. "of the hedgehog) and small mammals increases with increasing proximity to motorways and with increasing traffic volumes.???It should be mentioned that, in the UK at least, four-star (i.e. leaded) petrol has been almost entirely replaced by unleaded (only 0.5% of outlets remain, largely to fuel classic cars).???Nonetheless, many of the heavy metals and other pollutants that may be present along the" . . .