White or grayish particles in your water can often be attributed to two different sources, both of which pertain to the condition of the hot water tank.
There is no health risk associated with either situation.
The characteristics of the particles will help determine the source:
If you have white, gray, or dark gray particles that give off bubbles when submerged in white vinegar, you most likely have calcium carbonate particles. These particles are often formed from the hardness of Columbus water when it is heated over 140 degrees Fahrenheit (60 degrees Celsius) in your hot water tank. To help prevent it, you should turn the temperature down on the tank. If your hot water tank has calcium carbonate deposited in it, use caution and follow the manufacturer’s directions for shutting down, draining, and re-starting your hot water tank.
If you have white particles that reduce water flow by clogging the aerators on your faucets, and that do not give off bubbles when submerged in white vinegar, you most likely have a disintegrating dip-tube. These particles are formed when the plastic dip-tube from the hot water heater degrades and disintegrates in the tank. Please consult with your tank’s manufacturer. You will need to have the dip-tube replaced either by the manufacturer, or a qualified technician.