Water is very essential for life. The average daily water need per individual is 150-200 litres. Standard of health depends on the quantity, quality and purity of water. A number of diseases are caused due to lack of safe drinking water. Statistics has shown that the rate of various diseases are reduced by an improvement of water supply.
Water borne diseases
Water may get contaminated with a number of impurities like dust particles, dissolved gases, minerals and micro-organisms. All of them are likely to produce a verity of diseases. Water borne diseases may be classified as:
1. Diseases due to the presence of infectious agents:
- Bacterial diseases: cholera, dysentry, typhoid fever, gastroenteritis.
- Viral diseases: hepatitis, poliomyelitis.
- Protozoal diseases: Amoebiasis, giardiasis.
- Worm infestation: Round worm, thread worm, tap worm and guinea worm.
2. Diseases due to the presence of chemical agents:
- Fluorides: Dental and skeletal fluorosis.
- Nitrates: Infantile methemoglobinemia.
Safe and wholesome water
Safe water is one which does not harm the consumer even if ingested for prolonged periods.
Wholesome water is one which agreeable to use since it does not have unpleasant taste or appearance.
Portable water is drinking water which is acceptable since it is both safe and wholesome.
Criteria for safe and wholesome water
- Free from pathogenic organisms.
- Free from toxic chemical substances.
- Fit for domestic use.
- Pleasant in taste.