Pollution, Contamination, Corruption
noun, verbal noun
If the air is muddy and dirty it's because there is too much pollution in that area. You should wear a mask and be careful of contamination.
おだく
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
湖の水質汚濁を防止するために規制が設けられた。
A regulation was established to prevent the pollution of the lake.