Uruguay's House of Representatives has passed a bill to legalize marijuana by 50 of the 96 MPs following 13 hours of tough debates. Now the bill is to be approved by the Senate to make Uruguay the first country to regulate the production, distribution and sale of marijuana. President Jose Mujica believes that the measure will remove profits from drug dealers and divert users from harder drugs. Martin Jelsma, the Coordinator of Drugs & Democracy program at Transnational Institute in Amsterdam, shared his thoughts on the new legislation with the Voice of Russia.

Long-term marijuana use is not associated with a raft of physical health problems, according to a new study. Researchers tracked the marijuana habits of 1,037 New Zealanders from birth to middle age to see what effect those habits have on physical health, including lung function, systemic inflammation, cholesterol levels, blood pressure, body weight, blood sugar and dental health. After controlling for other factors known to affect health, especially tobacco use and socioeconomic status, marijuana use had no negative effect on any measure of health, except for dental health. (See also: Study questions role for marijuana in teen users’ IQ decline)

Cases of substance-use disorders are exactly what the federal government is hoping to avoid in its push to legalize recreational marijuana, and they may be the biggest test of whether legalization is ultimately successful. They could also prove to be immensely challenging. That it’s even possible to become dependent on cannabis could come as a surprise to many, especially young people. A survey conducted by the Canadian Centre on Substance Abuse (CCSA), published last year, found that a majority of youth were unaware that cannabis can be addictive and lead to withdrawal symptoms. Marijuana use among young people has declined over the past few years, but Canada still has one of the highest rates in the developed world.

It's been a five years since Colorado's voters approved Constitutional Amendment 64, legalizing recreational marijuana in the state. Sales commenced four years ago this January. Although the amendment passed by a comfortable 10-point margin, the debate in Colorado has continued since prohibition ended, most recently flaring up with an editorial published in the Colorado Springs Gazette. The Gazette's editorial board referred to what has happened in Colorado as "an embarrassing cautionary tale," presenting a laundry list of the purported ill-effects of the change in the law. However, evidence from Colorado shows that marijuana legalization does not lead to increased teen usage, does not lead to increased homelessness, and does not lead to societal breakdown.

Two years after the sale of marijuana was legalized in Canada, and researchers have yet to see the feared increase in use, says Michael Boudreau, a criminology professor at St. Thomas University. About six per cent of Canadians report they consume cannabis on a daily basis, a number that's remained unchanged from before legalization. "So there, we're not seeing a skyrocket use of cannabis," said Boudreau. In fact, use of cannabis in the age bracket of 15 to 17 has been cut in half, down to 10 per cent from the 20 per cent it was before legalization. But cannabis consumption for those between the ages of 18 and 24 is 33 per cent, which Boudreau said is relatively unchanged. (See: ‘The kids are alright’: reflections on two years of legal cannabis in Canada)

Rates of adolescent marijuana use and abuse have declined across the US, according to a study that casts doubts on one of the central arguments against legalizing weed. Researchers from the Washington University School of Medicine in St Louis surveyed 216,852 teenagers from all 50 states and found that the number of adolescents with marijuana-related disorders dropped by 24% from 2002 to 2013. Overall teen pot use also decreased by 10%, despite the fact that more than a dozen states legalized medical marijuana and decriminalized the drug during that time. (See also: No, legal weed is not ‘dumbing down’ the nation’s teens)

The Organization of American States' (OAS) latest drug consumption report highlights shifting trends in drug use among youths in the Western Hemisphere. One noteworthy trend is changing cocaine consumption among high school students in South America, when compared to the United States -- the region's largest overall drug consumer. While cocaine use among US high school students has declined since peaking in 1998, consumption in South America has increased, most notably in Argentina and Uruguay, and less so in other nations like Chile and Brazil.

A 2012 Duke University study found that persistent, heavy marijuana use through adolescence and young adulthood was associated with declines in IQ. Other researchers have since criticized that study's methods. A follow-up study found that the original research failed to account for a number of confounding factors, such as cigarette and alcohol use, mental illness and socioeconomic status. Two new reports tackle the relationship between marijuana use and intelligence from two very different angles: One examines the life trajectories of 2,235 British teenagers between ages 8 and 16, and the other looks at the differences between American identical twin pairs in which one twin uses marijuana and the other does not.

The Beckley report, Licensing and Regulation of the Cannabis Market in England and Wales: Towards a Cost-Benefit Analysis, grasps of the economic consequences of a regulated market, as opposed to the current prohibitionist model. This is essential for evaluating the impacts of possible drug policy reform. The report outlines the factors which must be included in further cost-benefit analyses. The report costed 60.000 pounds and 3 years to create. Reliable data was often lacking and more evidence is needed.

