Executives of industrial agriculture seem to suggest that opposition to neonicotinoids is based on non-science and hysteria. However, scientific researchers around the world have overwhelmingly shown the negative effects of neonics. So let’s look at that evidence.
Neonicotinoids target early season insect pests like seedcorn maggot, wireworm, and bean leaf beetles. These pests appear sporadically; they are not found everywhere, or every year. So most neonic treatments are applied ‘just in case’. This is like taking antibiotics all winter ‘just in case’ you get sick.
The EPA has also reported that neonic seed treatments are ineffective against the two major soybean pests - soybean aphids and the bean leaf beetle. “This is because the limited period of (neonic) bioactivity in soybeans (three to four weeks) does not usually align with periods of soybean aphid presence/activity”. “Similarly, neonicotinoid seed treatments are not effective in controlling bean leaf beetles as this pest occurs too late in the season.”
There is increasing evidence that neonicotinoids decrease populations of insects, birds, fish, amphibians and reptiles. Scientists from Radboud University in the Netherlands and the Dutch Centre for Field Ornithology and Birdlife Netherlands (SOVON) found that in areas where water contained high concentrations of imidacloprid (a common neonicotinoid), bird populations tended to decline by an average of 3.5 percent annually.
Neonicotinoids affect birds, fish, and other animals in two ways. The first is by ingestion. A 1992 study by the EPA found that House sparrows would only have to eat one and a half beet seeds coated with imidacloprid to die. Even a quarter of a treated seed would have sub-lethal effects, including damage to DNA and the immune system.
The second way neonicotinoids can affect birds, fish, and other animals is by killing their food sources. This would affect their growth, breeding success and survival.
We are animals too. The European Food Safety Agency (EFSA), reports that recent research suggests that acetamiprid and imidacloprid “may affect the developing human nervous system”.
And here are a couple of other unintended consequences of neonicotinoid insecticides: Researchers at Penn State University noted in the Journal of Applied Ecology that neonics increase slug populations and the damage they cause. Slugs are kept in check by predatory insects, especially ground-foraging beetles. Neonics have no direct affect on slugs. However, neonics are systemic which means that they permeate all parts of a plant including the leaves that slugs love, so the slugs become contaminated with neonics, too. Essentially, the slugs become the insecticide that kills the beetles and other predatory insects. Without their natural enemies, slugs proliferate.
Then there’s the spider mites. PLOS (Public Library of Science) reports that applications of neonicotinoids are associated with severe outbreaks of many species of spider mites.
The neonic issue is bigger than a disagreement between beekeepers and farmers. It’s a plea for the butterflies, beetles and birds. It’s a call for evidence-based decisions. It’s a quest for courage in the face of heavily financed opposition. It’s a wish of our great-great-grandchildren who should be included in this discussion.
Celeste Lemire is Chair of the Food Diversity Committee of the Council of Canadians, London Chapter
