Question

Why was sand a health threat for Egyptians?

Answer 1

One reason it was a health threat is it caused teeth to become ground down which would then lead to infections.  The same was true with their eyes and lungs, sand would be blown into their eyes or inhaled into their lungs and then could cause infections.

Answer 2

The Middle East is known for Dust Storms or Dust Clouds. The US had an event that is called the Dust Bowl this was in the 1920's or 1930's. With high winds it would pick up Sand/Dust and carry it for miles and miles. The sand can cause health problems. If you breathed it in you will have a hard time breathing. This is why when these storms happened people would take cover or cover their face and eyes. If sand gets into your eyes and it's large amounts of it, you possibly go blind. Breathing all that sand can cause them to get sick because of bacteria. You don't know what type of bacteria it is. So it could be dangerous. During the Dust Bowl the storms caused crops to be destroyed and were taller then 50 ft so basically taller then about a four story building.