Shatter, budder and other cannabis concentrates that can be consumed using small, portable vaporizers have become very popular in legal states. In Canada, however, vapes won't be part of the legal framework come October 17 because the Canadian government is concerned about their impact on public health and safety.

Many lawmakers are alarmed by the the high levels of THC commonly found in concentrates. While the average bud contains approximately 10 to 25 percent THC, concentrates commonly boast 60 to 80 percent THC or more, according to PotGuide. So it's easy for inexperienced consumers to overdo it, which can cause massive panic attacks and other forms of psychological distress brought on by taking excessive amounts of THC.

"I think there are concerns, in terms of psychosis, in terms of anxiety," Michael John Milloy - a researcher with the British Columbia Centre on Substance Use - told CBC.

There are also concerns surrounding the production of concentrates, which often involve using butane and other potentially hazardous chemicals to extract THC from cannabis flower. In some cases, those chemicals have caused fatal explosions during the extraction process.

But banning them might cause more problems for the Canadian lawmakers. Not allowing concentrates in government-regulated stores opens up an opportunity for the black market to stay in business.

"If the government's mandate is to protect children and stamp out the black market, this is the single biggest gift that the government could give the black market," said Josh Campbell, president of the vape manufacturer dosist.

And that's a huge problem because Prime Minister Justin Trudeau has repeatedly said that closing down the black market is one of the primary goals of cannabis legalization. A goal that he probably won't be able to achieve as long as the black market is the only available channel to fill a substantial area of consumer demand. And that demand will likely be very high based on the experience of other legal markets. In Colorado, concentrates represent nearly one-third (31 percent) of all cannabis sales.

So in order for Canada's new cannabis regime to succeed, regulators will have to grapple with the sticky issue of concentrates sooner rather than later.