EDN Issue 130 - Now Available
Published
2016-01-25
In This Issue:
- Tire Contaminants from a Container Gardening Perspective
- Cyantesmo Paper for Detecting Cyanide
- Effective Use of Workshops in Agriculture Extension
- Echoes From Our Network
- From ECHO’s Seed Bank: Vegetable Seed Highlights (See PDF Version)
- Books, Websites and Other Resources (See PDF Version)
Excerpt: Tire Contaminants from a Container Gardening Perspective
When trying to find affordable planting containers in the developing world, organizations and workers all over have promoted the use of a readily-available waste resource: tires. Over the years, many have asked whether or not tires contain harmful chemicals that could potentially be taken up by your crops. This article is written to communicate what we found from our search of literature on this topic.
Much of the literature on the subject pertains to tires that have been recycled into small particles. In comparison to the side wall of a tire container, the tire surface area in contact with growing media is much greater with small chunks of rubber. Much of the information available also pertains to toxins in the ash of burnt tires, or those leached from tire material subjected to strongly acidic solutions. Tire garden containers, of course, are not being converted to ash.
Furthermore, the media used to grow plants in tires is not nearly as acidic as the solutions often used to study contaminants in tire leachate.
Nevertheless, tires do contain trace amounts of four metals that are known to be toxic to humans. Most of the discussion below relates to metallic elements, but there is also brief discussion of organic contaminants. The article concludes with suggested practices to make tire gardening as safe as possible...