Cannabis was criminalized in various countries beginning in the 19th century. The British colonies of Mauritius banned cannabis in 1840 over concerns on its effect on Indian indentured workers; the same occurred in British Singapore in 1870. In the United States, the first restrictions on sale of cannabis came in 1906 (in District of Columbia). It was outlawed in Jamaica (then a British colony) in 1913, in South Africa in 1922, and in the United Kingdom and New Zealand in the 1920s. Canada criminalized cannabis in The Opium and Narcotic Drug Act, 1923, before any reports of the use of the drug in Canada, but eventually legalized its consumption for recreational and medicinal purposes in 2018.
In the Australian states of Tasmania, Victoria, Queensland, and most recently, New South Wales, the state governments have issued licences to grow hemp for industrial use. The first to initiate modern research into the potential of cannabis was the state of Tasmania, which pioneered the licensing of hemp during the early 1990s. The state of Victoria was an early adopter in 1998, and has reissued the regulation in 2008.
Side effects of CBD include sleepiness, decreased appetite, diarrhea, fatigue, malaise, weakness, sleeping problems, and others. It does not have intoxicating effects like those caused by THC, and may have an opposing effect on disordered thinking and anxiety produced by THC. CBD has been found to interact with a variety of different biological targets, including cannabinoid receptors and other neurotransmitter receptors. The mechanism of action of CBD in terms of its psychoactive and therapeutic effects is not fully clear.
Tia has been Live Science's associate editor since 2017. Prior to that, Tia was a senior writer for the site, covering physics, archaeology and all things strange. Tia's work has appeared in Scientific American, Wired.com, and the Milwaukee Journal Sentinel. Tia grew up in Texas and has an undergraduate degree in mechanical engineering from the University of Texas at Austin, a master's degree in bioengineering from the University of Washington and a graduate certificate in science writing from the University of California Santa Cruz. When she's not editing stories, Tia enjoys reading dystopian fiction and hiking.
Cannabis has an ancient history of ritual use and is found in pharmacological cults around the world. Hemp seeds discovered by archaeologists at Pazyryk suggest early ceremonial practices like eating by the Scythians occurred during the 5th to 2nd century BC, confirming previous historical reports by Herodotus. It was used by Muslims in various Sufi orders as early as the Mamluk period, for example by the Qalandars. Smoking pipes uncovered in Ethiopia and carbon-dated to around c. AD 1320 were found to have traces of cannabis.
In May of 2018, Mount Vernon planted an industrial cultivar of hemp on the four-acre Pioneer Farm site. Under the 2015 Industrial Hemp Law enacted by the Virginia General Assembly and working with the industrial hemp research program of the University of Virginia, Mount Vernon planted hemp to expand its interpretation of George Washington’s role as an enterprising farmer. As the first historic home of the founding fathers to plant hemp, Mount Vernon will use the plant as an interpretative tool to help better tell the story of Washington’s role as a farmer.
Some users may experience an episode of acute psychosis, which usually abates after six hours, but in rare instances, heavy users may find the symptoms continuing for many days. A reduced quality of life is associated with heavy cannabis use, although the relationship is inconsistent and weaker than for tobacco and other substances. It is unclear, however, if the relationship is cause and effect.
In recent decades, the neurobiology of cannabinoids has been analyzed.[12-15] The first cannabinoid receptor, CB1, was identified in the brain in 1988. A second cannabinoid receptor, CB2, was identified in 1993. The highest expression of CB2 receptors is located on B lymphocytes and natural killer cells, suggesting a possible role in immunity. Endogenous cannabinoids (endocannabinoids) have been identified and appear to have a role in pain modulation, control of movement, feeding behavior, mood, bone growth, inflammation, neuroprotection, and memory.