Question is for how long one has to be exposed to given PM 2.5 ammount to see such reduction. BTW. In Cracow, Poland we have a second month of very high PM2.5

Question is for how long one has to be exposed to given PM 2.5 ammount to see such reduction. BTW. In Cracow, Poland we have a second month of very high PM2.5 levels (lower ones are about 40 ug/m3, highest being above 200 ug/m3) see http://monitoring.krakow.pios.gov.pl/dane-pomiarowe/automatyczne/parametr/pm2.5/stacje/202-242-211/miesieczny/01.2017 http://monitoring.krakow.pios.gov.pl/dane-pomiarowe/automaty... or http://aqicn.org/city/poland/malopolska/krakow/aleja-krasinskiego/pl/m/ http://aqicn.org/city/poland/malopolska/krakow/aleja-krasins... Too much coal based heating and too little wind.