by Tyrone Jack

All scientific indicators point to the use of marijuana having adverse health, safety, social, academic, economic, and behavioural consequences. Astonishingly, many people still view the substance as harmless. There is widespread and media advocacy for marijuana legalization or being decimalized for personal use. Policy makers, however, need to be more calculating and responsible. The public health concerns are far more critical in small developing countries without the means to properly finance cancer treatment facilities and to purchase the necessary drugs.{{more}} The Ministry of Health, the Ministry Economic Development, parents, teachers and churches need to buckle down on the message that “marijuana is not harmless.”

Marijuana became popular in St Vincent among youth population in the 1970s. Several users back then are now parents and grandparents of teenagers. They may have smoked marijuana without recognizing any of its adverse effects over the years, and they may now erroneously believe there is no harm in its use. A few points need to be made here:

1) Most of the marijuana available today is considerably more potent than yesterday’s “weed”.

2) Today, marijuana users tend to be younger than those of past generations.

3) We should be aware that genetically, environmentally and socially individuals are different and the adverse effect of any drug would manifest itself differently; this would be dependent on all the predisposing factors, including age, dose or concentration, and the rate of metabolism etc.

4) When societies reconsider the legal status of marijuana, policy makers and clinicians require sound knowledge of the acute and chronic effects of this psychoactive substance. Close attention needs to be paid to the ODDs Ratio (OR)

Odds Ratio (OR) defined:

Odds Ratio: is a measure of association between an exposure and an outcome. The OR represents the probability that an outcome will occur given a particular exposure. The Odds Ratio can also be used to determine whether a particular exposure is a risk factor for a particular outcome, and to compare the magnitude of various risk factors for that outcome. For example, an OR of four for a particular type of cancer, following exposure to a toxic chemical, is saying that you are four times more likely to get the cancer than those who were not exposed, or that you have an 80 per cent chance of coming down with the disease during your lifetime. Like in a horse race the ODD is not a predictor of certainty, but it gives a very good idea of which horse you should bet on to winning that race. The stronger the ODD, the more likely the event will happen. Since one is not likely to bet much of one’s hard earn money against a horse with an 80 per cent chance of winning a race, one should not gamble with his or her health or that of the nation and its wellbeing when the OR would be increasingly stacked against you. Taking measures that will increase the use of marijuana cannot be our safest bet.

• My first charge today against “Marijuana” is its danger to lung health.

The thoracic societies of Australia and New Zealand and the British Lung Foundation have issued major statements in recent years acknowledging the known harmful effect of cannabis on the lung. According to a report in 2012 from the British Lung Foundation’s the risk of lung cancer is actually 20 times higher from a cannabis cigarette than a tobacco cigarette. Part of the reason for this is that people smoking marijuana take deeper puffs and hold them for longer than tobacco smokers. This means that a person smoking a cannabis cigarette inhales four times as much tar and five times as much carbon monoxide as someone smoking a tobacco cigarette.

Cannabis smoke stimulates inflammation in the airway, so that the long-term use is associated with the development of bronchitis. The hydrocarbons found in marijuana smoke are 50-70 per cent more carcinogenic than tobacco smoke and an irritant to the lungs. The respiratory conditions common in tobacco smokers, such as daily cough, mucus production and risk of lung infections, are also found in marijuana smokers. Marijuana smoking is associated with impaired function of the immune system components in the lungs.

On September 11, 2009, the California Environ­mental Protection Agency, Office of Environmental Health Hazard Assess­ment, published the latest list of chemicals known to the state to cause cancer or reproductive toxicity. The list included a new chemical, marijuana smoke!

