(marijuana) is the most commonly used drug, and consists of the dried leaves
and flowers of the Cannabis sativa plant. Due to environmental influences on plant growth
chemical potency varies (National Institutes on Drug Abuse
for Teens, 2017). Cannabis is a complex plant with over 400
chemical entities of which more than 60 of them are cannabinoid compounds, some
of them with opposing effects (Atakan, 2012). Most common among these
cannabinoids is THC (1-?-9-tetrahydrocannabinol), which is believed to be the primary
cannabinoid responsible for the psychoactive effects produced from consumption.
The primary differences between cannabis smoke and cigarette smoke are the
cannabinoids in marijuana and the nicotine in cigarette smoke. Nicotine is
known to be the addictive substance of cigarette smoking. With the illicit
nature of cannabis, less research has been undertaken on the constituents of
the smoke and on the respiratory effects of the inhalational of cannabis
(Bradford, 2017).

People in general smoke
cannabis cigarettes less often than tobacco cigarettes. Nevertheless the way
they inhale is very different. When smoking cannabis, people take in a puff
volume (the amount taken into the mouth) two-thirds larger than if they were
smoking tobacco. The inhaled volume (the amount that reaches the lungs) is
larger too (Henry et al. 2003). Cannabis smokers also hold the smoke in their
mouths four times longer, and end up with five times the amount of
carboxyhaemoglobin in their blood per cigarette smoked (Aldington et al. 2007).
This means it’s likely that the body retains much more of the products of
cannabis smoke, leading to a greater respiratory burden of carbon monoxide and
smoke particles than when smoking a similar quantity of tobacco. It’s estimated
that someone smoking a cannabis cigarette inhales four times more tar compared
with smoking a tobacco cigarette. They also retain one third more tar in the
respiratory tract (Hancox et al. 2010).

The use of cannabis
is now fixed within many societies, mostly used by the younger population and
widely perceived to be safe with regards to health. The potential for cannabis
to cause mental health problems has dominated the research completed around the
effects of the illicit drug, therefore the prospective of respiratory effects
have received relatively little attention (PT Reid, J Macleod, JR Robertson,
2010). Current evidence
shows that smoking cannabis is harmful to our lungs. We know far less about the
effects of cannabis smoke than the impact of tobacco smoke. However, there is
evidence that cannabis smoke causes many adverse effects, including: chronic
coughing, wheezing, sputum (phlegm) production, acute bronchitis, airway
obstruction and lung cancer (British Lung Foundation, 2012). Studies on cannabis are challenging and are related
to the use of tobacco and other social factors, and while many of the studies
referred to in this assignment are weighed down by the natural difficulties
in undertaking the study of disease correlated to the effects of cannabis, there
is concern that habitual smoking of