S2.3: Snapshot of the Microplastics Research Proposal

(Reference 6)

The Presence of Microplastics in the City of Phoenix Public Drinking Water

Over the past decade several research experiments have indicated that society is now in the “Age of Plastic” and traces of plastic can be found virtually everywhere. Even when plastic seems to be broken down, not visible to the naked eye, it is still present on the microscopic level and polluting air, surface water, oceans, sediments, and marine life including types of seafood (Rochman et. al. 2015). Microplastics are also found in personal care products and machine-washed clothing (Wright and Kelly 2017). However, the question remains as to whether microplastics have polluted public drinking water. It appears as though only one public observational experiment surveying tap water has ever been performed. Research conducted by Kosuth et. al. (2017) collected 150 water samples from six regions on five continents, including parts of the US and found that 83% of tap water around the world contained microplastics, and of the samples taken in the United States, 94% of water contained microplastics. The researchers of the experiment expressed the need to further test geographical regions, and include more information about water sources and ground filtration methods prior to human use to better understand potential pathways of contamination. Phoenix is the 5th largest city in the country and the eighth fastest growing city in the United States (USA Today 2018). It is imperative to test Phoenix public drinking water for a number of reasons: Phoenix is one of the fastest growing cities; research on microplastics in tap water for the City of Phoenix is not publicly available and possibly has not be researched to date; and to contribute data to the emerging field of microplastics and its effect on human health.

Research questions

Are microscopic plastic particles and fibers present in public drinking water throughout the
City of Phoenix.

Are microscopic plastic particles and fibers present in filtered water and store-bought bottled water?

Hypothesis

Hypothesis 1: Samples of drinking water taken in the Phoenix Metropolitan Area will be positive
for microplastics.

Null Hypothesis: Samples of drinking water taken in the Phoenix Metropolitan Area will be
negative for microplastics.

Independent Variables: Location and type of  drinking water sample

Dependent Variable:  The amount of microplastics found in water sample

Control Variable: Vacuum Filter, Deionized Water (500mL), 2 mL Rose Bengal Dye,
Volume of Water Sample (500mL), water sample collection method, vacuum filter paper
(1.75 µm), laminar airflow cabinet, and Microscope.

Key Words:

Microplastics: Microplastics are small plastic pieces less than five millimeters long
which can be harmful (adapted from the NOAA)

Drinking Water: tap water which comes from public sources, residential homes, filtration
systems and bottled water

References

1.Comen, E. (2018, January 15). The fastest growing (and shrinking) states: A closer look. USA

Today. Retrieved February 08, 2018, from https://www.usatoday.com/story/money/economy/
2018/01/15/fastest-growing-and-shrinking-states-closer-look/1019429001/

2. Gerd Liebezeit & Elisabeth Liebezeit (2014) Synthetic particles as contaminants in German

beers, Food Additives & Contaminants: Part A, 31:9, 1574-1578, DOI: 10.1080/19440049.2014.945099

3.Kosuth, M., Wattenberg, E., Mason, S., Tyree, C., & Morrison, D. (2017, May 16). Synthetic

Polymer Contamination in Global Drinking Water (Rep.). Retrieved February 01, 2018, from Orb Media website:
https://orbmedia.org/stories/Invisibles_final_report

4.National Ocean Service. 2017. What are microplastics? National Oceanic and Atmospheric

Administration. United States Department of Commerce. https://oceanservice.noaa.gov/facts/microplastics.html

5.Rochman, Chelsea M., Tahir, Akbar, Williams,Susan L., Baxa Dolores V., Lam,Rosalyn,

Miller,Jeffrey T., Teh, Foo-Ching , Werorilangi,Shinta, Swee, Teh. Anthropogenic debris in seafood:
Plastic debris and fibers from textiles in fish and bivalves sold for human consumption. Sci Rep. 2015; 5: 14340.
Published online 2015 Sep 24. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4585829/

6. http://www.phoenixasap.com/gfx/phoenix-villages.png