Answer:
Hydrogen and Oxygen
Pureified water has been filtered or processed to remove impurities like chemicals and other contaminants, while tap water is not and it is composed of minerals that may not be seen in purified water.
Chemicals are the most common type of water contaminants. They affect both surface and underground water bodies. Industries and farming activities are the leading cause.
Alcohol: Probable human mrcinogen
Arsenic: Skin hyperpigmentalion: oxidative stress;
peripheral neuropathy; bladden skin,
liver, lung, and lymphatic cancer