A new paper says that exposure to a banned neonicotinoid insecticide causes changes to the genes of the honeybee. The paper was written to support the recent decision taken by the European Commission to temporarily ban three neonicotinoids amid concerns that they could be linked to bee deaths.

Honeybees pollinate one-third of the food that we eat and the experiment looked at changes in the activity of honeybee genes linked to one of the recently banned neonicotinoids, imidacloprid.

The work (in press), led by Dr. Reinhard Stöger, Associate Professor in Epigenetics in the University of Nottingham's School of Biosciences, found that a very low exposure of just two parts per billion has an impact on the activity of some of the honeybee genes.

The researchers conclude that cells of honeybee larvae had to "work harder" and increase the activity of genes involved in breaking down toxins most likely to cope with the insecticide. Genes involved in regulating energy to run cells were also affected. Such changes are known to reduce the lifespan of the most widely studied insect, the common fruit fly, and lower a larva's probability of surviving to adulthood.

Stöger said, "Although larvae can still grow and develop in the presence of imidacloprid, the stability of the developmental process appears to be compromised. Should the bees be exposed to additional stresses such as pests, disease and bad weather then it is likely to increase the rate of development failure."

The study was funded by The Co-operative Group, a $15 billion UK company, as part of its Plan Bee campaign. Chris Shearlock, Sustainable Development Manager at The Co-operative, said: "This is a very significant piece of research, which clearly shows clear changes in honeybee gene activity as a result of exposure to a pesticide, which is currently in common use across the UK.

"As part of our Plan Bee campaign launched in 2009 we have adopted a precautionary approach and prohibited the use of six neonicotinoid pesticides, including imidacloprid, on our own-brand fresh and frozen produce and have welcomed the recent approach by the European Commission to temporarily ban three neonicotinoid pesticides as this will allow for research into the impact on both pollinators and agricultural productivity."

DERECKA K, BLYTHE MJ, MALLA S, GENEREUX DP, GUFFANTI A, PAVAN P, MOLES A, SNART C, RYDER T, ORTORI CA, BARRETT DA, SCHUSTER E and STÖGER R, 2013. Transient exposure to low levels of insecticide affects metabolic networks of honeybee larvae PLOS ONE.