Tuesday, January 28, 2014

Honeybees' Larvae Killed by Poisoned Pollen

Scientists say in a new study that pollen loaded with a deadly cocktail of pesticides is killing honeybee larvae in their hives Commonly used pesticides chlorothalonil, fluvalinate, coumaphos and chloropyrifos have statistically significant effects on larvae survival. Chlorothalonil was found to be the most toxic. The research is published in the PLOS One journal. The scientists involved in the study urges the United States EPA to change its pesticide regulations to assess the risk of poisoning honeybee larvae by using these pesticides. Under current regulations only the risks to adult honeybees is considered. Pollen is used by adult bees to feed their offspring and on average six insecticides are present in pollen brought back to the hive. The research team also discovered that an "inert" chemical used as a solvent to pesticides, N-methly-2-pyrrolidone, is highly toxic to larvae at low levels. This chemical is generally considered to be safe, so there is no limit on its use and its residue in the environment is unmonitored. Chronic exposure to toxins in the environment is contributing the decline of honeybees worldwide. Recently, research has revealed a whole class of pesticides, neonicotinoids, causes neurological problems for bees perhaps leading to colony collapse.