Toxicity of Organic Insecticides to Honey Bees: Contact Spray and Field Tests1

Publisher Website
Google Scholar
Abstract
Five organic insecticides were sprayed directly on honeybees. The decreasing order of toxicity was: 3 parts gamma benzene hexachloride- 5 parts DDT, gamma benzene hexachloride, chlordane, DDT and toxaphene. Comparison with previous tests indicate that sprays are more toxic than dusts when applied directly to bees. Bees inside large cages were allowed to work cotton which had been treated with insecticides. Toxaphene spray exhibited little toxicity to bees, but 2 parts toxaphene- 1 part DDT spray, and dusts of 20% toxaphene, 10% DDT, 3% gamma benzene hexachloride, 3% gamma benzene hexachloride-5% DDT, and 10% chlordane killed from 8.2 to 10.4% of the bees in 8 applications. Applications of chlordane, benzene hexachloride, and benzene hexachloride-DDT dusts resulted in a marked decrease in the number of bees gathering nectar from the cotton. Little repellency due to DDT or toxaphene was noted.