One of the key advantages to a cost-benefit analysis is its complete elimination of subjective and emotive processes, which have become an unfortunate mainstay in the drug policy debate - this gives the results an objective credibility.

It is very important to note that by excluding 'internal costs and benefits' the report specifically excludes the reasons why people use cannabis, such as medication, enjoyment and creativity - instead this report takes the perspective of a concerned tax payer, or a budget-focused politician.

An often-used argument surrounding cannabis reform is the concept of the 'gateway effect'; the idea that cannabis use leads to the use of 'harder drugs'. This report not only rejects the idea of a demand side gateway effect (through a thorough assessment of the available data), but also introduces the idea that a regulated market would virtually eliminate another sort of damaging gateway effect, namely the supply-side gateway. This is where social dealers of cannabis come into contact with professional dealers of a larger variety of drugs and thus are more likely to progress to dealing harder drugs.

Another element which has gained much attention in recent history is the mental health costs of cannabis brought about by the increased ratio of THC to CBD. One of the many advantages of a regulated market is that through health-education, labelling and variable tax rates, strains of cannabis with a high CBD ratio can be encouraged, particularly for vulnerable users.

The main conclusion is that there would be a net social benefit to reform of some­where between 280 and 460 million pounds. This means that even when we ignore the experiential benefits claimed by cannabis users and just focus on the financial effects on society at large, the argument for reform remains robust, compelling and increasingly difficult for policy makers to ignore.

On top of the financial benefit there are of course many other advantages. These include increased respect of human rights, the avoidance of discrimination in the enforcement of prohibition, the minimisation of the blighting effect of a criminal record on a person’s life and the increased accessibility to health information and treatment. The current criminalization of cannabis users sacrifices the credibility of health campaigns. Moreover, based on US evidence it is expected that access to cannabis for teenagers would probably decrease.

Because taxes are a transfer, rather than a net social gain, they are not included in the report’s cost benefit analysis. However, a conservative estimation is made of what the tax revenue might be following reform.

The authors aim to bring the price of cannabis to lower than the illicit price, whilst aiming to keep it high enough to deter the expansion of use due to low price, particularly by the young. This would be achieved by a tax rate of around 70%, which is lower than the 83% on cigarettes and closer to the 72% on high alcohol beer.

The report predicts a small increase in cannabis quantity [+15% - +40%] due to a decreased cannabis price. The price elasticity of cannabis is estimated between [-0.2, -0.7]. The cross-price elasticity is important to consider: will alcohol consumption decrease if the price of cannabis decreases and cannabis consumption increases? According to a study of Clements and Zhao (2005), a4% increase in cannabis consumption would lead to a decrease of alcohol consumption (-1% beer, -2% wine, -4% spirits).

The authors assumed a cap on THC levels of 10% for licensed cannabis. By creating this limitation it leaves higher THC strains of cannabis in the illicit market. It would probably be better to keep all strains of cannabis within the licit market, and use taxation intelligently to make more potentially risky or harmful strains of cannabis less financially attractive. Campaigns could move users away from combining tobacco and cannabis.

The authors estimate that the government would gain in budgetary terms by something around one billion pounds a year, roughly three quarters of which would come from tax revenues rather than expenditure savings. In these times of economic hardship cost-benefit analyses with positive results should surely begin to play a key role in government.

The report

Mark Bryan, Emilia Del Bono, Stephen Pudney, Licensing and Regulation of the Cannabis Market in England and Wales: Towards a Cost-Benefit Analysis, Institute for Social and Economic Research (Iser), University of Essex & Beckley Foundation, September 2013

The proportion of young people using marijuana as their first drug doubled in the 10 years from 2004, a US-based study has found. The government study reveals that among people aged between 12 and 21, the proportion of those who tried cigarettes as their first drug fell from about 21% to just under 9% between 2004 and 2014. However, the proportion who turned first to marijuana almost doubled from 4.4% to 8%. While some studies have suggested that, overall, use and abuse of marijuana has fallen among teenagers in the US, the latest research sought to look at trends in which drug, if any, young people turned to first.

With the widespread availability of marijuana in recent years thanks to its legalization in a growing number of states, there has been increasing concern about the long-term health consequences on teens who might be able to get easier access to it illegally. A study published by the American Psychological Association in the journal Psychology of Addictive Behaviors should alleviate some of the worst fears. The researchers found no links to physical or mental health issues -- including depression, psychotic symptoms or asthma -- in any group, even those with very high use.

