Every drink of tap water you take has already been drunk by 10 people before you, which means it’s been 'recycled' by another creature. Paul Frijters wrote a piece at Economics.com.au showing the math used to figure out how many people your refreshing drink has passed through over the years.
It’s not a surprise; the water we have now is the same water that’s been on the planet since the beginning, and Paul says that 10 is a low estimate; his math suggests the real number is closer to 25.
Source: LadBible