Leo DiCaprio -- Lung Association Calls Him Out For 'Deeply Troubling'

Leo DiCaprio may have won a SAG award, but he's lost respect from the American Lung Association for his e-cigarette display at the ceremony.

The actor was sitting at a table Saturday during the awards presentation, smoking a vape pen.

It's illegal to smoke vape pens in the city of L.A. in restaurants, bars and other public places, but interesting, the prohibition does not apply to "theatrical production sites." Presumably, the Shrine Auditorium, where the SAG awards were held, qualifies as a theatrical production site.

Nevertheless, the American Lung Association is now calling Leo out, calling his conduct "deeply troubling." The Ass'n notes vape pens expose others to secondhand dangers, including cancer.

We reached out to Leo's people ... so far, no word back.