As a chemist, the suggestion of a risk associated with an inert material like shredded tire crumbs seemed chemically implausible, but having seen the documentary I chose to do a bit more research. What I found reassured me. The toxicological research on the topic was pretty much unanimous in saying that rubber tire crumbs do not appear to pose a significant risk to players.
So the question arises: Why all the fuss? Well the answer is one of risk communication and a misunderstanding of chemistry.
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