The cannabis industry's next war: How strong should its weed be?

The nation’s booming weed industry has a potency problem.

As more and more states legalize marijuana, companies are facing new pressure from lawmakers across the country — and Capitol Hill — to limit the strength of their products. It’s a level of scrutiny that comes with being allowed to operate in the open after decades in the shadows.

The steadily rising levels of THC — the component of marijuana that gets users high — is causing widespread concerns about the public health consequences. Even in pioneering states like Colorado and Washington, where recreational marijuana sales started in 2014, lawmakers are debating whether to put caps on THC potency.