Question

one of the most important reasons for only using reliable water source is to reduce?

Answer 1

one of the most important reasons for only using reliable water source is to reduce : Infections

Without laboratory testing, it is impossible to actually known what type of contamination that a water source have.
For all we know, a water source could contaminated with chemicals or bacteria that could caused internal infections within our body

Answer 2

The right answer is The number of parasites, such as Cyclospora Cayetanensis.

The health risks associated with water are due to the use of polluted water, unfit for the intended use, for example:

- Consumption of water (beverage, ...), live products or products grown in aquatic environments (shellfish, ...);

- Swimming ;

- Use in a hospital environment (hot water, ultra pure water, ...).

Depending on the pollutants, the health risk is of an infectious nature (viruses, bacteria, parasites, fungi), chemical (mineral, organic), or physical (thermal, radioactive).

The risks involved are more or less long term. Some are known and proven for health, and others are suspected or even emerging.