Based on world production of fibers in 1999, about 54.5% was synthetic (of which 60.3% was polyester), 42.9% was plant fiber (of which 78.5% was cotton), and 2.6% was wool (Karus 2000). In addition to cotton, flax is the only other significant plant fiber crop grown in temperate regions of the world (kenaf has received some enthusiastic backing in the southern US in recent years, but is most cheaply produced in India, Bangladesh, and China). Flax held 2.7% of the world plant fiber market in 1999, while hemp had only 0.3% (Karus 2000). Hemp fiber can potentially replace other biological fibers in many applications, but also, as noted below, can sometimes compete with minerals such as glass fiber and steel. As forests diminish, cultivation of annual plants as fiber sources is likely to increase. While crop residues like cereal straw will probably supply much of the need, specialty fiber plants such as hemp also have potential. The four conditions that will need to be met are (after Bolton 1995): (1) the material should be produced at a large enough scale; (2) the price should be low enough; (3) the fiber characteristics should be adequate for the end use; and (4) proven technology should be available for the processing of the new raw material. Of these criteria only point 3 is adequately met at this time for hemp in North America, but this is to be expected in a crop that has only begun to be cultivated after an absence of many years.
According to DSM-V criteria, 9% of those who are exposed to cannabis develop cannabis use disorder, compared to 20% for cocaine, 23% for alcohol and 68% for nicotine. Cannabis abuse disorder in the DSM-V involves a combination of DSM-IV criteria for cannabis abuse and dependence, plus the addition of craving, minus the criterion related to legal troubles.[110]
Strasser F, Luftner D, Possinger K, et al.: Comparison of orally administered cannabis extract and delta-9-tetrahydrocannabinol in treating patients with cancer-related anorexia-cachexia syndrome: a multicenter, phase III, randomized, double-blind, placebo-controlled clinical trial from the Cannabis-In-Cachexia-Study-Group. J Clin Oncol 24 (21): 3394-400, 2006. [PUBMED Abstract]
Marijuana is the most common illegal drug reported in motor vehicle accidents.[75] A 2012 meta-analysis found that cannabis use was associated with an increased risk of being involved in a motor vehicle crash.[76] A 2016 review also found a statistically significant increase in crash risk associated with marijuana use, but noted that this risk was "of low to medium magnitude."[77] The increase in risk of motor vehicle crash for cannabis use is between 2 and 3 times relative to baseline, whereas that for comparable doses of alcohol is between 6 and 15 times.[78]

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.[52] A reduced quality of life is associated with heavy cannabis use, although the relationship is inconsistent and weaker than for tobacco and other substances.[53] It is unclear, however, if the relationship is cause and effect.[53]


Some jurisdictions use free voluntary treatment programs and/or mandatory treatment programs for frequent known users. Simple possession can carry long prison terms in some countries, particularly in East Asia, where the sale of cannabis may lead to a sentence of life in prison or even execution. Political parties, non-profit organizations, and causes based on the legalization of medical cannabis and/or legalizing the plant entirely (with some restrictions) have emerged in such countries as China and Thailand.[213][214]

Cannabis can be prepared into various foods generally called ‘edibles’. It takes between 1-3 hours to feel the effects after eating cannabis.2 Impatient or naïve users may believe they have not taken enough to feel the effects, and if they consume more they may find later that the psychoactive effects are unpleasantly strong. When edible products have inconsistent levels of THC even experienced users may find it difficult to regulate the amount consumed.
Some jurisdictions use free voluntary treatment programs and/or mandatory treatment programs for frequent known users. Simple possession can carry long prison terms in some countries, particularly in East Asia, where the sale of cannabis may lead to a sentence of life in prison or even execution. Political parties, non-profit organizations, and causes based on the legalization of medical cannabis and/or legalizing the plant entirely (with some restrictions) have emerged in such countries as China and Thailand.[213][214]
Smoking cannabis can have an immediate effect. It can take an hour or more to feel the effects when eaten. Cannabis can make you feel relaxed, giggly, and hungry, or hallucinate or have a dry mouth. Using more cannabis can result in negative effects including blurred vision, bloodshot eyes, feeling sluggish, difficulty concentrating, slower reflexes, increased heart rate and lower blood pressure, and feelings of paranoia and anxiety.

