"... past estimates - as per previous reports by Public Health England and the Royal College of Physicians in the UK - largely relied on expert opinion and where evidence was considered it largely focused on studies of vaping aerosol and e-liquid composition with relatively few biomarker studies."
The bloggers say the studies they found suggested diverse results:
• A carbon monoxide risk for vapers that was no more than a few per cent of that faced by smokers;
• A vapers' risk, in a preliminary study, of at least half that of smokers for several other inflammatory markers of likely relevance to cardiovascular and respiratory disease; and
• Vapers' risks of 14 to 23 per cent that of smokers in most studies for cancer-related toxicants.
The cancer-related biomarker findings were "a substantial level of exposure" for vapers. "But it is plausible that some of these toxicants could be due to unreported dual use with smoked tobacco - and even exposure to second-hand smoke."
The Wellington researchers say it seems likely that if smokers shift entirely to vaping, their risk of chronic disease would be expected to decline.
But if they vape long-term they may exposed to some notable levels of toxicants that are hazardous in terms of cancer, cardiovascular disease and possibly long-term respiratory disease.
The safest option for smokers using vaping to reduce their health risk would be to switch to vaping only, as soon as possible, and to aim to quit vaping too - if possible without relapsing to smoking, "which represents the greater risk to health".
Blog site: https://blogs.otago.ac.nz/pubhealthexpert/#--ENREF--7