Health effects of tobacco
The health
effects of smoking are the circumstances, mechanisms, and factors of
tobacco consumption on human health. Epidemiological research has been
focused primarily on cigarette tobacco smoking, which has been studied more
extensively than any other form of consumption
Tobacco is the single greatest
cause of preventable death globally. Tobacco use leads most commonly to
diseases affecting the heart, liver and lungs, with smoking being a major risk
factor for heart attacks, strokes, chronic obstructive pulmonary
disease (COPD) (including emphysema and chronic bronchitis), and cancer
(particularly lung cancer, cancers
of the larynx and mouth, and pancreatic
cancer). It also causes peripheral vascular disease and hypertension.
The effects depend on the number of years that a person smokes and on how much
the person smokes. Starting smoking earlier in life and smoking cigarettes
higher in tar increases the risk of these diseases.
Also, environmental tobacco smoke, or secondhand smoke, has been shown to cause
adverse health effects in people of all ages. Cigarettes sold in underdeveloped countries tend to have higher
tar content, and are less likely to be filtered, potentially increasing
vulnerability to tobacco-related disease in these regions.
The World Health Organization (WHO) estimates
that tobacco caused 5.4 million deaths in 2004 and 100 million deaths over the
course of the 20th century. Similarly, the United States Centers for Disease Control
and Prevention describes tobacco use as "the single most important
preventable risk to human health in developed countries and an important cause
of premature death worldwide." Several
countries have taken measures to control the consumption of tobacco
with usage and sales restrictions as well as warning messages printed on
packaging.
Smoke contains several carcinogenic
pyrolytic products that bind to DNA and cause many genetic mutations. There are 45 known or suspected chemical carcinogens
in cigarette smoke. Tobacco also contains nicotine, which is a
highly addictive psychoactive drug.
When tobacco is smoked, nicotine causes physical and psychological dependency.
Tobacco use is a significant factor in miscarriages among pregnant smokers, and
it contributes to a number of other threats to the health of the fetus such as
premature births and low birth weight and increases by 1.4 to 3 times the
chance for Sudden Infant Death Syndrome (SIDS).
The result of scientific studies done in neonatal rats seems to indicate that
exposure to cigarette smoke in the womb may reduce the fetal brain's ability to
recognize hypoxic conditions, thus increasing the chance of
accidental asphyxiation.
Incidence of impotence is approximately 85 percent higher
in male smokers compared to non-smokers, and is a key factor causing erectile dysfunction (ED)
Infinitive
·
Several
countries have taken measures to control the consumption of tobacco
Explain
Using
to infinitive because there is word
“Measures” before control which is indicate that control must have using to
infinitive instead of gerund.
Indefinite adjectives
· Smoke contains several carcinogenic pyrolytic products
that bind to DNA and cause many genetic mutations.
Explain :
- The indefinite adjective many modifies the noun genetic mutation
·
unlike demonstrative adjective, which indicate specific items,
indefinite adjectives do not point out specific things. they are formed from
indefinite pronouns. The most common indefinite adjective are no, any. many, few, several
www.grammar-monster.com/lessons/adjectives.htm
Using commas between
conjunction and clause
·
The health effects of
smoking are the circumstances, mechanisms, and factors of tobacco consumption on human health. (and)
Explain :
·
Use commas to separate independent clauses when they are joined by
any of these seven coordinating conjunctions: and, but, for, or, nor, so, yet
Use a pair of commas in the middle of
a sentence to set off clauses, phrases, and words that are not essential to the
meaning of the sentence. Use one comma before to indicate the beginning of the
pause and one at the end to indicate the end of the pause
http://en.wikipedia.org/wiki/Health_effects_of_tobacco
