How does the pollutant lead commonly get into water sources?

Question

Possible Answers:
It is a byproduct of reactions that occur with pollutants and organic matter in water systems.
It leaches into water through the old and corroded plumbing components of the water systems.
When runoff reaches groundwater it often has lead as a pollutant.
It is dumped into waterways from industrial waste.

Answer 1

It leaches into water through the old and corroded plumbing components of the water systems.