The Denver Post reports the state’s Marijuana Enforcement Division has proposed final rules that include prohibiting specific ingredients in marijuana vaping products.

The updates are expected to be discussed during a public hearing Tuesday.

The ingredients include Polyethylene glycol, Vitamin E Acetate and Medium Chain Triglycerides.

Officials say the additives can be used as thinning agents for THC, which is too thick to be atomized or vaporized in vaping products.

A vaping-related lung disease has sickened nearly 1,300 people and killed at least 25 nationwide.

State health officials say there were nine cases reported in Colorado as of last week.