Edmonton is the last municipality in Canada to use this very potent and persistent neurotoxin to kill mosquitoes when safer alternatives exist.  This organophosphorous pesticide is known for its damaging effects on the human nervous system.  Children are especially vulnerable.  This insecticide also kills all the predators to the mosquito and is toxic to other species such as bees, birds and small mammals.  Found in arctic ice dating back to 1972 means it has the ability to last a long time in the environment and move long distances.  Animal studies shows it's potential to bio-accumulate.  There are no valid reasons to continue its use!