When medical marijuana finally became a practical reality in Hawaii in 2017, some considered this long-awaited development a major step toward the ultimate goal: the legalization of recreational marijuana.

Ten other states and the District of Columbia permit adult use of recreational marijuana, and several bills before the Legislature aim to add Hawaii to the list. Lawmakers, though, need to remain wary.

Among the measures is Senate Bill 686, which would legalize the personal use and possession of up to half an ounce of marijuana for people 21 years and older, as well as allow for sales through the medical marijuana dispensaries. Sales would carry a 15 percent general excise tax surcharge.

The arguments supporting the legislation are familiar ones: The legal sale of marijuana would bring in millions of dollars in tax revenue; there is broad public support for legalization; and marijuana is safer than alcohol or tobacco, and can be a low-risk alternative to opioids.

Perhaps. But proponents tend to gloss over the more complicated aspects of full legalization.

For one, marijuana remains illegal under federal law as a Schedule 1 drug as dangerous as heroin. Gov. David Ige is rightly leery of supporting a legally dubious state law that could be preempted. Those who write our laws should be just as careful.

There also are public safety concerns. Drugs, especially marijuana, are turning up more often in traffic fatality reports nationwide. In testimony against SB 686, the state Department of Transportation noted that 22 percent of fatal crashes between 2013 and 2017 “resulted in positive findings for marijuana in drivers, bicyclists or pedestrians.” The Honolulu Police Department also opposes legalization, citing the threat of impaired drivers.

Public health policy also comes into play. The therapeutic and pleasurable effects of tetrahydrocannabinol (THC), the main psychoactive agent in marijuana, make it a popular recreational drug. But studies have shown that heavy use, especially among adolescents, can be harmful.

It’s likely true that the general public has grown more tolerant of recreational marijuana. It’s also likely that full legalization — making smoking a joint as socially acceptable as, say, having a glass of wine with dinner — would accelerate that trend. Lawmakers must consider what that could mean.

Colorado legalized recreational cannabis in 2012. A 2018 report by Colorado’s Department of Public Health and Environment used surveys to identify trends in marijuana use in that state. Among the things that increased in 2017:

>> The number of adults using marijuana within the past 30 days;

>> The frequency of daily or near daily use among adults;

>> The variety of ways adults consume marijuana (smoking, eating, drinking, vaping, dabbing, etc.);

>> The number of homes with children where marijuana is stored, possibly increasing secondhand exposure among children;

>> The use of edibles among high school students, with a decline in smoking marijuana.

While not definitive, Colorado’s experience suggests that Hawaii can expect similar trends if recreational pakalolo expands its community presence by becoming legal to use and to sell. Is this what lawmakers want to encourage, even with a potentially big tax revenue payoff?

Of course, sometimes the law must adapt to the times. There’s no denying that a significant number of Hawaii residents use marijuana for recreation, like alcohol; decriminalization, or reducing the penalties for possession and personal use of small amounts, makes sense from a law enforcement perspective.

But while legal recreational marijuana may eventually become the norm across the country, it isn’t now, and for good reason. Like Ige, Hawaii’s Legislature should stay off this bandwagon.