It's been two years since the cosmetic pesticide ban went into effect in Ontario and Environment Minister John Wilkinson says during that time there has been a noticeable improvement in water quality in urban areas.

Wilkinson said Wednesday that since 250 pesticide products were removed from store shelves in 2009, the concentration levels of 2,4-D — one of the most common pesticides — has been found to be significantly lower in 10 urban streams.

"The research that was done by the province looked at the concentration before and after the ban came into effect, and in some cases those drops are as much as 97 per cent reduction in urban streams," said Gideon Forman the executive director of the Canadian Association of Physicians for the Environment.

And the province is looking at adding more products to the banned list.

"Some additional products will no longer be readily accessible on store shelves," Wilkinson said.

There has been some opposition in the past to the ban on 2,4-D but Wilkinson says the Ontario government is standing by its decision, saying people's health is at risk.

So far six Canadian provinces — Quebec, Ontario, New Brunswick, Prince Edward island, Nova Scotia and Alberta — have banned cosmetic pesticides.