Chemicals widely used to flavour e-cigarettes may impair our lungs' first line of defence against dirt and allergens, potentially increasing the risk of diseases such as asthma, a Harvard study has found.
Researchers found that two chemicals, diacetyl and 2,3-pentanedione, affect the function of cilia - antennae-like protuberances that are present on 50-75 per cent of the cells that line human airways.
They play a key role in keeping the human airway clear of mucus and dirt and allow people to breathe easily and without irritation.
Impaired cilia function has been linked with lung diseases such as chronic obstructive pulmonary disease (COPD) and asthma.