Researchers in Canada reported that “marijuana smoke contains significantly higher levels of toxic compounds — including ammonia and hydrogen cyanide — than tobacco smoke and may therefore pose similar health risks.” “Ammonia levels were 20 times higher in the marijuana smoke than in the tobacco smoke, while hydrogen cyanide, nitric oxide and certain aromatic amines occurred at levels 3-5 times higher in the marijuana smoke.” And according to researchers from the French National Consumers’ Institute, smoking three cannabis joints will cause you to inhale the same amount of toxic chemicals as a whole pack of cigarettes. Cannabis smoke contains seven times more tar and carbon monoxide than cigarette smoke. It is noteworthy that the tar phase of marijuana smoke contains many of the same carcinogenic compounds contained in tobacco smoke, including polycyclic aromatic hydrocarbons, such as benz[a]pyrene, which was identified as a key factor promoting human lung cancer.

A study from Monash University and the Alfred Hospital in Australia has found that “bullous lung disease occurs in marijuana smokers 20 years earlier than tobacco smokers. Often caused by exposure to toxic chemicals or long-term exposure to tobacco smoke, bullae are condition where air pockets trapped in the lungs causes obstruction to breathing and eventual destruction of the lungs.” Dr Matthew Naughton explains that “marijuana is inhaled as extremely hot fumes at the peak inspiration and held for as long as possible before slow exhalation. This predisposes to greater damage to the lungs and makes marijuana smokers more prone to bullous disease as compared to cigarette smokers.” I will add here that marijuana cigarette producers do not add filters.

Marijuana worsens breathing problems in patient with chronic obstructive pulmonary disease (COPD), according to a study released by the American Thoracic Society in May 2007. Among people age 40 and older, smoking cigarettes and marijuana together boosted the odds of developing COPD to 3.5 times the risk of someone who smoked neither.

Smoking “Marijuana” Can Cause Cancers

The ODDs Ratio for marijuana induced cancers at different sites in the body

Lung Cancer: In a Tunisian study positive odds ratios were found for lung cancer. For men who had smoked less than one cannabis cigarette per day or one or more cigarettes per day, compared with those who never smoked were 4.0 and 4.2, respectively. The odds ratios for lung cancer for smokers who had smoked cannabis cigarettes for <5 years or 5 years were 4.7 and 3.4 respectively, when compared with the never smokers group. Head and Neck: Zuo-Feng Zhang et al looked at ‘Marijuana Use and Increased Cancer Risk of the Head and Neck’ and found that marijuana use may increase the risk of head and neck cancer with a strong dose-response pattern. After controlling for age, sex, race, education, alcohol consumption, pack-years of cigarette smoking, and passive smoking, the risk of cancer of the head and neck was increased with marijuana use. The odds ratio being 2.6, dose-response relationships were observed for frequency of marijuana use and days and years of marijuana use. These associations were stronger for subjects who were 55 years of age and younger, OR, 3.1. Prostate: Victoria Cortessis, MSPH, PhD, assistant professor of preventive medicine at the Keck School of Medicine of USC in Los Angeles, and her colleagues found that men with a history of using marijuana were twice as likely to have the subtypes of cancer of the testicles called ‘non-seminoma’ and mixed germ cell tumours. ‘Non-seminoma’ is one of the most aggressive and deadly cancers, it is diagnosed early, between 25 and 35 years with a lower than five-year survival rate. Marijuana associated with cancer of the testes is at OR =1.7, the brain OR =2.8 and the throat OR =1.7. Another study published by the Medical College of Georgia and Stanford University suggests a causal relationship between marijuana exposure and bladder cancer. Yes, several factors may affect the reliability of the ODD ratio; these include the sample size, confounding exposures and or comorbid conditions. It is important that when we read articles or “so-called studies” that these potential biases are looked at or explained. A few years ago, one research group looked at Internet papers on marijuana and found 14,065. However, when the terms “toxicity” “complications” and “mechanism” were added, the list narrowed to just 5,198. So, when in your defence you seek to argue against what is written here, be aware that lot of what you read on the Internet “are not worth the paper they are written on”. Studies should be published in respectable scientific journals, as these would have undergone the necessary peer review evaluations.