By Lee Moran
Last updated at 5:24 PM on 25th October 2011
Marijuana is almost twice as cheap to buy in the west of America than on the East Coast, a new study has revealed.
Whether used for recreational or medicinal purposes, the drug appears subject to the same market pressures as any other product.
U.S. geography experts have revealed the cost of the drug - which sells nationwide for an average of $377.02 per ounce - can vary widely from state to state.
Customers in the western state of Oregon can pick up an ounce for just $256 - whereas those in Delaware, in the east, are paying almost twice as much - $450 - for the same quantity.
High and lows: The marijuana price map was created by charting the cost of sales in cities were more than 30 transactions have been recorded, with the cheapest in green and the more expensive in yellow
The fact the majority of plants are grown in California means that simple distribution costs make it more cheaper to buy there, and more expensive to buy on the East Coast.
The higher percentage of young people, the ability to buy the substance for medicinal use and the subsequent difficulty police have in confiscating the drug in the west of the U.S. also contribute to its relative affordability.
The research by the Floating Sheep collective comes in the same month that a poll revealed 50 per cent of Americans would like marijuana to be legalised - despite its possession, sale, distribution and transportation remaining completely illegal under federal law.
And the evidence of widespread consumption also comes despite recent studies that show smoking the substance can trigger psychotic illness such as schizophrenia.
Research: The study comes in the same month that a poll revealed 50 per cent of Americans would like marijuana to be legalized
Ups and downs: Marijuana in Portland, Oregon (left) is almost half the price in Wilmington, Delaware (right)
Researchers analysed the price of 16,502 marijuana transactions in 2,397 U.S. cities - submitted by customers to the website priceofweed.com. Marijuana purchasers were also encouraged to say the quality of their purchase.
Research shows smoking marijuana can trigger psychotic illness such as schizophrenia almost three years earlier.
Eighty three studies involving 22,000 people were analysed.
It found people vulnerable to mental health problems were likely to suffer symptoms at a much younger age by using the drug.
The findings confirmed that it accelerates the onset of full-blown mental illness, which makes it harder to treat successfully.
Dr Matthew Large and colleagues at the Prince of Wales Hospital, New South Wales, claimed ‘overwhelming evidence’ showed it triggered schizophrenia and other psychotic disorders.
This was perhaps through an interaction between genetic and environmental disorders or by disrupting brain development.
They found that marijuana is cheapest in Northern California and the Pacific Northwest, the Four Corners region and a swath of the Great Plains, Illinois, Indiana, Northern Kentucky, and South Florida.
It is most expensive in the north-east, much of the Old Confederacy, and especially in Minnesota, Wisconsin, northern Michigan and Illinois.
Other factors influencing the price were the number of arrests for marijuana possession in an area and the general attitudes toward marijuana use in the population.
Richard Florida, Director of the Martin Prosperity Institute at the University of Toronto’s Rotman School of Management, said: ‘Their main finding is that marijuana prices rise the further a location is from the major centre of production.
‘Decreased supply leads to a rise in transportation costs and risk.
‘Clearly prices are as low as they are in the Pacific Northwest and Florida for the same reasons that potatoes are cheap in Idaho and corn is cheap in Iowa - because they’re close to the source, the places where the product is either grown, imported, processed, or all three.
‘Marijuana prices are lower in states with medical marijuana programs because the supply is higher and also because some of the demand is being met legally. The effect of enforcement is harder to ascertain.’
Mr Florida, alongside institute colleage Charlotta Mellander, also analysed other socio-economic and demographic factors that could affect the prices.
They found that the price is also higher where the majority share of voters say they are Republicans, where there are high levels of illegal drug use and where there is a higher percentage of African-Americans.
Earlier this month a Gallup poll revealed 50 per cent of Americans wanted marijuana to be legalised.
Supply and demand: The fact the majority of plants are grown in California means that simple distribution costs make it more cheaper to buy there, and more expensive to buy on the East Coast
Gaining steady support, the number was up from 46 per cent last year and had climbed from 12 per cent since 1969, when the research firm first asked the question.
The findings come months after the Obama administration toughened its stand on medical marijuana in the 16 states where it is legal for people with doctors’ recommendations.
The cheapest ounce of marijuana is on sale in Oregon - for $256
Delaware is the most expensive source of marijuana - at $450 per ounce
Nationwide the average price per ounce is:
High quality - $377.02
Mid-quality - $245.14
Low-quality - $138.12
The data was based on telephone interviews conducted over three days on a random sample of 1,005 U.S. adults, aged 18 and older.
The results showed more young people support legalising the drug than their elders, with those 18 to 29 showing a 62 per cent approval rating, compared to only 31 per cent for those 65 and older. More men than women support reform, at 55 to 46 per cent, relatively.
Those in the West (55 per cent) and Midwest (54 per cent) were more likely to favour it than those in the South (44 per cent).
Liberals were twice as likely as conservatives to favour legalizing marijuana, with relative 69 and 34 per cent approval ratings.
And Democrats and independents, both at 57 per cent, are more likely to be in favour than are Republicans, 35 per cent of which support the legalisation of marijuana.
Possession, sale, distribution and transportation of marijuana, medical or otherwise, remain completely illegal under federal law.
Under the U.S. Controlled Substances Act (CSA), marijuana is currently classified as a Schedule I drug, meaning that it has no accepted medical use.
The advocacy group National Organization for the Reform of Marijuana Laws previously claimed that marijuana is the third-most-popular recreational drug in America, behind only alcohol and tobacco.
The National Survey on Drug Use and Health in 2009 found that ‘16.7 million Americans aged 12 or older used marijuana at least once in the month prior to being surveyed, an increase over the rates reported in all years between 2002 and 2008.’
Gallup previously issued a survey last year which found that 70 per cent favoured making it legal for doctors to prescribe marijuana in order to reduce pain and suffering.
Reforming views: A graph shows a steady rise in support for the legalisation of marijuana, and steady decline in opposition over recent years, according to Gallup