The Pest Management Review Agency plans to ban one neonicitinoid and put two others under special review.
The ban has been proposed because imidaclorprid accumulates in waterways where it harms aquatic insects.
The agency said that based on findings, the continued use of this neonicitinoid is not sustainable.
Clothianidin and theomethoxam have been put under special review.
The Pest Management Review Agency said it has found that the neonicitinoids dissolve in water and run off into waterways at volumes it previously did not know.
Agriculture uses neonicitinoids as seed treatments. They are highly effective in controlling crop-devouring insects.
There are huge controversies in Ontario because the provincial government moved to curb their use before it had conclusive scientific evidence of harm.
Its curbs are also controversial because it requires farmers to hire consultants to determine whether there are pests in fields before they can buy seed treated with neonicitinoids.
That is further controversial because the majority of consultants have been excluded from providing this service because they work with farm supply companies that market neonicitinoids.