10
Mar
Pyrethroids Found to Impair Bee Reproduction
(Beyond Pesticides, March 10, 2010) A study investigating the sublethal effects of pyrethroids, bifenthrin and deltamethrin on honeybees finds that the chemicals significantly impair the pollinators’ reproduction. The researchers also point out that the concentration of each pesticide that produced adverse effects in the experiments was at or below those that bees could encounter while pollinating treated crop fields. “Effects of sublethal concentrations of bifenthrin and deltamethrin on fecundity, growth, and development of the honeybee Apis mellifera ligustica” published in the March issue of Environmental Toxicology & Chemistry, investigated the effects of the two pesticides at sublethal concentrations on fecundity, growth, and development of honeybees were examined with the feeding method for a three-year period (2006-2008). It was shown that both bifenthrin and deltamethrin significantly reduced bee fecundity, decreased the rate at which bees develop to adulthood, and increased their immature periods. Queens in the control group in 2006 laid a little more than 1,200 eggs each day, compared to not quite 900 a day in the bifenthrin group and roughly 600 per day in the deltamethrin group. In general, the hatch rate of pyrethroid-exposed eggs was also significantly depressed. The success rate of hatchlings, that is the share that […]
