In most cases, it is not necessary to filter impurities from water before boiling it on an electric stove for household use. Boiling water is an effective method to kill or inactivate harmful microorganisms such as bacteria, viruses, and parasites that may be present in the water. When water reaches its boiling point (100°C or 212°F at sea level), it becomes safe to drink from a microbiological standpoint.
However, boiling water will not remove chemical impurities or pollutants such as heavy metals, dissolved solids, pesticides, or industrial contaminants. If the water contains such chemical impurities, boiling it will not make it safe to drink. In fact, boiling can concentrate some of these chemical contaminants as the water evaporates, making the water potentially more harmful.
If you suspect that your water source may contain chemical impurities or pollutants, it's essential to have the water tested by a certified laboratory to identify any potential risks. If harmful chemicals are present, it's best to use a water purification system that is designed to remove those specific contaminants.
Water filters, such as activated carbon filters or reverse osmosis systems, can effectively remove many common chemical impurities and improve the taste and odor of water. Using a water filter before boiling is generally unnecessary for microbiological reasons, but it can be beneficial if you want to improve the overall quality and safety of your drinking water.