despite recent legislative bans, many personal care products such as facial scrubs still use tiny particles of plastic as abrasives. Plastic fibers, such as those released by laundering of polyester fleece, also make up part of the microplastic load potentially reaching waterways. Microplastic particles are a health hazard for aquatic organisms and an undesirable component of public water supplies. We are investigating the extent to which microplastic particles, both from personal care products and from other sources, are reaching the Mohawk River in upstate New York. The Mohawk River is the main tributary of the Hudson River, coinciding with the Erie Canal for stretches downriver from Rome, NY (43.20256° N, 75.47824° W), and serves as the water supply for several municipalities (e.g., Latham, NY). We used a manta trawl deployed from a rigid inflatable boat to collect 60 samples of planktonic material along the 112-mile section of the Mohawk River and/or Erie Canal between Rome, NY, and the Crescent Dam in Cohoes, NY (42.80685° N, 73.72276° W). Each trawl lasted for ~1 mile. We used an Ekman grab sampler to collect 64 samples of channel sediment along the same section of the Mohawk River and/or Erie Canal. Sample processing for planktonic samples includes sieving and wet peroxide oxidation to remove organic material. Sample processing for sediment grab samples includes drying, sieving, density separation, and wet peroxide oxidation. Anthropogenic particles that contain dye are easiest to spot under a microscope. Laboratory analyses are currently underway; preliminary results indicate that the majority of the planktonic samples include dyed particles. Raman spectroscopy provides definitive identification of plastics and other anthropogenic materials, including paint. We used Raman spectroscopy to match fragments of paint found in planktonic samples previously collected from the near-shore Mohawk and Hudson Rivers to the type of paint used on some of the locks on the Erie Canal.