The marijuana industry is scorching hot right now, and it's no wonder that investors are seemingly champing at the bit to get their hands on a company, or series of companies, with strong double-digit growth potential.

According to cannabis research firm ArcView, the legal marijuana market could grow by roughly 30% per year through the end of the decade. Investment firm Cowen & Co. shares a somewhat similar sentiment, forecasting growth from $6 billion in legal pot sales in 2016 to $50 billion by 2026. That's good for a compound annual growth rate of better than 23%. You'd struggle as an investor to find an industry that could consistently grow its sales for an average of 23%+plus each year for a decade.

Marijuana bud resting on top of cash.

Image source: Getty Images.

The tide is shifting on cannabis

One reason why cannabis is exploding is the major shift in consumer sentiment toward the substance. National pollster Gallup found that 60% of respondents in its 2016 survey wanted to see weed legalized nationally. Comparatively, just 25% of respondents shared the same opinion in 1995, the year before California became the first state to pass a compassionate use medical cannabis law.

The aforementioned dollar figures are also an allure for businesses, investors, and governments alike. After raking in $135 million in tax and licensing revenue in 2015 on $996.2 million in legal marijuana sales, Colorado, which was one of the first two states (along with Washington) to legalize recreational pot in 2012, wound up surpassing the $1.1 billion legal-weed sales mark through the first 10 months of 2016.

Long story short, the state probably earned well in excess of $135 million in additional revenue last year. Furthermore, with the passage of Prop 64 in California, $1 billion in new tax revenue stands to be generated annually once retail sales commence.

Weed investment options worth avoiding

The enormity of these legal sales figures would probably attract most investors to the retail side of the equation, including dispensaries or marijuana-infused products, such as drinks or foods. Unfortunately, this can be a tightly regulated and highly competitive space filled with a bounty of smaller-run companies. Investing in the retail aspect of marijuana simply isn't appealing at the moment, especially with a number of inherent disadvantages still in play for the industry.

GW Pharma researcher conducting a study in the lab.

Image source: GW Pharmaceuticals.

With so few marijuana stocks trading on reputable exchanges (e.g., NYSE or Nasdaq), investors might also be attracted to the largest pot stock of the bunch, GW Pharmaceuticals (NASDAQ:GWPH). GW Pharmaceuticals has discovered more than five dozen cannabinoids from the cannabis plant, and it's testing these cannabinoids in a variety of ailments.

Arguably the most intriguing product GW Phamaceuticals has in its pipeline is Epidiolex, an experimental drug that yielded positive late-stage results in treating two types of childhood-onset epilepsy. Still, GW Pharmaceuticals appears to be at least three years away from profitability, and thus remains an unattractive option for investors.

An area of intrigue

On the other hand, marijuana breathalyzer devices could be an area of intrigue years down the road for investors.

The idea behind the marijuana breathalyzer is simple: it provides law enforcement with a way to protect our roads and drivers. Individuals who've consumed too much alcohol may be impaired behind the wheel, which is why police officers have alcohol breathalyzers, along with standard field sobriety tests, to determine the level of driver intoxication if alcohol is suspected. 

Researcher studying marijuana plants.

Image source: Getty Images.

What law enforcement doesn't have at the moment is a device that tells them, with any accuracy, whether a driver is under the influence of marijuana. What makes things even trickier is that tetrahydrocannibinol, or THC, the psychoactive component of cannabis, can stick around in the bloodstream for 30 days, meaning blood tests done at a police station, for instance, could turn up a positive result even if the individual hasn't used marijuana in days or even weeks. 

Marijuana breathalyzers would seek to separate and identify THC molecules in a subject's breath so that a law enforcement officer can determine if 1) the individual has used marijuana recently and 2) perhaps some level of intoxication.

Currently, the breathalyzer market for law enforcement has an estimated value that's north of $500 million. Assuming additional states legalize recreational marijuana, this market value could rise even more.

Here's the catch

However, there's a pretty big catch that could make or break this innovative technology.

Police officer administering a breathalyzer test.

Image source: Getty Images.

When it comes to deciphering driver impairment with alcohol, there's a pretty clear line in the sand for law enforcement to follow. If a driver blows a 0.08% blood alcohol content or higher, he or she is legally impaired, and possibly subject to arrest. Even a driver that blows below a 0.08% can be charged with driving under the influence. The point here is that there's a point of reference for law enforcement.

When it comes to measuring THC content, there's no point of reference or study that suggests what level of THC in the body is considered dangerous. Making matters more complicated, the only way a "safe" level could likely be determined is through a lot of federally funded testing.

Mind you, the schedule 1 status of marijuana at the federal level makes running clinical studies on pot extremely difficult. In other words, there's this repeating cycle of needing more evidence to set up a series of guidelines that law enforcement can follow, but this evidence is unable to be attained due to the restrictive nature of the federal government's view of marijuana.

If law enforcement agencies don't have a consistent way of determining whether a driver is impaired, then getting marijuana breathalyzer technology offer the ground could be difficult.  

One more risk worth mentioning

It may also be worth mentioning that there are only a small handful of marijuana breathalyzer developers at the moment, and they're penny stocks that trade on the over-the-counter exchanges, which are inherently risky and dangerous investments. 

Street sign implying risk ahead.

Image source: Getty Images.

Companies that trade on the OTC exchange, which has admittedly done a good job of improving reporting standards in recent years, may have a few shortcomings. For example, listing standards on OTC exchanges still aren't considered as tough as being listed on the NYSE or Nasdaq, meaning getting accurate and up-to-date information may not always be easy.

For that matter, many OTC penny stocks are usually avoided by mutual funds and hedge funds. This can lead to high levels of volatility, which can be unsettling for investors who aren't aware of the risks.

While the risks can't be ignored, marijuana breathalyzer technology has the potential to be a game-changer. And, rest assured, if a legitimate non-OTC company working on this technology appears, we'll be sure to report on it.

Sean Williams has no position in any stocks mentioned. The Motley Fool recommends Nasdaq. The Motley Fool has a disclosure policy.