UPDATED 1.53pm: Auckland Council is being accused of putting profit before people with its continued use of glyphosate.

The Weed Management Advisory claims to have documents which show the active ingredient in Roundup is now being used in most of the city, despite a World Health Organisation agency finding last year that glyphosate is probably carcinogenic.

Advisory spokeswoman Hana Blackmore believes Auckland Council and Auckland Transport are increasing its use without consulting the public first.

"This new Super City and it's CCO's believe the top line and the middle line is money," she said.

"They believe it doesn't matter about the health effects, it doesn't matter that it's not good for the children."

Green Party MP Steffan Browning said there was no need for councils to use it when there were safe alternatives for controlling weeds, such as hot water treatment, weed trimmers and mulching.

"Our parks and neighbours should be safe places for children, free of harmful sprays that risk making people seriously ill," he said.

Councillors last year rejected a call to replace glyphosate with water-based alternatives.

The manufacturers of Roundup have also disputed the World Health Organisation's findings.