A group of scientists affiliated with the International Union for Conservation of Nature (IUCN) recently conducted a meta-analysis of 800 peer reviewed reports of the systemic pesticides neonicotinoids and fipronil. The results of this analysis raise questions as to the continued approval of the insecticide by U.S. regulators.
The group’s report, known as the Worldwide Integrated Assessment (Report) finds “that neonics pose a serious risk to honeybees and other pollinators such as butterflies and to a wide range of other invertebrates such as earthworms and vertebrates including birds.” Furthermore,
In reviewing all the available literature rather than simply comparing one report with another, the [Report] has found that field-realistic concentrations of neonics adversely affect individual navigation, learning, food collection, longevity, resistance to disease and fecundity of bees. For bumblebees, irrefutable colony-level effects have been found, with exposed colonies growing more slowly and producing significantly fewer queens.
Neonics are different from other insecticides. “Applied to the soil or doused on seeds, neonicotinoid insecticides incorporate themselves into the plant’s tissues, turning the plant itself into a tiny poison factory emitting toxin from its roots, leaves, stems, pollen, and nectar.” With systemic pesticides, “the chemical is in the bloom. So bees searching for nectar now can come into contact with pesticides too.” (More information on neonics and the disappearing bees can be found here). The systemic pesticides are not only widely used in agriculture but traces of them are also common in backyard nurseries.
The Report found that the animals most affected by neonics are earthworms and other terrestrial invertebrates, followed by bees, butterflies and other insect pollinators, which are followed by freshwater snails an, water fleas and other aquatic invertebrates. While vertebrate animals are “generally less susceptible, bird populations are at risk from eating crop seeds treated with systemic insecticides, and reptile numbers have declined due to decline of their insect prey.”
Dr Jean-Marc Bonmatin, one of the leading authors of the Report, said in a statement published by IUCN that “[t]he evidence is very clear. We are witnessing a threat to the productivity of our natural and farmed environment equivalent to that posed by organophosphates or DDT.” In fact,”[f]ar from protecting food production, the use of neonics is threatening the very infrastructure which enables it, imperilling the pollinators, habitat engineers and natural pest controllers at the heart of a functioning ecosystem.”
Unlike regulators in the United States, the European Union took a proactive step last year to protect bees when it issued a two year ban on three neonicotinoids (clothianidin, imidacloprid and thiametoxam). The Environmental Protection Agency, however, is not banning nor restricting the use of neonicotinoids. Despite numerous calls by environmental groups for an immediate ban the agency says it is re-evaluating the insecticide through the registration process, never mind the fact that the original approval of neonicotinoids has been heavily criticized.
But not all U.S. regulators act in unison. In an interesting policy break with its sister agency, the Fish and Wildlife Services recently announced a plan to eliminate neonicotinoid insecticides in wildlife refuges in the Pacific Region, citing adverse affects on non-target as a top concern.
Authors of the Report urged government agencies to take a precautionary principal and start considering or making phase-out plans for systemic pesticides. The Report will be published in the peer-reviewed Journal Environment Science and Pollution Research.