Colorado Marijuana Sales Become Legal Police in Colorado have increased patrols around marijuana retailers as the the state allows the first sales for recreational use in the US. Shops were planning celebrations and hiring extra security to prepare for potential crowds and some customers were camping out overnight to buy up to an ounce (28.3 grammes) of legal weed. Possession, cultivation and private personal consumption of marijuana by adults has been legal in Colorado for more than a year, but so-called Green Wednesday is a major milestone for the legalisation movement. "No one's ever done this before," said Robin Hackett, manager of the pot shop Botana Care, who planned to have a DJ to greet shoppers. Inside a warehouse in a Denver suburb, three workers for Botana Care have been rolling hundreds of marijuana cigarettes. "We expect to have 2,000 joints ready to go by the time we open on January 1," Mr Hackett said. Marijuana cigarettes are prepared for sale Colorado has set up an elaborate plant-tracking system to try to keep the drug off from the black market, and regulators set up packaging, labelling and testing requirements, along with potency limits for edible pot. Denver International Airport has installed signs warning visitors they cannot legally take their marijuana out of the state. "We understand that Colorado is under a microscope," Jack Finlaw, lawyer to Governor John Hickenlooper and overseer of a task force to chart new pot laws, recently told reporters. But critics fear that legalising recreational sales of marijuana could bring serious public health problems. "This movement in public policy basically conflicts with the essence of bringing greater mental health and public health," said Patrick Kennedy, a former congressman and chairman of Smart Approaches to Marijuana, which opposes legalisation. Possession, cultivation and private consumption were already legal Along with Washington state, Colorado legalised possession and use of small amounts of cannabis by adults for non-medical purposes under a statewide ballot measure approved by voters in November 2012. State authorities project wholesale and retail sales of cannabis products will total $578m in annual revenues, which will generate $67m in sales tax receipts for the state, once the system is fully operational.