Too soon to say if report will affect malathion use in Manitoba

The Manitoba government says it's too soon to tell whether a report from the World Health Organization (WHO) warrants any action with regards to the widespread use of malathion, an insecticide the city uses in its mosquito nuisance fogging program.

Mayor Bowman, Manitoba government weighs in on WHO malathion report

Mosquito-fogging trucks will roll down Winnipeg streets Thursday night, for the first time this year. (CBC)

The Manitoba government says it's too soon to tell whether a report from the World Health Organization (WHO) warrants any action with regards to the widespread use of malathion, an insecticide the city uses in its mosquito nuisance fogging program.

The International Agency for Research on Cancer (IARC), a WHO agency, published a preliminary report Friday calling malathion “probably carcinogenic.”

Glyphosate, a key ingredient in Monsanto’s widely used lawn care and farming herbicide RoundUp, was also deemed likely carcinogenic — something Monsanto has slammed in numerous reports in recent days.

The City of Winnipeg released a statement on the weekend saying it will be reviewing the report with Health Canada, which licenses and regulates malathion use by municipalities.

Bowman said community health will be at the heart of any decisions that are made with respect to fogging protocol.

"Dealing with the mosquitoes is something that Mother Nature throws at us every year and we want to do it in a way that's responsible for the needs of Winnipeggers’ health," said Bowman.
Taz Stewart, former lead entomologist with the City of Winnipeg, says until conclusive proof is provided showing malathion is poisonous to humans, Health Canada's guidelines on its usage hold. (CBC)

Health Canada said it is waiting on the full WHO report before making any judgment on how to move forward.

The Manitoba government said Monday it is also reviewing the report and working with Health Canada and the city “to see if any actions are warranted.”

"It is too early to say if this report will affect the use of this pesticide in the province," a spokesperson with the province said.

“As a rule, when used in a proper manner and within appropriate application rates, malathion is not considered to pose an increased risk to public health. There are safe work procedures and programs in place to control the hazard for groups that work directly with the product and who might be at higher-risk of exposure.”

The city's former lead entomologist Taz Stewart said the report is tentative in nature and at the moment Health Canada's malathion guidelines still hold water.

"It's a report where you have to question the data, the wording they use in air quotes, 'probable cause,''" said Stewart. "Probable cause doesn't really give you a sound reason ... you have to dig deeper into these articles and find out why they're saying these things.”

Until proven otherwise, Stewart maintains malathion is safe so long application directions are followed.

"Those products are deemed safe as per you following the labelled directions," said Stewart. "If you use it outside of that, that's where maybe there could be an issue."

Stewart has echoed a sentiment shared by Dr. Joel Kettner, medical director of the International Centre of Infectious Diseases.

"This has not really moved the scientific markers in any significant way with regards to the decision making that needs to be made around the world for the use of a substance which has the potential to prevent serious diseases," Kettner, an associate professor at the University of Manitoba, said Sunday.
Monsanto is based in Winnipeg on the University of Manitoba Fort Garry campus. (Jeff Stapleton/CBC)

Monsanto, based in Winnipeg, said the report findings on RoundUp and glyphosate are inconsistent with previous studies done by Health Canada that deemed the chemical safe.

"It is absolutely not carcinogenic, in fact it's not what Monsanto is saying, it's what third party regulatory agencies and scientific bodies around the world are saying," said Trish Jordan with Monsanto. "Glyphosate is the most widely used herbicide in agricultural productivity, it’s been around for 40 years and has a 40-year history of safe use."


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