Polo Bikes

Nice when it does break, lots of little asbestos like shards in yer skin.

Splinters of carbon fibre should be less risky than wood splinters when embedded in skin; The material won't degrade so the risks are contaminants drawn into the wound.

...
When carbon fibre was fed into a hammer mill, only low concentrations of dust of respirable size could be produced and less than 1% of the respirable carbon particles were fibrous. The dust cloud contained a few transparent fibres, probably glass, of respirable size. When the dust was inhaled by guinea pigs...[snip]
No pathological effects were observed.

So... no asbestos-like effects from traditional Carbon Fibre.

Carbon Nanotubes, on the other hand, are shaped like asbestos fibres, and are found to behave like asbestos fibres.