Influence of wastewater treatment plants and water input sources on size, shape, and polymer distributions of microplastics in St. Andrew Bay, Florida, USA

Mar Pollut Bull. 2023 Feb:187:114552. doi: 10.1016/j.marpolbul.2022.114552. Epub 2023 Jan 7.

Abstract

Microplastic (MP) pollution is an ongoing problem in coastal systems, where wastewater treatment plants (WWTPs) deposit particles daily. This study examined MP characteristics at WWTP outflow and control sites in St. Andrew Bay in Northwestern Florida, USA. WWTP sites contained mostly polypropylene fragments (180.1 μm avg. size), while reference sites contained polypropylene fragments, and polyethylene and polyester fibers (315.3 μm avg. size). MP sizes were strongly linked to distance from the nearest WWTP, while shape and polymer compositions were more closely related to dissolved oxygen concentrations and distance to the nearest water input source. The prevalence of polypropylene fragments at WWTP sites suggests that extreme weather events during the study flushed land-based debris into the system, where it was buried in the sediments. Increased abundances of polyester and polyethylene terephthalate in the winter at WWTP sites are indicative of the role that laundering synthetic textiles plays in coastal MP pollution.

Keywords: Coast; Conservation management; Pollution; Polypropylene fragments; Sediment; Wastewater.

MeSH terms

  • Bays
  • Environmental Monitoring
  • Florida
  • Microplastics
  • Plastics
  • Polyethylene Terephthalates
  • Polymers
  • Polypropylenes
  • Water
  • Water Pollutants, Chemical* / analysis
  • Water Purification*

Substances

  • Microplastics
  • Plastics
  • Polymers
  • Polypropylenes
  • Water
  • Water Pollutants, Chemical
  • Polyethylene Terephthalates