HAMILTON, Mont. (AP) — A judge is hearing arguments over Gov. Steve Bullock’s temporary ban on the sale of flavored vaping products over increased teen use and a nationwide outbreak of lung injury and deaths.

An anti-tobacco advocate said Wednesday the ban fails to address the apparent cause of the lung disease, vaping THC, while a pediatrician said it’s needed to prevent another generation from becoming addicted to nicotine.

The hearing before District Judge Jennifer Lint continues Friday in Hamilton with testimony from two more state witnesses.

The Democratic governor announced the ban on Oct. 8 and said it would take effect on Oct. 22, but vaping store owners and the Montana Smoke Free Association challenged the 120-day ban. They argued it would force them to lay off employees and put them out of business. Lint stopped the ban from taking effect until she holds a hearing.

On Wednesday, Boston University community health professor Michael Siegel said research indicates the lung disease appears to be linked to the vaping of THC, the active ingredient in marijuana, not nicotine.