A long time ago I read that your lawnmower could produce more pollution than your car.  At first this didn’t sound right, because lawnmower engines are so small.  But they are unregulated and don’t have all the sophisticated pollution control equipment of autos.  The article Cleaner Air : Gas Mower Pollution Facts says a mower produces 11x the pollution of a car.  I believe it.  The good news is I see lots of new electric and battery powered mowers at the stores.  Things like this can make a big difference.  So before you rush out and buy that Tesla, get a new mower!   Electrics are quieter, too.  Next big change should be heavy equipment used at construction sites.