This is a follow up to Elisa’s article on the topic, which I was prompted to write because a nice lady, Olivia Taylor in Mitchell South Dakota, is reported online making DIY cat shelters from tires. Very laudable but could she do better? My conclusion after some rather difficult research is that tires are made from a host of compounds and chemicals many of which can cause harm and therefore to play safe they are unsuited as cat shelters. Please read on.
These harmful substances can leach out of the tire (tyre) over time. However, the leaching is slow but how slow?
A lot of gardeners use old tires to make containers in which to plant vegetables. There is a big discussion about their suitability as tire chemicals can leach into the vegetables.
Sheila planted potatoes in tires:
One year, my father and I planted potatoes in tires. Just put on another tire and add dirt. We had lots of potatoes with seven high. PVC pipe with holes in it to water the plants. Problem was that they tasted like tires. Since then, I am not a fan of tires for living or gardening. — Sheila
On the subject of using tires for growing vegetables, David on the thegrownetwork.com website concluded that tires were unsuitable.
After multiple hours of research, I am now leaning against tire gardening — David
Nowadays tires are largely recycled. But it is a known fact that they contain toxic substances (my thanks to David and Brighton Permaculture Trust):
- Natural rubber
- Synthetic rubber compounds, including Butadiene—known carcinogen
- Solvents: Benzene—known carcinogen, Styrene—anticipated to be carcinogenic, Toluene—has negative health effects, Xylene—irritant, & Petroleum naphtha
- Polycyclic aromatic hydrocarbons: Phenols—some are endocrine-disruptive, Benzo(a)pyrene—linked to cancer
- Heavy metals: Zinc, chromium, nickel, lead, copper & cadmium
- Carbon black—possibly carcinogenic
- Vulcanising agents: Sulphur & zinc oxide
- Polychlorinated biphenyls—known carcinogen
- Other synthetic chemicals
As mentioned these are locked in but can gradually leach out.
…..there are significant concerns regarding the environmental and toxicological impact of chemicals that can be released (leached) from car tire rubber during weathering and numerous studies have examined the toxicity of tire leachate….Leachates or extracts of rubber tire have been shown to produce toxicity in a variety of aquatic organisms, including fish, amphibians, invertebrates, bacteria and plants..and in human lung cell lines.. — Identification of Benzothiazole Derivatives and Polycyclic Aromatic Hydrocarbons as Aryl Hydrocarbon Receptor Agonists Present in Tire Extracts.
You have to be drawn to the conclusion that there are potential or actual health and safety issues surrounding the use of tires as cat shelters. A problem is that, as yet, we don’t have enough knowledge to decide how harmful these tire compounds are when a cat is in close proximity to them for a long time when sheltering inside a tire. I think the tightly enclosed space, the proximity and the time spent in that space are important factors in making a decision.
Our lack of complete knowledge combined with potential danger means that we have to play safe and not use tires as cat shelters when there are many safer alternatives such as modified water coolers or storage units (click to read). Click here if you want to read Elisa’s article.
SOME ARTICLES ON TOXIC TO CATS: