The air polluted with PM particles in Smederevo, Kostolac and many other places in Serbia, has a negative effect on the health of their residents. Nevertheless, on days when pollution levels are the highest they are not notified of that because many data are publicized too late – a month or even a year later, according to CINS’ research. And while the Serbian Environmental Protection Agency publishes data, CINS’ interlocutors believe that local measurements that are not included in the official assessment of air quality should be more important.