Southcentral Alaska’s Water and Microplastics

Executive Summary

Plastic is ubiquitous– packaging, clothing, electronics, take out containers, and toys are just a few examples of items commonly made with plastic. Leo Baekeland patented the first fully synthetic plastic a little over a century ago and since then, humans have generated over 7 billion metric tonnes of plastic waste, and recycled less than 10% of it. Instead of moderating our plastic use, we’re actually increasing it. Globally, we produced 390.7 million metric tons of plastic in 2021, which is 40% more than was produced in 2011. 

Marine debris (much of it plastic) coats many of Alaska’s shores, and experts predict it will cost over $100 million to clean the pollution up, and more continues to wash up from the massive trash gyres in the Pacific. Marine entanglement from trash and fishing gear is common enough in Alaska that multiple stranding hotlines are set up.  On land, the Anchorage Chamber of Commerce coordinates an annual city clean up in May, and Anchorage Waterways Council hosts a simultaneous creek cleanup. Similar programs are set up in many other communities across the state, but litter is still a common sight. 

Steller sea lion with plastic packing band cutting into neck in Kenai Fjords National Park.Photo by ADF&G NOAA Fisheries | Public Domain

Litter and plastic debris are only a portion of the plastic waste in the environment. A recent study in the Atlantic Ocean found that only 1% of the plastic was big enough to be clearly visible with the naked eye and floating near the surface. A large share was micro or nano- pieces smaller than 5mm. When animal and plant based litter enters the environment, microbes including bacteria and fungi will break it down into basic chemical elements like carbon, potassium, nitrogen and other key minerals that in turn feed new life. However, plastic litter is composed of artificial chains of molecules in repeating patterns called polymers, and neither bacteria nor fungi have much success breaking them down into their basic components. Over time, friction and heat will break the plastic into smaller and smaller pieces, but they’ll still be plastic and unable to nourish new life for a very long time.  

Plastic doesn’t just persist in the environment, it threatens wildlife and public health. Larger pieces of plastic are laceration and starvation hazards. The smaller pieces have been found in our rain, air, and human bodies. Plastic additives include endocrine disrupting chemicals and attract toxins like DDT, PCBs, and heavy metals. Those toxic chemicals can bioaccumulate through the food chain, causing problems for animals and humans alike. 

As previously mentioned, microplastics enter our environment through a myriad of pathways and move through ocean and atmospheric currents, precipitation, and wind. Litter, illegal dumping, and landfill leakage are all obvious culprits. Microfibers are a prevalent type of microplastic and are introduced to the environment when we wash synthetic clothing. Wastewater treatment plants don’t fully filter these fibers out and approximately 40% end up in our waterways, oceans, and drinking water. The production of new plastic products uses pellets which are often lost and end up in waterways. Packaging and the process of creating products like bottled water can also cause microplastic contamination. 

Our waterways are a prime location to test for microplastics. Alaska’s watersheds are largely geographically isolated, with the exception of parts of Southeast which are downstream of Canada.  They provide drinking water for residents, habitat for fish and other aquatic life, and are both economically and culturally vital to the state. Southcentral Alaska is home to less than half a million people (the majority of the state’s population) and hosts a little under two million visitors annually. Microplastic testing in Southcentral Alaska provides additional insight into atmospheric redistribution of microplastics, key fishery exposure, and local information about drinking water. 

To better understand the scope of the microplastic problem in Alaska, Alaska Environment Research and Policy Center staff and volunteers sampled 39 water bodies in Southcentral Alaska. We found microplastics in 100% of our samples. 

Red dots indicate where samples were taken.Photo by Sean Kelly | Used by permission

Our project took samples from waterways between June and September 0f 2023 and tested them for four types of microplastic pollution: 

1. Fibers: primarily from clothing, textiles, and fishing line;
2. Film: primarily from bags and flexible plastic packaging;
3. Fragments: primarily from harder plastics or plastic feedstock;
4. Beads: primarily from facial scrubs and other cosmetic products. 

Microfibers were by far the most prevalent microplastic found in samples, and were found in 100% of samples. Micro fragments and films showed up in fewer locations, but were present in 20.5% and 33.3% respectively. Alaskans and tourists are almost certainly responsible for some of the microplastic pollution, but distribution patterns indicate some of the microplastic pollution is being swept in from other places as well. 

Moving left to right, top to bottom: fibers from Lake Wasilla, fiber wrapped around a film from Sand Lake, film from Tern Lake, fiber from tap water in the U-Med neighborhood of Anchorage, fibers (likely fishing line fragments) from Kenai Lake, fiber from the Little Susitna, fiber from University Lake, fibers from Kepler Lake.Photo by Dyani Chapman | TPIN

It’s clear that the scope of plastic pollution in Southcentral Alaska is extensive. In order to address the environmental and waste crisis being caused by our overreliance on plastics, our leaders at the federal, state, local, and corporate levels should implement policies that will address this problem.