Three pesticides routinely used by European farmers pose an "acute risk" to honey bees, according to the European Food Safety Authority (EFSA). In three studies
published yesterday, EFSA addresses long-standing concerns of beekeepers and scientists about dwindling populations of pollinator bees, which are essential
to farming and natural ecosystems.
The review, requested by the European Commission last year and carried out by EFSA's Panel on Plant Protection Products and their Residues, assesses the
risks posed to bees by three types of neonicotinoid insecticides: clothianidin, imidacloprid, and thiamethoxam. This family of pesticides has been used by
European farmers since the early 1990s and is sold by Syngenta in Basel, Switzerland, and Bayer CropScience in Monheim, Germany. EFSA says none of the
three should be used on crops that are attractive to bees, such as maize, rapeseed, or sunflower. Although the study does not link the pesticides to the
collapse of whole bee colonies, the agency's advice could open the door to a neonicotinoid ban in the European Union. Several countries, including France
and Slovenia, have already restricted the compounds' use in the past years.
"With hindsight, EFSA appears to agree that the [initial approval procedure for neonicotinoids] was not thought through at the time," says ecologist David
Goulson of the University of Stirling in the United Kingdom.
Syngenta has already pledged to defend its product, slamming EFSA's study as "hurried" and poorly researched. John Atkin, the company's chief operating
officer, said in a statement issued yesterday that "this report is unworthy of EFSA and of its scientists." In a
more gently worded statement, Bayer CropScience pointed out that "poor bee health and colony losses are caused by multiple factors," incriminating in particular the parasitic Varroa mite.
Antonio Gómez Pajuelo, biologist and owner of beekeeping consulting company Consultores Apícolas in Castellón, Spain, agrees that the toxicity of
neonicotinoids is just one of many factors that affect bee health—including, for instance, parasites and climate change. But he says that Europe's
approval procedures for insecticides are "too lax": In particular, they fail to assess the long-term effects of small, nonlethal doses on bee health.
The previous generation of widely used farming insecticides, the pyrethroids, were typically applied to the crops by spraying the field using a tractor;
neonicotinoids are applied only to the seeds, a procedure called "seed dressing." At the time, this appeared to be a superior method, Goulson explains:
Farmers save time and money by buying pretreated seeds, and the chemicals are applied to only the crop instead of to the whole field.
But neonicotinoids are systemic pesticides, meaning that they are present in the whole plant—including the nectar and pollen that bees feed on, or the
droplets of sap exuded by maize seedlings. Besides, some toxic dust is created during sowing that can blow into the environment, and the chemicals can
build up in the soil. EFSA's study examines these modes of contamination, which Goulson says were overlooked when neonicotinoids were first approved for
sale.
Both Syngenta and Bayer seem to have prepared for a counterattack: They funded another study, released
one day before EFSA's, by the Humboldt Forum for Food and Agriculture, a small think tank funded by Bayer CropScience and other businesses. It claims that
banning neonicotinoids could cost 50,000 jobs and cause economic losses worth €17 billion over 5 years in the European Union.
Goulson dismisses this study as unsound "propaganda," pointing out that the industry is trying to protect a profitable market. Another study, published in 2009 by researchers at France's National
Institute for Agricultural Research and the Helmholtz Centre for Environmental Research in Germany, put a €153 billion price tag on the annual economic
value of pollination worldwide.
E.U. government officials will discuss neonicotinoids on 31 January, a commission spokesperson told reporters on Wednesday. He added that the commission
was ready to "take the necessary measures" against the three chemicals if scientific evidence keeps piling up.