STC’s air quality monitor set up in its environmental enclosure at 11th and Broadway.

STC’s study is looking specifically at what is called particulate matter (PM) 2.5. Particulate matter is a term used for airborne particles and liquid droplets. 2.5 refers to the size of the particle. The particles we are looking at are 2.5 microns in diameter or smaller. The graphic to the right gives a clear illustration of how truly small these particles are. Particles 10 microns and smaller have been shown to have negative health effects; however, those that are 2.5 or less are of the greatest health concern. The reason these very small particles can be so dangerous is that they can be inhaled, get deep into our respiratory tract and even enter the blood stream.

Graphic borrowed from EPA website (https://www.epa.gov/sites/production/files/2014-05/documents/huff-particle.pdf)

There are many sources of Particulate matter pollution including wood-burning stoves, forest fires, industry, cars and buses, and diesel engines. During our tourist season Skagway has a huge influx of buses and traffic constantly moving through town, the train heading up the pass many times a day, and diesel exhaust from cruise ships in port. Having data about how these activities are impacting Skagway’s air will give the Skagway community the ability to make better informed decisions about air pollution and hopefully help us keep our air as beautifully clean as it is this season.

You may have seen these set up around town this spring and summer and wondered what they are…

These are STC’s air quality monitors. STC has three TSI DustTrak monitors that we have been deploying in three locations in Skagway since early April. One near the small boat harbor, one near the STC Tribal Community Center, and one at the north end of town.

STC’s environmental department is using these monitors to look at particulate matter (PM) in Skagway’s air. Our original study was designed to observe the impact of cruise ships and related tourist traffic on the air quality of Skagway during the 2020 season. This turned out to not be possible this year due to the absence of tourism. However, the unique circumstances of 2020 have left us with a valuable opportunity to see what Skagway’s air looks like without the influence of the cruise ship industry. We will collect data this season and then repeat this study next year as cruise ships return. This will allow us to compare results and get much clearer picture of how much or little tourism is affecting the air in our community.

Graphic borrowed from EPA website (https://www.epa.gov/pm-pollution/particulate-matter-pm-basics)

If there is particulate matter in the air, a person is exposed every time they breath in. Particulate matter smaller than 2.5 microns can include acids, organic chemicals, metals, dust, and allergens. While symptoms of exposure can be just temporary coughing, shortness of breath or eye irritation, there are many serious health concerns associated with PM 2.5. Lung disease, heart disease, cancer and asthma have all been associated with exposure to particulate pollution. Efforts and regulations have been put in place nationally to reduce particulate matter pollution in order to keep air clean and people healthy. Understanding the sources of particulate matter both on a large scale and at a local level can be very valuable in this effort.

Photograph from Alaska Department of Environmental Conservation (file:///C:/Users/User/Downloads/cpvec-2015report%20(2).pdf)