Date of Award

January 2019

Document Type


Degree Name

Master of Science (MS)


Earth System Science & Policy

First Advisor

Xiaodong Zhang


This study investigates the presence of microplastics in human consumable products using 33 samples; Fifteen tap water samples, nine bottled water and nine soft drink samples, collected and purchased in Grand Forks, ND.

Tap water analysis confirm all samples contain microplastics, majority of which were fibres and fragments with 48.6% and 41.8% abundance. The average concentration was 182 mpp/L (range 66 mpp/L – 472 mpp/L) with 2.5 µm – 3 mm size range. Bottled water and soft drinks were also contaminated with microplastics with an average of 101 mpp/L (range 49 mpp/L – 166 mpp/L) and particle size ranging from 5 µm – 1.4 mm. Fragments were most abundant with 51.7 % followed by fibres with 38.1 %. Soft drink samples were all contaminated with microplastics averaging 159 mpp/L (range 77 mpp/L – 256 mpp/L) with particles size > 3 µm – 1.2 mm. Morphologic analysis was done for particles > 100 µm thus, fragments were most abundant with 58. 7 % followed by fibres with 32.2 %.

Data suggests contamination was at least coming from surface run-off, waste water effluents and packaging or bottling itself. Analysis showed the prevalence of smaller particles less than 100 µm containing 84%, 92 % and 71 % of total microplastics analyzed in tap, bottled water and soft drinks, respectively. Our results give a substantial need for a well targeted research to better understand microplastic uptake, fate and health effects under relevant exposure scenarios.