Vaping fluid becomes more toxic to cells after it has gone through the vaping process, the results of a study published in Thorax (online, 13 August 2018) show
Researchers cultured alveolar macrophages — a specialised immune cell found in the lungs — with either condensed e-cigarette vapour or with unvapourised e-cigarette fluid.
They found that both e-cigarette vapour and fluid caused a dose–dependent reduction of cell viability but the vapour condensate was cytotoxic at lower concentrations and also led to greater cell death than the unvapourised fluid.
The condensate was also associated with inflammatory responses and a decreased ability of macrophages to destroy bacteria.
The researchers said the findings were important since previous research into the safety of e-cigarettes had considered unvapourised fluid. They noted that several of the effects reported in their study were also seen in cigarette smokers and those with chronic obstructive pulmonary disease.
“While further research is needed to fully understand the effects of e-cigarette exposure in humans in vivo, we suggest continued caution against the widely held opinion that e-cigarettes are safe,” they concluded.