It’s concerning that Health Canada may have cast its net too wide in its decision to ban two more neonicotinoid seed treatments without a full set of information about whether such a dramatic move is required in Western Canada.

Health Canada’s Pest Management Control Agency admits its information from Western Canada on whether neonics are a danger to aquatic insects, which are important in the food chain for fish and birds, isn’t as robust as the data from Quebec and Ontario, but it appears to be going ahead with a blanket ban on the chemicals anyway.

We are not saying the PMRA hasn’t done good research. The agency says its scientists have reviewed more than 1,000 scientific studies and received more than 55,000 comments.

But does it have enough information to decide whether a blanket ban is necessary?

In 2016, the PMRA announced that after a special review it would remove imidacloprid from the market within three to five years, pending a review period, which has since been completed. In Western Canada, imidacloprid helps to control wireworms in wheat. A decision is expected this year. A similar process resulted in clothianidin and thiamethoxam, which help control flea beetles in canola, being removed, by 2021 for crops with alternatives available, and 2023 for uses that do not yet have viable alternatives. Ninety-day review periods offering a chance for farm groups to comment will be held before the final decision is made.

Neonics first became a target because it was thought that they were stressing bee colonies, which made bees more susceptible to weather and disease. But the PMRA’s decision isn’t about protecting bees. Research shows neonics build up in the soil and leak into surface water, which can then be absorbed by aquatic insects.

Health Canada says the use of alternatives to neonics in the environment hasn’t been studied with respect to a chemical ban, but since the alternatives are registered chemicals, they are deemed to be safe.

The neonics ban will place Canada offside with the United States. The European Union has also banned neonics for field crops, and while yields have largely held, rapeseed acres have declined and costs have increased for farmers.

Each year, up to 63 million acres are planted in Western Canada, most of them in wheat and canola.

Removing neonics from the marketplace will require farmers to turn to more expensive diamide seed treatments, or spray foliar chemicals, all of which are toxic to bees and other insects, since they will likely see heavier use.

There is also the timeliness issue. Flea beetles can wipe out a canola field in a matter of days, making spraying an uncertain proposition.

The Environmental Monitoring Working Group, which is funded by grower associations, suggests spikes in neonics levels in surface water in Western Canada might be explained by greenhouse operations or urban uses. In Central Canada, higher levels of neonics in surface water have been detected in such cases.

The federal government has been encouraged in the past to institute a full surface-water testing program in the Prairies, but testing remains sporadic.

The PMRA is about to take away a major tool for farmers, with environmental advantages that are unclear, given the increase in use of other chemicals. Before such a major decision is made, vigorous testing of surface water should be completed in the West, allowing decisions to be made on hard science.

Karen Briere, Bruce Dyck, Barb Glen, Brian MacLeod and Michael Raine collaborate in the writing of Western Producer editorials.