The use of the chemical insecticide malathion is proving controversial in the western Manitoba city of Brandon.

The Wheat City has been fogged three times so far this year under a provincial order, the first time the city of 40,000 has used the broad-spectrum organophosphate insecticide in 30 years.

On Thursday, provincial health officials ordered more fogging in the community in an attempt to control the population of the adult mosquitoes that carry West Nile virus.

Local author Di Brandt has started a petition against the fogging, saying the health risks of using the pesticide outweigh the benefits.

"I think that the Manitoba government has been very irresponsible in the way it has advertised the risk of West Nile virus and also the risks of malathion spraying," she told CBC News.

Brandt's petition has attracted the signatures of more than 400 people so far, including Tara Kindle's.

"I just feel like my children are so exposed to so many chemicals, whether it be from our drinking water or, you know, all the pollutants we're forced to ingest on a regular basis," Kindle said. "This is just another one to add to the long list."

Connor Ubell says he's not only opposed to the chemical being used to control mosquitoes — he's also opposed to the government's ordering municipalities to do so without listening to local concerns first.

FOGGING DETAILS

Fogging takes place in the evening and overnight hours when the weather permits. Temperatures must be at least 13 C and there can be no significant wind or rain. Provincial officials suggest people who wish to reduce their exposure to malathion: Close doors and windows. Turn off air conditioners. Bring in clothing and toys from the outdoors. After fogging, household items left outdoors and homegrown produce should be washed before use.

"Our government's supposed to be run in a way where the people have a choice, when really this is not a choice we had. It was more of an authoritarian thing," he said.

Brandt said she plans to present her petition to Health Minister Theresa Oswald and Dr. Joel Kettner, the province's chief medical officer of health.

Malathion used safely in Manitoba: Kettner

Kettner says he realizes the use of malathion is controversial, but says Manitoba's use of the pesticide is well within safe guidelines.

Tests on people exposed to malathion at the levels used in Manitoba have shown no traceable amounts in the body, Kettner said.

"Another feature of malathion which I hope everyone understands is that it doesn't stick around like some other chemicals that are of concern in the environment," he said.

"It doesn't build up in the food chain. It breaks down very quickly into natural elements, and within days or weeks there isn't a trace of it, even if you look for it with the most sensitive measures."

New orders under the province's Environment Act were issued Thursday to fog with malathion in the town of Morris and the city of Portage la Prairie.

Fogging based on previously issued orders will continue in Altona, Brandon, Carberry, Morden, West St. Paul, Winkler and in parts of north, east and west Winnipeg.

58 West Nile cases reported this year

Kettner said the province uses malathion only when provincial experts determine it is likely to prevent one or more cases of the most serious neurological form of West Nile virus.
 
There have been four such cases in Manitoba this summer, and one death. A total of 58 human cases of the disease have been reported to the province this year.
 
Meanwhile, more Manitobans have been tested for the virus this year than in previous years.

About 1,000 people have been tested for it so far this summer — four times the number tested last year and higher than 2005 and 2004.

Figures were not available for 2003, the year Manitoba saw 143 reported cases of West Nile — the highest number so far.

Kettner says people get the test through their doctor, either when they have symptoms or when their doctor decides they should be tested.  
 
Health officials want doctors to have their patients tested if they have any suspicions they may have been bitten by infected mosquitoes, Kettner said.

Most people who are bitten by a mosquito infected with West Nile do not become ill. For those who do, the symptoms are usually mild. In some cases, the virus causes serious illness, and sometimes death.