Yep, that's big. Photographer: Raul Arboleda/AFP/Getty Images
Yep, that's big. Photographer: Raul Arboleda/AFP/Getty Images

In Colorado, the worst surprises so far from the newborn recreational marijuana business have come from edibles -- those brownies, cookies, sodas and other sweet treats that have incapacitated big-name journalists and caused an uptick in emergency-room visits by adults and children alike. Colorado is responding with mandatory testing for THC, marijuana's psychoactive ingredient, and a limit of 100 milligrams in any edible product. Is this enough?

That will depend in part on how powerful Big Marijuana is allowed to become.

Big Marijuana is nowhere near the size of Big Tobacco, but these are early days. The pot business in Colorado -- the first state to allow sales for recreational use -- is not yet half a year old. Sales in Washington state are not expected until July.

Up In Smoke

That means Big Marijuana is in roughly the same place Big Tobacco was in the 1880s, according to a comparison of the two in the New England Journal of Medicine yesterday. At the end of the 19th century, tobacco was not in wide use, people mostly rolled their own and few of them died from smoking. It wasn't until the 1950s that half the U.S. population used tobacco, mainly manufactured cigarettes, and lung cancer killed more people than any other kind of cancer.

Authors Kimber Richter of the University of Kansas Medical Center and Sharon Levy of Boston Children's Hospital attribute this grim narrative to "tobacco-industry innovations in product development, marketing and lobbying." Big Tobacco developed curing processes that enabled smokers to inhale more deeply and get more nicotine to their brains. This made smoking at once more addictive and more toxic.

The marijuana industry is likewise increasing the potency of its products and coming up with a highly marketable array of new delivery devices -- notably in the form of edibles. By July, recreational marijuana users in Seattle will be able to buy -- in addition to cookies, brownies and the like -- cold-brewed drinks infused with coffee and 20 milligrams of THC.

Careful cultivation to increase marijuana's THC content has tripled potency in the past couple of decades, by some measures.

And those vaporizers that have been developed to minimize lung irritation? They allow users to inhale THC more often and more deeply, Richter and Levy report. Greater potency may increase the risks of addiction, traffic accidents and personal side effects ranging from memory loss and anxiety to psychosis. Not to mention overindulgence in edibles.

The marijuana market in the U.S. is still small -- it's just 7 percent of Americans 12 or older -- just as the tobacco market was before widespread smoking of machine-made cigarettes. That means it's early enough now to learn from the tobacco experience and prepare for the public-health fallout before it gets out of hand.

Richter and Levy wisely suggest that federal agencies such as the Food and Drug Administration, the National Institutes of Health and the National Highway Traffic Safety Administration collaborate on an effort to fully understand marijuana's harms and anticipate the effects of its industrialization.

To contact the author of this article: Mary Duenwald at mduenwald@bloomberg.net.

To contact the editor responsible for this article: Lisa Beyer at lbeyer3@bloomberg.net.