Effects Of Pot Essay, Research Paper

The Health Effects of Marijuana on Humans

Tim Murphy

Introduction

Marijuana has been used as a drug since the beginning of

time, yet there are still many mysteries about its health

effects on humans. Marijuana, or cannabis sativa, is a

preparation of the crushed flowers and buds of female hemp

plant. The existence of the plant has been reported as

early as 1500-1200 BC. in China, and cannabis has been

described as an analgesic as early as 200 AD .

Since then, an overwhelming number of studies have attempted

to explain the physical and psychological effects of

cannabis on humans.

Physical Effects

Physically, cannabis is relatively harmless. Studies

have observed interesting results, including that it causes

structural changes in the brain, depresses male sperm

counts, causes chromosome damage, lowers testosterone

levels, and damages the lungs. Most of these claims,

however, have been unreplicated in humans or have been

contradicted by other work. This section will address each

of these reported negative side-effects.

Various studies have claimed that cannabis destroys brain

cells. However, several other studies found no structural

or neurochemical atrophy in the brain at all. Furthermore, it

should be noted that Heath’s work was sharply criticized for

avoiding safeguards of bias and reporting “changes” that

occur normally in the mammalian brain.

Wu et al. found a correlation between cannabis use

and low sperm counts in human males. This is misleading

because a decrease in sperm count has not been shown to have

a negative effect on fertility and because the sperm count

returns to normal after cannabis use has stopped..

Another claim made was that cannabis causes chromosome

breakage. The primary source for this are studies that were

conducted by Dr. Gabriel Nahas in the early 1980s. Nahas

observed abnormalities in somatic (not sex) cells of rhesus

monkeys in vitro (i.e., in test tubes and petri dishes) and

then made the unjustified conclusion that these changes

would occur in human bodies in vivo (in the body). Nahas’

work was criticized by his colleagues and, in 1983, he

backed away from his own conclusions.

A widely held claim has also been that cannabis lowers

male testosterone levels. This theory has

been challenged by several studies that found no

correlation at all. Marijuana and Health, also, after

reviewing literature at that time, concluded that “Due to

conflicting and incomplete evidence, it is not possible to

conclude at the present time whether marijuana smoking has

a significant effect upon gonadotropic and testosterone

concentrations in humans.”

The most serious physical danger of using cannabis is in

smoking it. Inhaling any sort of burnt plant matter is not

very good for the lungs. Tashkin et al. reports

decreased gas exchange capacity and the existence of

particle residue in the lungs of marijuana smokers several

times greater than for tobacco smokers. Wu noted that marijuana

is 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 for

more than twofold greater tar yield from marijuana than tobacco that

was measured using syringe-simulated puffs of similar volume

and duration.” Smoking cannabis through a water-pipe will

filter out water soluble carcinogens and will also greatly

cool down the smoke. Furthermore, cannabis need not be

smoked: In Middle Eastern countries, it has been consumed

through teas and food for centuries, avoiding the

carcinogenicity of smoke altogether.

Despite cannabis’ known negative effects to lung

function, it has never been reported to cause a single

instance of lung cancer. Tobacco, though, is expected to

kill 400,000 people this year. If cannabis is

so much more dangerous to a user’s lungs than tobacco and is

so much more carcinogenic, why aren’t there stacks of

reports of cannabis-induced lung cancer? One interesting

theory is that it’s because tobacco tars are significantly

radioactive, while marijuana tars aren’t at all. Winters

found that a pack-and-a-half-a-day smoker of

tobacco is exposed to 8000 mrem of radiation a year, equal

to the dose of 300 chest x-rays. A more recent study

indicates that a pack-and-a-half-a-day smoker receives 16000

mrem of radiation more than a non-smoker, annually. It

could also be noted that the mere contents of

carcinogenic chemicals doesn’t necessarily indicate an

extreme health hazard. For example, roasted coffee

contains 800 volatile chemicals, of which only 21 have

been tested on rodents, and of those, 16 were

carcinogenic. Coffee has never been considered

a great cancer-causing substance, though.

Cannabis has also been known for its many therapeutic

uses, including the treatment of open angle glaucoma,

asthma, and the nausea associated with chemotherapy. It has

also been described as a tumor retardant, an antibiotic, a

sleep-inducer, and a muscle relaxant.

Psychological Effects

The psychological effects of cannabis use have been

described quite many years before the physical effects, yet

are as accurate today as they were 100 years ago. Following

is an early account of its intoxicating properties made by

Dr. 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 street. While rising

from the chair, another lucid interval showed that

another dream had come and gone. While passing

through the door, I was aware of having wandered

again, but how or when I had permitted myself to

fall into the reverie I was perfectly unconscious,

and knew only that it seemed to have lasted an

interminable length of time.”

The user of cannabis feels the onset of the “high”

between 7 seconds (when smoking) and up to 30 minutes (after

eating). This involves a relaxed and peaceful, yet

sometimes euphoric state of mind. At high doses, it can

cause hallucinations. The effects last from 2 to 4 hours

after the drug is ingested, and it usually leaves the user

in a relaxed state for several hours after the high. One of

the main intoxicating properties is that short term memory

is inhibited for the duration of the high. Thoughts may

seem unclear, and it might be difficult for a user to

concentrate on logical-complicated concepts like

mathematics.

Long-term effects have been argued for many years. There

are claims of an “amotivational syndrome” where users are

said to withdraw from society and lose ambition. In

reviewing evidence for and against the theory of this

“syndrome,” however, Marijuana and Health concluded that:

“Such symptoms have been known to occur in the

absence of marijuana. Even if there is an

association between this syndrome and the use of

marijuana, that does not prove that marijuana

causes the syndrome. Many troubled individuals

seek an ‘escape’ into use of drugs; thus, frequent

use of marijuana may become one more in a series

of counterproductive behaviors for these unhappy

people.”

Other studies have found another interesting correlation:

Shedler reported these results in a longitudinal survey

of adolescents:

“Adolescents who engaged in some drug

experimentation (primarily with marijuana) were

the best adjusted in the sample. Adolescents who

used drugs frequently were maladjusted, showing

distinct personality syndrome marked by

interpersonal alienation, poor impulse control,

and manifest emotional distress. Adolescents who,

by age 18, had never experimented with any drug

were relatively anxious, emotionally constricted,

and lacking in social skills.”

Among other findings, Utah Power and Light spent $215.00 per

year less on health insurance benefits for drug users than

on the control group, and employees who tested positive for

cannabis at Georgia Power Co. had a higher promotion rate

than the company average, and were absent 30 percent less

(Morris, 1991).

Conclusion

Whether cannabis use causes permanent physical or

psychological changes in its users is still under question.

The most serious concern is its effects on the pulmonary

system, yet, studies have often used poor controls (i.e., no

filtration) and their results can mislead an uncareful

reader. Smoking the drug with a different apparatus or

ingesting it without smoking at all could greatly effect the

results of these studies.

The acute psychological effects of cannabis that cause

its intoxicating properties are no mystery, as any user can

report. Long term effects of cannabis use could possibly

lead to the so-called “amotivational syndrome,” but

scientific evidence is lacking.

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