More than 650,000 people have called for a ban on spraying chemical weed killer in Bristol's parks. and other public spaces.
It's after the World Health Organisation found an ingredient called glyphosate, which is common in most weed killers, could be a cause of cancer.
Since then many countries have restricted the use - as has Glastonbury Council.
Harriet Williams, Co-ordinator at Pesticide-safe Bristol Alliance says the risk it poses to human health is only one of many dangerous effects.
Bristol Councillors will meet to debate its use on 15 March.