My opinion is that concerns of this particular type (metallic particles or silica particles) are over-stated. However you need to take into account:
- This area is completely outside my personal field of experience, so in effect I am arguing from a position of ignorance. (In reality there are very few people indeed whose opinion on this subject is worth anything - probably limited to pulmonary consultants specialising in industrial health issues.)
- There might just possibly be someone somewhere who could be affected by inhalation of unmeasurably small quantities of contaminants of this type.
- All you have to do, if this is an issue that worries you, is fit a filter to your device - it couldn't be much simpler. For example you can drill out the bottom end of a driptip to about 5 or 6mm and insert a small section of RYO cigarette filter, and replace it occasionally. Or, have a driptip made specifically for insertion of a replaceable filter like this.
Basically I am a pragmatist: any risk from vaping is going to be about 1,000th of that from smoking (or lower); risks can be further reduced by a little thought (such as buying the highest quality refill liquids, not the cheapest; using a filter; etc.); and if you have any reason to think you are not an average person in terms of health risks (e.g. family history of a specific illness type or other predisposition) then you could perhaps consider what additional measures you could take to minimise risk.
There are specific health issues with vaping but they are on a minute scale compared to smoking. The two principal ones I can see at this time are:
1. Vaping by a person with lungs severely compromised by smoking. People with emphysema or stage 3 or 4 COPD need to look at their options very closely indeed (emphysema patients commonly develop pneumonia as their resistance is far lower, and vaping may just possibly exacerbate this in some patients).
2. We don't know what the long-term effects of inhaling large quantities of PG, flavourings or possible contaminants are. To say otherwise is a little unrealistic. What we can reasonably estimate is that the risk is far lower than smoking - but there is a risk (unless/until such time as the epidemiology says otherwise - i.e. in about another 20 years). There are ways to reduce the risk from each one of those three components (a drastic example is to only vape unflavoured refills; or perhaps more sensibly, reduce the flavourings to a minimum, of a known issue-free type).
Inhaling materials other than air has a risk, meaning that some will suffer morbidity of some kind as a result. If 30 million smokers switch to vaping, some will die (in addition to those who eventually die as a result of smoking-induced morbidity). The gamble is that it will be a lot less than if everyone smoked; and it's a good bet. It cannot be harmless, is all. There are always going to be ways to reduce risk, in any activity, if that seems important to you.
And congrats to your cardiologist for being receptive to the benefits of ecigs.
