Tests of lung samples taken from 29 US patients with vaping-related lung injuries suggest all contained Vitamin E acetate, a discovery US officials described as a breakthrough.

The discovery of Vitamin E acetate in lung samples offers the first direct evidence of a link between the substance and vaping-related lung injuries.

The substance has also been identified in tests of product samples collected from patients with the condition, now known as EVALI (E-cigarette or Vaping product use-Associated Lung Injury).

Dr Anne Schuchet, principal deputy director of the US Centers for Disease Control and Prevention, called Vitamin E acetate “a very strong culprit of concern”.