Re: tires

I'm sorry that I cannot cite the original reference--I cannot 
remember it, and I don't have time to look it up, but...
the study was done with tires that were to be "landfilled"
in ponds.  Dumped.

Anyway, the upshot of the research was that tires without metal
belts were "stable," without any apparently harmful contaminants
or breakdown products leaching into water.  However, tires with 
exposed metal belts (ruptured, blown, whatever) leached trace 
amounts of heavy metals into water.  

It was research conducted in the US.

> Used tires are being recycled in many ways-road beds, building materials for
> houses, fuels for kilns, erosion stablization, shredding to improve turf field
> drainage.
>  But---What about food production? Creating raised beds out of used tires and
>  growing vegetable crops.
>  What are any possible problems with this (e.g., heavy metals, xenobiotics)?
>  Current thought is that tires are stable, with the only problems being in
>  rodent and insect populations increasing.  any ideas??