What problems occurs if the firework mixture is not pure(they are dirty or contaminated?

Fireworks cause broad air contamination in a short measure of time
Explanation:
Fireworks cause broad air contamination in a short measure of time, leaving metal particles, hazardous poisons, destructive synthetic compounds and smoke noticeable all around for quite a long time. A portion of the poisons never completely decay or break down, but instead stick around in the earth, harming all they come into contact with

D.na is the answer hope this