TUESDAY, Dec. 8, 2015 (HealthDay News) — Many electronic cigarettes contain flavoring chemicals that may cause lung disease, researchers say. One such flavoring chemical, acetoin, was detected in 46 of the flavors while another, called 2,3-pentanedione, was found in 23 of the flavors, the findings showed. There are currently more than 7,000 varieties of flavored e-cigarettes and liquid, the researchers said, but there’s a lack of information on their potential health effects.