> As best as I can tell, the risk is close to zero for minor and occasional exposure in otherwise healthy individuals. I'm open to seeing hard evidence to convince me otherwise.
Asbestos is interesting in that the mechanism of carcinogenicity is very well-studied and well-understood. The fibers get into the lungs; the body can not get them out of the lungs; they cause persistent cell-damage as they mechanically rupture lung cells; and then the resulting chronic inflammation eventually causes cancer.
Because it's so well understood, we also know how to protect against asbestos. If the fibers are never airborn, they can't get into the lungs. If you're wearing an N95 mask or respirator, they can't get into the lungs. If you can cough them out in the moment, they don't stay in the lungs. Once they're in the lungs, you're pretty well screwed. It's a sliding scale of how screwed, with more exposure causing more cancer risk, but the fibers are not coming out and will continue rolling cancer dice while they're in there.
Having asbestos in your walls or ductwork is not going to kill you - the asbestos fibers aren't in the air. Doing a DIY reno on your asbestos-containing walls absolutely can kill you, and there have been cases of mesothelioma linked exactly to that.
> the fibers are not coming out and will continue rolling cancer dice while they're in there
This is rather alarmist. The truth is more nuanced. This resource [1] lists a variety of biological mechanisms that work to remove asbestos fibers from the lungs beyond simply coughing them out, such as via "alveolar macrophages".
> Doing a DIY reno on your asbestos-containing walls absolutely can kill you
This is true, but if this made any readers anxious, it's important to note that "light, short-term exposure rarely causes disease" and that it is "not uncommon for homeowners to do a renovation and then realize afterward that they disturbed asbestos products. Fortunately, the risk from this is low." [2]
My advice is that if you are going to renovate your home, unless it is quite new and you have good reason to believe there is no risk of asbestos contamination, you should assume that materials like tiles, plaster, drywall, insulation, etc., may contain asbestos, and get them tested before commencing. However, if you have renovated in the past and are anxious about exposure, chill out. You can't change anything now, and unless you were renovating regularly, you'll very likely be fine.
Remember that if you live in a rural area, you can be exposed to asbestos via natural weathering of rock. If you live in an urban area, you have likely been exposed to asbestos via construction and demolition work taking place nearby.
> If you're wearing an N95 mask or respirator, they can't get into the lungs
A random N95 mask is not gonna save a random Joe from asbestos. If you study how masks and respirators work, you will find that you need to be clean-shaven, the respirator must match the shape of your face and have a good seal, etc. People who work with hazardous substances spend a good amount of time on this.
NHS had to discard huge number of masks during COVID because they weren't the right shape and weren't forming a seal.
In some cases, that's good enough - general dust, woodcutting, etc. For highly toxic substances, it won't save you.
Lots of non-banned substances are more dangerous to breathe than asbestos. I understand the risks because I spent 20 years working in a building containing asbestos, and received annual notifications and warnings. It's been banned for use in construction for over 30 years, so I don't see how the EPA ban will make much difference.
No. Because of their needle shape, they wander deep into the tissue. The notoriously associated cancer is found in the mesothelium, a layer around the lungs.
It probably could[0] be done, but good luck getting an FDA approval.
[0]Speaking of smokers specifically, it is entirely possible to 'breathe' oxygenated liquid per fluorocarbons ('PFAS') which would very likely dissolve and 'wash out' tar from the lungs.
Asbestos is interesting in that the mechanism of carcinogenicity is very well-studied and well-understood. The fibers get into the lungs; the body can not get them out of the lungs; they cause persistent cell-damage as they mechanically rupture lung cells; and then the resulting chronic inflammation eventually causes cancer.
Because it's so well understood, we also know how to protect against asbestos. If the fibers are never airborn, they can't get into the lungs. If you're wearing an N95 mask or respirator, they can't get into the lungs. If you can cough them out in the moment, they don't stay in the lungs. Once they're in the lungs, you're pretty well screwed. It's a sliding scale of how screwed, with more exposure causing more cancer risk, but the fibers are not coming out and will continue rolling cancer dice while they're in there.
Having asbestos in your walls or ductwork is not going to kill you - the asbestos fibers aren't in the air. Doing a DIY reno on your asbestos-containing walls absolutely can kill you, and there have been cases of mesothelioma linked exactly to that.