Is it safe to use normal garden hose for water??

Years ago, the black inner layer of your green garden hose was a pvc compound stabilized with heavy metals including lead. The major hose makers no longer use lead in any hose, but if you buy the white drinking water hose you know what you're getting.
On a hot day, the cheap green hose will transfer an odor or a taste to the water. It may be safer nowadays (no lead) but it doesn't taste great.