Pesticides Cause Massive Bee Kill in Wilsonville

The Oregonian is reporting that the discovery of 50,000 dead bees in Wilsonville was caused by a pesticide called Safari.

The state is investigating any violation of pesticide laws, which could take up to four months, said Dale Mitchell of the Agriculture Department. 

Mitchell said the bee deaths, the largest documented die-off of bumblebees, could prove important in determining the use and regulations of Safari and other insecticides in the United States. 

Safari's main ingredient is dinotefuran, a neonicotinoid. There are two main kinds of neonicotinoids, both of which are general use insecticides. Safari is a member of the nitro-group.  Research published in 2012 shows these are generally more toxic to bees than the other type. The European Union issued a temporary ban on three other kinds of nitro-group neonicotinoids, which will go into effect this December.