A Darwin Menzies School of Health study has revealed that up to 12 per cent of Arnhem Land residents are spending about two-thirds of their income on cannabis.

Researcher Alan Clough says people on remote communities often pay much more for marijuana than elsewhere in the Territory.

He says the marijuana is grown outside the community and brought in by local dealers.

"There seems to be a more or less standard size of plastic packets into which you can stuff varying amounts of material and the standard price of that package seems to be $50," he said.

"As a dealer, you would have a lot of flexibility in charging what the market will bear."

"Probably about 70 per cent of the continuing cannabis users would spend about 30 per cent of their weekly income, and then the impact on the total community's financial resources are estimated to be somewhere between six and 10 per cent of the total monetary resources in the community.