A new study calculates British Columbians' pot purchases total about half a billion dollars each year, and the pro-legalization researchers conducting the study say that means the province could be bringing in massive tax revenues.

Researchers from the University of British Columbia and Simon Fraser University sought to quantify the retail value of marijuana sold on the black market.

They looked at the price of marijuana and research that suggests more than 366,000 people in B.C. use pot to estimate the pot industry is worth between $443 million and $564 million a year.

The researchers also point to data from Washington, which recently held a successful referendum to legalize pot, that suggests the same number of pot smokers in that state could bring in $2.5 billion in taxes over five years in a regulated system.

They say the revenues could be used to fund addictions programs and health care, similar to the new system set to be rolled out in Washington and Colorado, where the public recently voted to legalize the drug.

Lead author Dan Werb says regulation is tricky, but replacing drug pushers with the government would allow for more control over prices and who has access to the product.

Werb and the other researchers are members of the pro-pot Stop the Violence B.C. coalition, which advocates for changes to drug policies designed to take the business of marijuana away from violent organized crime groups and reduce overall use.