...and is also explosively flammable. Remember that CFCs replaced early refrigerants which were flammable and/or toxic. This memorable incident may be attributed to using a flammable refrigerant:
https://en.wikipedia.org/wiki/Cocoanut_Grove_fire
Personally, I'm against an absolutist ban on CFCs, since it was mainly their mass release into the atmosphere that caused problems, and they had great advantages in closed-system uses. This may surprise a lot of HN readers, but I have the same belief about PCBs[1] and chrysotile (white asbestos)[2] --- "the dose makes the poison". Literally everything is harmful to something in some way, so the right thing to do is to manage use such that we can maximise the benefit:risk ratio, instead of the frenzied "ban everything" attitude that seems far too pervasive today.
[1] https://www.mcgill.ca/oss/article/controversial-science-envi...
Anyway, I still wonder why ammonia fell into disuse as a refrigerent.
One reason might be that we had to evacuate our office when our small refrigerator in the pentry popped and vented all ammonia. It took a while to get sorted, and it can't have been much in that small unit.
(And I don't mean just to humans; that's only a small part of why it was banned.)
https://www.thedailybeast.com/how-rachel-carson-cost-million...
From the second article: However, studies in Europe, Canada, and the United States have since shown that DDT didn’t cause the human diseases Carson had claimed. Indeed, the only type of cancer that had increased in the United States during the DDT era was lung cancer, which was caused by cigarette smoking. DDT was arguably one of the safer insect repellents ever invented—far safer than many of the pesticides that have taken its place.
There is some recent evidence of connection to breast cancer:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4524999/
And the WHO has a few concerns:
https://www.reuters.com/article/us-health-cancer-insecticide...
CDC Has a balanced view (though article is old): https://www.cdc.gov/nceh/clusters/fallon/ddtfaq.htm
That said the studies in question ask about very high usage, it's likely that more controlled sprays would be less damaging. That's the point I'm making, using chemicals responsibly can mitigate overall risk while maintaining their benefits. You don't have spray it in buckets everywhere (the procedure during the study period above) to do a good job of mosquito control. Plus you may save far more lives due to less malaria.
EDIT: In re. non-humans, I'm less familiar with that, but I'm an unabashed species-ist, I care that more humans live. If that has some environmental harm, then lets mitigate or try to reduce harm, but humans come first.
Thats missleading, because we don't really use pesticices against mosquitos anymore.
Main "pesticide" today is a living bacteria which targets Mosquitos directly and apparently with not much side-effects to the nature besides reducing mosquitos and totally non-toxic to mammals.
One would need to assess what if any damage the decrease or extinction of a particular species would cause to the ecology as a whole and the other life forms in it, humans included.
DDT - May not have been anywhere near as bad as first thought, and replaced in part by these compounds, which themselves are being banned now. Also there's some argument that extensive use of DDT was key to ridding the US of malaria, we banned it worldwide, taking out one of the weapons in mosquito control. One could make an argument that banning DDT has killed people b/c increased incidence of malaria. It's hotly debated, but it's not a bonkers view, and most of those deaths would be in the 3rd world.
Cadmium Paints - Yes and no, artists still say it's not the same, and the replacements in industrial scale aren't always as good on a variety of fronts (https://www.bloomberg.com/features/2018-quest-for-billion-do...). Also not sure they're as affordable.
CFCs (then some HCFCS) - Good thing to ban without a doubt, but replacements are more expensive. The ACs made with the new gasses are more expensive, which has a real human cost: (https://www.nytimes.com/2007/02/23/business/23cool.html)
I'm not making an argument for or against this particular ban or any of the bans above. I am making an argument that these bans are not without costs, and will almost certainly come with trade-offs. Some of those trade-offs will be overcome, others are much harder, and the short run will likely have some pain in the form of higher prices.
Lets say for example we got rid of all pesticides/herbicides. Could we generate enough food to feed the world? How much more expensive would staples like rice and wheat become? How much more expensive would high-nutrition fruits and veggies become? It's possible that someday get over it, but it's not good to minimize the practical drawbacks.
I think we've gotten to a point as a society where _any_ risk of something bad is too much risk, so we ban anything that presents risk. But we're left with things where either the risk is unknown, or that are bad in other ways. The average popular discussion of environmental/health risks often neglects to ask, "what might be an acceptable risk", I think sometimes the risk is worth it.