Science Corner: One Person’s Trash Could Be Another Person’s Earthship

You’ve probably noticed that the world is a bit of a mess. Every day it seems that there is some new problem that requires our attention and/or provides some new topic for people to argue about discuss and debate. Some of the issues that spawn arguments discussions are trivial matters like whether pineapple belongs on pizza (yes, it absolutely does). Other topics, like global climate change, the impact people are having on the planet, and our responsibility as Christians to care for the Earth, are much more serious. The opinions on this second matter are wide ranging, and it is not my intention to argue about debate the issue in this space and time. Rather, I hope we agree that, as people who have been commanded to love our neighbors, we could do a better job caring for the living space, (i.e., the Earth) we share by being conscious of the mess and cleaning up after ourselves.

This should be, as my daughters put it, easy-peasy, right? We can recycle paper, aluminum, and glass. We can repurpose plastic containers for storing our leftovers and random odds and ends. We can avoid “fast-fashion” and make clothes we no longer want available for someone else to wear. We can make an effort to repair things that are broken instead of just replacing them. And there are other relatively simple things we can do to control the chaos created by the stuff we use in our daily lives. Unfortunately, not all messes are so easy-peasy to deal with, and they require more thought and creativity to manage. Messes, for example, like used tires.

Tires are one of those things that is easy to take for granted. I suspect that most of us don’t give them much thought except when the “low tire pressure” light comes on in our cars. However, used tires are a significant global mess, and should be given more consideration. According to current estimates, 4 billion end-of-life tires (i.e., tires that can no longer be used on vehicles) are in landfill tire mountains, and tire graveyards worldwide, and an additional 1 billion are added each year. The largest tire graveyards are located in Kuwait and India, but there are also significant stockpiles located in other places, including in the United States.

I hope it’s not surprising to you that these large tire piles are a significant environmental and health hazard. On the extreme side of things, if a pile catches on fire, it produces toxic smoke that includes cyanide, carbon monoxide, and sulfur dioxide. A more common, but also serious, problem is that tire piles collect water and create an insulated breeding grounds for mosquitoes that act as vectors for malaria, and viruses that cause illnesses like yellow fever, Dengue, West Nile virus, Chikungunya, and Zika. One mosquito that takes full advantage of our waste tires is the Asian tiger mosquito, Aedes albopictus. This mosquito is considered one of the most invasive species on Earth. It originated in tropical Southeast Asia, but it now found worldwide, in part, because of our used tire problem. They arrived in the United States around 1985 in a shipment of used tires from Japan. They are now found in 40 states, and their range will likely continue to expand partly through natural population dispersal but also through continued movement and storage of tires. In fact, a recent study showed that snow covered tires provide insulated microhabitats that allow A. albopictus to expand their range into colder, more northern climates, than initially predicted.

So, what can be done about this tire mess? A significant portion of used tires are already being repurposed, but some of the alternatives seem wiser than others. For example, a large portion of used tires are being burned for fuel, which we already seen creates another type of mess to clean up. Wiser solutions include shredding tires and using them as filler in insulation or asphalt. Some tires are shredded and used in the construction of roadbeds, retaining walls, or other barriers. Some others are ground up and used to make padded surfaces on playgrounds. Some are being used by a group in India make inexpensive, durable shoes. It seems to me that it would be worthwhile look for more creative ideas, like these, that use tires without creating toxic air pollution.

One of my personal favorite ideas for reusing old tires is in the construction of Earthship homes. These are highly efficient, “green” homes made from earth-packed tires and other repurposed materials like aluminum cans and beer bottles. The original Earthships were conceptualized by Michael Reynolds with the goal of creating a self-contained, sustainable home that provides its own energy via solar and wind power; clean water via water harvesting and storage, and food via in-home greenhouses. The first Earthships were built in New Mexico, and can now be found worldwide in Africa, Australia, Europe, South America, and Canada.

Could widespread adoption of Earthship-style construction be the solution to the tire mess? Maybe. Each three-bedroom Earthship uses 800-1000 tires, that are insulated with packed earth to prevent them from burning, among other things. In addition, they provide solutions for additional environment-related problems including reliance on fossil fuels. However, many communities have strict building codes that currently limit locations where Earthships are allowed. It will take discussion and creative planning to take full advantage of this, or any other, out-of-the-box (or off-the-grid) idea for repurposing the abundance of used tires and other “trash” materials in ways that are beneficial without creating additional messes. I hope that we can agree that these conversations are worth the effort, if only for the purpose of taking care of the Earth and everything that is in it.