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Effects Of Pot Essay, Research Paper

Effects Of Pot Marijuana has been used as a drug since the beginning oftime, yet there are still many mysteries about its healtheffects on humans. Marijuana, or cannabis sativa, is apreparation of the crushed flowers and buds of female hempplant. The existence of the plant has been reported asearly as 1500-1200 BC. in China, and cannabis has beendescribed as an analgesic as early as 200 AD . Since then, an overwhelming number of studies have attemptedto explain the physical and psychological effects ofcannabis on humans. Physical Effects Physically, cannabis is relatively harmless. Studieshave observed interesting results, including that it causesstructural changes in the brain, depresses male spermcounts, causes chromosome damage, lowers testosteronelevels, and damages the lungs. Most of these claims,however, have been unreplicated in humans or have beencontradicted by other work. This section will address eachof these reported negative side-effects. Various studies have claimed that cannabis destroys braincells. However, several other studies found no structuralor neurochemical atrophy in the brain at all. Furthermore, itshould be noted that Heath’s work was sharply criticized foravoiding safeguards of bias and reporting “changes” thatoccur normally in the mammalian brain. Wu et al. found a correlation between cannabis useand low sperm counts in human males. This is misleadingbecause a decrease in sperm count has not been shown to havea negative effect on fertility and because the sperm countreturns to normal after cannabis use has stopped.. Another claim made was that cannabis causes chromosomebreakage. The primary source for this are studies that wereconducted by Dr. Gabriel Nahas in the early 1980s. Nahasobserved abnormalities in somatic (not sex) cells of rhesusmonkeys in vitro (i.e., in test tubes and petri dishes) andthen made the unjustified conclusion that these changeswould occur in human bodies in vivo (in the body). Nahas’work was criticized by his colleagues and, in 1983, hebacked away from his own conclusions. A widely held claim has also been that cannabis lowersmale testosterone levels. This theory hasbeen challenged by several studies that found nocorrelation at all. Marijuana and Health, also, afterreviewing literature at that time, concluded that “Due toconflicting and incomplete evidence, it is not possible toconclude at the present time whether marijuana smoking hasa significant effect upon gonadotropic and testosteroneconcentrations in humans.” The most serious physical danger of using cannabis is insmoking it. Inhaling any sort of burnt plant matter is notvery good for the lungs. Tashkin et al. reportsdecreased gas exchange capacity and the existence ofparticle residue in the lungs of marijuana smokers severaltimes greater than for tobacco smokers. Wu noted that marijuanais several times more carcinogenic than tobacco. These findings,though, must be interpreted with caution. In both studies,smoked marijuana was not filtered, while smoked tobacco was. Tashkin notes that, “these differences could largely account formore than twofold greater tar yield from marijuana than tobacco thatwas measured using syringe-simulated puffs of similar volumeand duration.” Smoking cannabis through a water-pipe willfilter out water soluble carcinogens and will also greatlycool down the smoke. Furthermore, cannabis need not besmoked: In Middle Eastern countries, it has been consumedthrough teas and food for centuries, avoiding thecarcinogenicity of smoke altogether. Despite cannabis’ known negative effects to lungfunction, it has never been reported to cause a singleinstance of lung cancer. Tobacco, though, is expected tokill 400,000 people this year. If cannabis isso much more dangerous to a user’s lungs than tobacco and isso much more carcinogenic, why aren’t there stacks ofreports of cannabis-induced lung cancer? One interestingtheory is that it’s because tobacco tars are significantlyradioactive, while marijuana tars aren’t at all. Wintersfound that a pack-and-a-half-a-day smoker oftobacco is exposed to 8000 mrem of radiation a year, equalto the dose of 300 chest x-rays. A more recent studyindicates that a pack-and-a-half-a-day smoker receives 16000mrem of radiation more than a non-smoker, annually. Itcould also be noted that the mere contents ofcarcinogenic chemicals doesn’t necessarily indicate anextreme health hazard. For example, roasted coffeecontains 800 volatile chemicals, of which only 21 have

been tested on rodents, and of those, 16 werecarcinogenic. Coffee has never been considereda great cancer-causing substance, though. Cannabis has also been known for its many therapeuticuses, including the treatment of open angle glaucoma,asthma, and the nausea associated with chemotherapy. It hasalso been described as a tumor retardant, an antibiotic, asleep-inducer, and a muscle relaxant. Psychological Effects The psychological effects of cannabis use have beendescribed quite many years before the physical effects, yetare as accurate today as they were 100 years ago. Followingis an early account of its intoxicating properties made byDr. John Bell in 1857: “I had taken the drug with great skepticism as to its reputed action, or at any rate with the opinion that it was grossly exaggerated, and I accordingly made up my mind not to be ‘caught napping’ in this way again, and to keep a careful watch over my thoughts. But while enforcing this resolution as I supposed, I found myself, to my own astonishment, waking from a reverie longer and more profound than any previous. From skepticism, to the fullest belief of all I had read on the subject, was but a step. Its effects so far surpassed anything which words can convey, that I began to think I was on the verge of narcotic poisoning; yet, strange to say, there was not the slightest feeling of inquietude on that account. I resolved to walk into the

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