Very interesting question! Not directly related, but I found this - https://www.sciencedaily.com/releases/2017/07/170707211420.htm https://www.sciencedaily.com

Very interesting question! Not directly related, but I found this - https://www.sciencedaily.com/releases/2017/07/170707211420.htm https://www.sciencedaily.com/releases/2017/07/170707211420.h... "Even though producing concrete causes air pollution, concrete buildings in urban areas can serve as a kind of sponge adsorbing sulfur dioxide to a high level," Maybe the analysis they did and how they did it, might be interesting?