The Federal Commission for Addiction Issues said that cannabis use in Switzerland had not changed significantly in the past ten years. Despite its popularity, the percentage of problematic users is low, it said. The risks of cannabis are mainly linked to high amounts of THC [active ingredient], early use among teenagers, prolonged use, mixing cannabis and tobacco, and if it is used by people with existing mental problems. The commission recommends Switzerland legalise and regulate the market while protecting the health of its population, especially young people. The government is meanwhile is proposing limited pilot projects. (See also: Top Swiss health commission call for 'legalisation' of cannabis)

In 2016, rates of marijuana use among the nation's 12- to 17-year-olds dropped to their lowest level in more than two decades, according federal survey data. Last year, 6.5 percent of adolescents used marijuana on a monthly basis, according to the latest National Survey on Drug Use and Health. That represents a statistically significant drop from 2014, when the nation's first recreational marijuana shops opened in Washington state and Colorado. The last time monthly teen marijuana use was this low was 1994, according to the survey. The federal data show that adult marijuana use, on the other hand, is rising. (See also: Here's one marijuana trend you should actually be worried about)

Fewer young people are using marijuana now as compared to 2012, when the first states moved to legalize cannabis, according to a federally funded study. The 2018 Monitoring the Future survey found that annual, monthly and daily marijuana use remained lower among the nation’s 8th, 10th and 12th grade students compared to pre-legalization levels. Teens’ perceived availability of cannabis continued to decline in 2018 as well. Fewer adolescents are saying they perceive occasional or frequent cannabis use as harmful. Experts have long believed that lower perceptions of risk are correlated with more frequent use, but the data doesn’t seem to bear out those concerns. (See also: Teen marijuana use actually declined in Washington State after legalization, study finds)

As New Zealand prepares for a referendum on legalising recreational cannabis, surveys show opposite trends for cannabis use by adults and adolescents. Adult use of cannabis has risen sharply over the last few years, reflecting softening attitudes. But our study shows cannabis use in adolescents has been decreasing since 2001. It is important to understand what drives these trends to predict how legalisation could affect teen cannabis use. Our research shows the proportion of 14 to 15-year-olds reporting they had ever used cannabis fell from 19% in 2012 to 14% in 2018. Those who reported using in the past month fell from 10% to 8% over the same period. The recent changes are modest, but they follow substantial declines in cannabis use among high school students between 2001 and 2012.

Teenagers who use cannabis daily before the age of 17 are more than 60% less likely to complete high school or university, research published in Lancet Psychiatry found. The researchers called for their findings to be considered in cannabis legalisation reform. Alex Wodak of the Australian Drug Law Reform Foundation said the evidence for the harms of frequent use in the study was "compelling" but added daily use before age 17 would be "pretty uncommon". Many studies show that prohibiting cannabis did not make it any less easy for young people to get hold of it. (See also: How much pot does it take to turn a teenager into a suicidal dropout? | Linking cannabis and suicide doesn't prove causation | Cannabis use in teens, suicide and school dropout: the jury is still out)

The low volume, high frequency internet drugs market makes it hard for police to target. And even harder for teenagers to know what they’re taking. After the Future Music Festival in Sydney, 177 people will face court on drugs charges. Yet police sniffer dogs, which have been shown to be little more than a psychological deterrent, are not detecting new and emerging drugs that are widely available in Australia. These "new" drugs are freely available online and over the counter in NSW, despite amendments to the Drug Misuse and Trafficking Act to include emerging psychoactive substances (EPS) over a year ago.

There is no evidence that tough policies deter young people from using cannabis, a study has found. Analysing data about cannabis use among more than 100,000 teenagers in 38 countries, including the UK, USA, Russia, France, Germany and Canada, the University of Kent study found no association between more liberal policies on cannabis use and higher rates of teenage cannabis use. “My new study joins several others which show no evidence of a link between tougher penalties and lower cannabis use,” said Prof Alex Stevens, from the University of Kent’s school for social policy, sociology and social research.

Legalising the medical use of cannabis has not led to a surge in the numbers of adolescents using it in the USA, according to new research that surprised its authors and will encourage those hoping for relaxation of the law elsewhere. However, the findings from 24 years of data from more than one million adolescents in the 48 contiguous states did not substantiate fears that cannabis use would rise, especially among teenagers. A paper in the journal Lancet Psychiatry says that the use of cannabis by adolescents was already higher in the states that have opted for medical legalisation. But the change in the law did not lead to a jump in numbers.

The feds have been finessing their approach to vaping, amid outcries over both an outbreak of lung disease and the impact of bans of vape flavors on former smokers. The latest Centers for Disease Control and Prevention (CDC) data on the outbreak of lung disease associated with “vaping” indicate that 77 percent of over 800 reported cases⁠ (which included at least 13 reported deaths⁠) involve patients who used unregulated cannabis-derived products. Substances including vitamin E acetate or hydrogen cyanide mixed with illicit THC oils have been implicated. CannaSafe, a testing firm, conducted independent analyses on 10 sample products linked to lung disease, and found that all contained a fungicide that could turn into hydrogen cyanide, which is extremely poisonous and flammable, when heated.