Do not brush your teeth with the first glass of wa

A survey found that more than 23 of the taps have excessive heavy metal precipitation, so it is best not to drink the first cup. Overnight, standing water in pipes can collect bacteria, metals, and other contaminants. When you first turn on the tap in the morning, this water (often called "stagnant" water) may contain higher levels of these impurities.

Brushing with water when first rinsing the faucet can introduce these contaminants into your mouth and come into contact with your teeth and gums. While the risk of serious injury from brushing with this water is generally low, some people prefer to err on the side of caution and wait until the water is clear and cold before brushing with it.

To minimize the potential for exposure to contaminants, it is recommended to let the water run for a while before drinking or brushing your teeth, usually about 30 seconds to a minute. This allows fresh water from the main water source to flush away water that may have accumulated in the pipes overnight. Additionally, using a water filter or purifier can help further improve the quality of tap water and make oral hygiene practices safer.