Is firework smoke dangerous?

If you are close enough to breathe in a significant amount of the smoke from fireworks, you are too close. Most of the things in the smoke are the same as you would find in wood smoke. In Disneyland they have a large firework display every night over a lake, behind their castle. They commissioned a study to look at any pollution caused after 250 shows a year for 30 years. Even with modern techniques they couldn't actually detect any pollution, so it is probably ok.