More than 180 different flavouring agents are currently used in e-cigarettes, many of which have not undergone thorough safety testing.

A leading expert has emphasized that when it comes to vaping, “prevention” is the only real option, given the potentially “permanent” damage it can cause.

Earlier this year, a 17-year-old was diagnosed with bronchiolitis obliterans—commonly known as “popcorn lung”—after three years of vaping. The condition is irreversible.

Donal O’Shea, Professor of Chemistry at RCSI University of Medicine and Health Sciences, has outlined the dangers of popcorn lung and the role certain flavouring agents play in causing lasting lung damage.

Writing for The Conversation, Professor O’Shea explained that the term “popcorn lung” originally came from cases involving workers at a microwave popcorn plant. These workers developed serious lung problems due to exposure to diacetyl, a chemical used for buttery flavoring.

In much the same way, flavoured vaping products also contain diacetyl. When heated and inhaled, it turns into a harmful aerosol.

“It causes inflammation and scarring in the bronchioles (the smallest branches of the lungs), making it increasingly difficult for air to move through,” Professor O’Shea says.