Quick Answer
Boiling water may not remove certain contaminants such as dissolved solids, some inorganic compounds, and high levels of heavy metals. This includes salts, minerals, and other dissolved substances that cannot be vaporized by heat.
Contaminants That Boiling Can’t Remove
Boiling water is a common method for purifying water, but it has its limitations. When water is heated to its boiling point, the water molecules turn into vapor and rise to the surface, leaving impurities behind. However, this process does not remove dissolved substances that do not vaporize at the boiling point, such as salts and minerals. For example, if you boil seawater, the salt will remain dissolved in the water even after boiling.
Heavy Metals and Other Inorganic Compounds
Boiling also cannot remove high levels of heavy metals and some inorganic compounds that are dissolved in the water. These substances can be toxic and pose serious health risks if ingested. Some examples of heavy metals that boiling can’t remove include lead, mercury, and arsenic. In addition, boiling also cannot remove other inorganic compounds like nitrates and sulfates, which can be present in water due to agricultural runoff or industrial activities.
Other Methods for Contaminant Removal
If you need to remove contaminants that boiling can’t handle, other methods like chemical treatment, filtration, or ultraviolet (UV) light disinfection may be more effective. Chemical treatment involves adding disinfectants like chlorine or iodine to kill bacteria and other microorganisms, while filtration uses a physical barrier to remove impurities. UV light disinfection uses ultraviolet light to kill bacteria and viruses, making the water safe to drink.
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