health canada has authority over anything entering canada related to any health implications either real or implied, they supersede any law either written or not unless theres a law specific to said item for entering canada.
for anything i mean food, plants etc. not just nic.
you would need to prove to health canada or in court that said item is considered safe or wait for health canada to either ease or lift the ban on their own or by govt mandate or they can highly regulate items making them unaffordable or not cost effective crossing the border.
look at what the fda can have power over in the states as they might ban
vaping products in the u.s. or be highly regulated.