i) According to FDA there are about 38 toxic contaminants of bottled water may include, Chloride, Coliform, Arsenic, Iron, Manganese, phenols, Dissolved solids, Zinc,and Flouride. It is the work of FDA to allow certain levels of these contaminants in bottled water. Higher levels than the recommended levels may be toxic and dangerous to human beings.
ii) These contaminants are from different sources, for example chloride ions or chlorine is from the disinfectant used to treat water since the compounds are chloride compounds and also other byproducts of chlorine based disinfection. The CfCs is from the plastic making the bottle if water is exposed to sunlight.