The federal government already has a rigorous process for assessing pesticides, a Health Canada representative told a British Columbia committee today.

"Certainly science is the basis for all Health Canada decisions on pesticides and certainly the approach is precautionary," said Lindsay Hanson, a stakeholder engagement and outreach manager with the pest management regulatory agency.

Based in Ottawa, Hanson was in Victoria to talk to the special committee on cosmetic pesticide use. The committee was appointed after Premier Christy Clark said she favours creating a law to restrict the cosmetic use of pesticides in the province.

Earlier this week Clark appointed Kootenay East MLA Bill Bennett to chair the committee, an appointment criticized by Wilderness Committee campaigner Ben West. Bennett told The Tyee that any government action needs to be based on science rather than emotion.

The Health Canada agency has 350 scientists who consider large numbers of studies, Hanson said. A photo in his slide presentation showed shelves of some 60 binders which he said were each six-inches thick and were all for one chemical. "That's what our scientists look at," he said.

The agency looks for the smallest dose of a chemical that will harm the most sensitive animal, then it divides that amount by 100 to determine the "acceptable exposure" level, he said. They then calculate the likely exposure when the chemical is used according to its label. It won't be approved unless that likely exposure is below what's calculated as acceptable, he said.

Committee members questioned the agency's ability to ensure the use of toxic chemicals is safe for people or the environment. Alberni-Pacific Rim MLA Scott Fraser asked how it can be possible to take a precautionary approach when it is difficult to know the quantity of pesticide being used and what the cumulative amounts are.

He noted, "We know things that have been deemed safe before are no longer deemed safe."

Victoria-Swan Lake MLA Rob Fleming asked what research the agency has done on compliance rates and whether people use pesticides as directed on the label.

"When we produce the label, we're looking for 100 percent compliance," said Hanson. The labels are legal documents that need to be followed, he said. "Those directions for use are there for a reason."

He said it would be difficult, if not impossible, to study the effects of a mix of various chemicals in the environment, though individual chemicals are thoroughly tested. "Pesticides are among the most rigorously tested substances in the world," he said.

And responding to a question from Richmond-Steveston MLA John Yap, he said, "The chemicals themselves have a potential to be hazardous, that's why we have a strong regulatory system in Canada."

Westside-Kelowna MLA Ben Stewart, an owner and founder of Quail's Gate winery, spoke about the "concern or perceived concern" around pesticides. "I don't know how we help the consumer understand we have a safe system," he said, observing that some products have been pulled off the market.

Provinces have the authority to put conditions on use beyond what Health Canada allows, Hanson said. "We have to use what is referred to as a science-based process."

"While Health Canada confirms that (in its view) the risks of pesticides are 'acceptable', you need only read the government-approved labels for these pesticides to realise that they are not 'safe' and pose significant risks to human health and the environment," Andrew Gage, a staff lawyer with West Coast Environmental Law observed in a blog posting yesterday.

Some 76 percent of British Columbians want a law to restrict the cosmetic use of pesticides like ones already in place in Ontario, Quebec and Nova Scotia, he said.

The committee next meets on Oct. 26 in Victoria. A transcript of today's proceedings is available here.

Andrew MacLeod is The Tyee’s Legislative Bureau Chief in Victoria. Reach him here.