Clot ("Clot" ) gurgled happily, sounding much like
they were saying:

I'm not wishing to enter a dribbling drivel conversation, but Adrian I
have been involved in point source and diffuse inputs of heavy metals
into the environment. Tyres contain zinc. I had expected that most would
have been contributed on motorways and dual carriageways. A university
research project currently ongoing is indicating that at least higher
concentrations are generated in the urban environment and possibly
greater quantities. The work is ongoing.

Are tyres the only source of Zinc?