You make a good point but I think adding QALYs to this discussion is unnecessary complication, for one reason: like most public health menaces, pollution will impact lifespan and healthspan proportionatly, ie you’ll die sooner and also live worse years if you’re exposed. There is a proportionately better chance of ageing well and dieing later if you avoid it.

QALYs really shine when measuring a one-off risk, such as an operation or cancer treatment that might add lifespan but decrease healthspan. If QALY data exists for pollution that’s great, but I think we can easily extrapolate the impact in healthspan from the toll in lifespan.