Drinking water or water fit for human consumption is water that can be consumed without restriction for drinking or food preparation.

• Water regulates the temperature of the earth. It also regulates the temperature of the human body, carries nutrients and oxygen to cells, protects organs and tissues, and removes waste.
• Adverse health effects from contaminants, such as lead, that can occur in drinking water include acute effects that may have an immediate health impact and chronic effects that may occur if contaminants are ingested at unhealthy levels over many years.
• Lead enters the water through contact with the plumbing. If you want to know if your home has drinking water that contains unhealthy levels of lead, test your water for lead. Boiling your water does not remove lead.
• The U.S. Environmental Protection Agency (EPA) sets health-based standards to protect drinking water. The U.S. Environmental Protection Agency (EPA) sets health-based standards to protect drinking water.
• The Agency identifies contaminants that could adversely affect public health and occur in drinking water at a frequency and at levels that pose a threat to public health. EPA identifies which contaminants require further investigation and determines the contaminants to be potentially regulated.

Indicators of the impact of drinking water supply and sanitation.

WHO sanitarians estimate that:

88% of diarrhoeal diseases are caused by unsafe water supply and poor sanitation and hygiene.

An efficient and well-managed drinking water supply system reduces diarrhoeal morbidity by 6-21%, if severe consequences are counted.

Hygiene measures, including hygiene education and hand-washing, can reduce the number of diarrhoea cases by up to 45%.

Improving drinking-water quality by treating domestic water, e.g. by chlorination at the point of consumption, can reduce diarrhoea episodes by 35-39%.

Source: Environmental Protection Agency