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Title: MICROPLASTIC POLLUTION IN THE TIJUANA ESTUARY BEACHESOF SOUTHERN CALIFORNIA
The Tijuana River Watershed encompasses 1750 square miles of territory in both Mexico and the United States, culminating at the National EstuarineResearch Reserve. While this area comprises one of the largest undisturbed wetlands in the state, it is one of the most polluted rivers in SouthernCalifornia, draining raw sewage and nonpoint source pollution. Despite extensive research, microplastic pollution along the beaches has not been explored. The objective of this study is to determine how the abundance and morphology of microplastic pollution in beach sediments vary with distance along the littoral cell from the Tijuana River outfall. Twenty samples were collected at 10 sites that span from the Tijuana River outfall to Mission Beach, San Diego. They are characterized as outfall sites, low-visitation beaches near the outfall, and high-visitation beaches further from the outfall. Solutions of 100ml sediment and 400ml hyper-saline solution were mixed and settled for 16 hours before being processed using a vacuum filtration system in a laminar fl ow hood. The microplastics (MP)were counted and classified using light microscopy. Laboratory practices to reduce laboratory contamination were employed and analytical blanks were run for every 3 samples. MPs ranged from 1 to 199/100ml sediment, of which approximately 91% were fibers. The greatest MP abundance occurred at the river outfall sites, but recovery rates were highly variable, and the analytical blanks ranged from 3-63/100ml sediment. The results oft his study suggest that microplastic distribution in sandy beach sediments is patchy but higher near the Tijuana River Outfall, and that future studies should report analytical blanks and employ methods to reduce contamination. Understanding the relationship between watersheds and microplastic distributions may inspire policy change on water quality protections in watersheds.  more » « less
Award ID(s):
1700920
PAR ID:
10487696
Author(s) / Creator(s):
;
Corporate Creator(s):
Editor(s):
no editor.
Publisher / Repository:
American Geophysical Union
Date Published:
Journal Name:
Ocean Sciences Meeting
Edition / Version:
1
Volume:
1
Issue:
1
Page Range / eLocation ID:
1
Subject(s) / Keyword(s):
microplastics tijuana estuary
Format(s):
Medium: X Size: 1 Other: 1
Size(s):
1
Location:
Honolulu, HI
Sponsoring Org:
National Science Foundation
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