Animal studies have suggested a synergistic analgesic effect when cannabinoids are combined with opioids. The results from one pharmacokinetic interaction study have been reported. In this study, 21 patients with chronic pain were administered vaporized Cannabis along with sustained-release morphine or oxycodone for 5 days.[57] The patients who received vaporized Cannabis and sustained-release morphine had a statistically significant decrease in their mean pain score over the 5-day period; those who received vaporized Cannabis and oxycodone did not. These findings should be verified by further studies before recommendations favoring such an approach are warranted in general clinical practice.
A CNN program that featured Charlotte's Web cannabis in 2013 brought increased attention to the use of CBD in the treatment of seizure disorders.[68][69] Since then, 16 states have passed laws to allow the use of CBD products with a doctor's recommendation (instead of a prescription) for treatment of certain medical conditions.[70] This is in addition to the 30 states that have passed comprehensive medical cannabis laws, which allow for the use of cannabis products with no restrictions on THC content.[70] Of these 30 states, eight have legalized the use and sale of cannabis products without requirement for a doctor's recommendation.[70]
France is Europe's biggest producer (and the world's second largest producer) with 8,000 hectares cultivated.[80] 70-80% of the hemp fibre produced in 2003 was used for specialty pulp for cigarette papers and technical applications. About 15% was used in the automotive sector, and 5-6% was used for insulation mats. About 95% of hurds were used as animal bedding, while almost 5% was used in the building sector.[14] In 2010/2011, a total of 11,000 hectares (27,000 acres) was cultivated with hemp in the EU, a decline compared with previous year.[68][81]

The importation and movement of hemp seeds and plants is restricted under federal law. According to the Statement of Principles on Industrial Hemp (81 Federal Register (FR) 53395) issued by the U.S. Department of Agriculture, U.S. Drug Enforcement Administration, and U.S. Food and Drug Administration, "industrial hemp plants and seeds may not be transported across State lines." For more information, contact the U.S. Drug Enforcement Administration.
But recent activity in Washington has legislators in every aisle waving banners for hemp. So far, 20 states have stepped up to encourage industrial hemp production.5 On February 7, 2014, the 2013 Farm Bill6 was signed into law, legitimizing industrial hemp as distinct, and authorizing university and State departments of agriculture (where it’s legal) for research or pilot programs. On January 8, 2015, The Industrial Hemp Farming Act of 2015, S. 134, was introduced in the U.S. Senate. 

Hemp has at times in the past been grown simply for its ornamental value. The short, strongly-branched cultivar ‘Panorama’ (Fig. 43) bred by Iván Bósca, the dean of the world’s living hemp breeders, was commercialized in Hungary in the 1980s, and has been said to be the only ornamental hemp cultivar available. It has had limited success, of course, because there are very few circumstances that permit private gardeners can grow Cannabis as an ornamental today. By contrast, beautiful ornamental cultivars of opium poppy are widely cultivated in home gardens across North America, despite their absolute illegality and the potentially draconian penalties that could be imposed. Doubtless in the unlikely event that it became possible, many would grow hemp as an ornamental.
A 100-gram portion of hulled hemp seeds supplies 586 calories. They contain 5% water, 5% carbohydrates, 49% total fat, and 31% protein. Hemp seeds are notable in providing 64% of the Daily Value (DV) of protein per 100-gram serving.[19] Hemp seeds are a rich source of dietary fiber (20% DV), B vitamins, and the dietary minerals manganese (362% DV), phosphorus (236% DV), magnesium (197% DV), zinc (104% DV), and iron (61% DV). About 73% of the energy in hempseed is in the form of fats and essential fatty acids,[19] mainly polyunsaturated fatty acids, linoleic, oleic, and alpha-linolenic acids.[20]
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