Propylene Glycol

Propylene glycol is a small, carbon-based molecule that is in the alcohol family, along with the more familiar compounds ethanol (drinking alcohol) and isopropyl (rubbing alcohol). Propylene glycol is a common ingredient in pharmaceuticals, cosmetics and deodorant sticks. It also finds application as a de-icing compound and antifreeze.

Propylene Glycol is an organic contaminate in the same family chemicals like PCBs, DDT, chlordane, and dioxins, which are listed by the EPA as probable human carcinogens (cancer causing agents) and that tend to remain in the environment for an extremely long time. In some waterbodies, these substances have accumulated in sediment and pose a health threat to those that consume fish or shellfish.

Propylene glycol is known to exert high levels of biochemical oxygen demand (BOD) during degradation in surface waters. This process can adversely affect aquatic life by consuming oxygen needed by aquatic organisms for survival.

Problematically unhealthy levels of organic contaminates can be below current detection levels. Detection of these substances is generally made either by analyzing fish tissue levels and/or by use of sediment screening values provided by the EPA. Since organic contaminants can bioaccumulate in fish, it is important to make sure catfish and other species consumed by people are safe to eat. Children and pregnant or nursing women are the most sensitive sub- population.

Typically, propylene glycol finds its way to our water via production and processing facility wastewater, from spills, or from de-icing fluid carried by stormwater runoff.

How You Can help

Are you a member of a group or organization in your community that would be interested in adopting this waterway? Contact the Cumberland River Compact if you’re interested in learning more about stream adoption.

Deicing can be extremely detrimental to aquatic ecosystems. Make use of non-toxic options where possible. Encourage those responsible for significant deicing activity in your community to consider non-toxic or less toxic options.

Resources include:
1) How to Reduce the Environmental Impact of Deicing Roads - Pacific Northwest Pollution Prevention Resource Center
2) Explore a variety of eco-friendly deicing options in EPA’s Safer Choice list . - EPA
3) Managing Highway Deicing to Prevent Contamination of Drinking Water. - EPA

If you live or work next to a waterway, leave a 35′ to 100′ no mow zone on its banks. Allow natural and native plant growth in this buffer area or plant native trees, bushes, and groundcover. This vegetation can filter pollutants before they reach your waterway and provide other water quality benefits that far exceed those of a mowed lawn. Native plants and grasses require less watering and fertilizer and also provide important habitat for native species of wildlife.

Resources include:
1) Free trees for Tennesseans during TEC's annual statewide 100K Tree Day - TN Environmental Council
2) Purchase Native Wildflower/Grass Alternatives to Mowed Grass - Roundstone Native Seed and/or Seedland
3) Tennessee Aquatic Stream Clean Up and Riparian Tree Grant (Scroll to bottom of linked page for more info) - TN Wildlife Resources Agency
4) General Guidelines for Volunteer Based Riparian Buffer Plantings - TN Environmental Council
5) Improving Stream Channels With Live Staking - UT Extension
6) Tennessee Urban Riparian Buffer Handbook - TN Dept. of Agriculture
7) Landscaping with Native Plants in West, Middle, and East TN - TN Wildlife Resources Agency
8) Native Plants for TN - UT Extension
9) Forest Stewardship Program and Landowner Services - KY Division of Forestry
10) Plant Availability Guide - KY Department of Agriculture
11) State Nurseries and Tree Seedlings - KY Division of Forestry

Rain gardens can filter and infiltrate stormwater that flows across your yard.

Resources include:
1) Rain Gardens - A Resource Guide - Cumberland River Compact and Metro Nashville
2) TN Native Rain Garden Plants - UT Extension
3) Rain Gardens for Tennessee - UT Extension
4) Rain Gardens Educator's Toolkit, Rain Gardens for Tennessee Site Summary, and Rain Garden Facts and Tips - UT Extension
5) Rain Garden How-to Brochure - Harpeth River Watershed Association
6) Rain Garden Guide for Middle Tennesseans by Patty Ghertner
7) Start-to-Finish Rain Garden Workbook - Harpeth River Watershed Association
8) Rain Garden Workshop Guide - TN Environmental Council
9) Landscaping with Native Plants in West, Middle, and East TN - TN Wildlife Resources Agency
10) Native Plants for TN - UT Extension
11) Plant Availability Guide - KY Department of Agriculture

Impervious or impermeable surfaces, like pavement, contribute significantly to polluted stormwater runoff and alter stream flow habitat. If you've got excess pavement you'd like removed, consider a de-paving project with the Compact. Elsewhere, ensure that your downspouts drain to vegetation, gravel, or rainbarrels, rather than impervious surfaces. If you constructing or repairing your driveway, pervious pavement allows stormwater to infiltrate and filter through the ground. If you can’t do the whole drive, consider making only the portion closest to the street pervious.

Resources include:
1) De-paving Work - Cumberland River Compact (Call 615-837-1151)
2) Rain Barrel Sales - Cumberland River Compact
3) Rain Barrels Make Good Sense - UT Extension

Participate in community planning efforts and advocate for relevant measures that improve or protect water quality. Write to your elected official and let them know this is concern or invite them to speak about the impairment with your home-owners association. When elections come up, vote for candidates who will address the problem and hold them accountable to their promises. Support local watershed / environmental associations.

Resources include:
1) Advocacy Toolkit - TN Environmental Council
2) Find Your Legislators - Federal Legislators; State Legislators (KY/TN); Local Legislators (KY/TN)

Do your neighbors, family, or roommates know about the problem? Now that you know how to be an effective steward, enlist the help of others in your neighborhood. Share iCreek or resources within it with your neighbors and encourage them to join the effort to protect your creek.