What's behind the vaping-related lung illnesses?

About 90 Californians who vape have been treated for severe lung disease. Across the country, there have even been a handful of deaths. But so far, no one knows what's causing the lung damage. Nevertheless, California state health officials have come out with a warning against any kind of vaping “no matter the substance or source, until current investigations are complete.” LA County Supervisors voted to move forward with a ban against flavored tobacco products. And today, LA City Attorney, Mike Feuer, is launching a public service campaign to deter young people from vaping.