May 16 (UPI) -- The benefits of marijuana may be far outweighed by its harmful consequences, a new study says.
In Colorado, motor vehicle accidents went up by 10 percent and overdose injuries and death climbed by 5 percent after marijuana was legalized in the state, according to research published Wednesday in BMJ Open.
"We need to think carefully about the potential health effects of substantially enhancing the accessibility of cannabis, as has been done now in the majority of states," Gregory Marcus, a health cardiologist at the University of California at San Francisco and study senior author, said in a news release.
The researchers looked over more than 28 million hospital records between 2010 and 2014 for New York, Oklahoma and Colorado. Compared to the other two states, they found that marijuana abuse rose after legalization in Colorado.
Since Colorado legalized marijuana in 2012, emergency departments in the state have seen 33 times more pot-related visits than before the drug was made legal, according to a study published in March. Researchers in that study pointed out that a significant number of patients reported consuming edible marijuana products, and suggested more care for appropriate doses, the potential for ingesting more THC than they expect to.
The results from the new study in Colorado are important because they could have a ripple effect on other places that have legalized marijuana. Currently, nine states have made marijuana legal for recreational use, while 28 states and the District of Columbia have allowed marijuana use for medicinal purposes.
"This unique transition to legalization provides an extraordinary opportunity to investigate hospitalizations among millions of individuals in the presence of enhanced access," Marcus said. "Our findings demonstrate several potentially harmful effects that are relevant for physicians and policymakers, as well as for individuals considering cannabis use."
However, Colorado did have 5 percent fewer hospital visits to treat chronic pain after the drug was legalized. Marcus warns people not to simplify the benefits of making marijuana legal, but rather to take a more nuanced approach when weighing the impact the drug has on society.
"While it's convenient and often most compelling to simplistically conclude a particular public policy is 'good' or 'bad,' an honest assessment of actual effects is much more complex," Marcus said.
"Those effects are likely variable, depending on each individual's idiosyncratic needs, propensities and circumstance. Using the revenues from recreational cannabis to support this sort of research likely would be a wise investment, both financially and for overall public health," he said.