There are many different types of preservatives like Benzoic acid, Calcium Sorbate, Erythorbic Acid, Potassium Nitrate and Sodium Benzoate. Some act like antioxidants used for slowing down spoilage like Ascorbyl Palmitate, Butylated Hydroxy anisole (BHA) and Butylated Hydroxytoluene (BHT
before it evaporated into the air, it was on the Earth...and it could have been contaminated/dirtied. There isn't a process during evaporation that cleans water...you have to purify it yourself.
