Water: Public Health & Environmental Health
Water is a fundamental determinant of health. From an epidemiological and environmental health perspective, it acts as a vehicle for disease transmission and a vital resource for community hygiene.
Key Public Health Considerations
| Area | Key Concepts |
|---|---|
| Water-borne Diseases | Cholera, Typhoid, Hepatitis A/E, Giardiasis, Cryptosporidiosis. |
| Water Quality Standards | Indicator organisms (E. coli, Coliforms) are used to test for fecal contamination. |
| Water Treatment | Sedimentation, Coagulation, Filtration (Slow/Rapid sand), Disinfection (Chlorination). |
| Hardness | Temporary (carbonates) vs. Permanent (sulfates/chlorides of Ca/Mg). |
High-Yield Clinical Notes:
- Chlorination: The most common method of disinfection. The orthotolidine test is used to measure free residual chlorine (ideal: 0.5 mg/L for 30 minutes contact time).
- Water-Washed Diseases: Diseases resulting from lack of water for hygiene (e.g., Trachoma, Scabies).
- Fluoridation: Optimal concentration (0.5–0.8 mg/L) prevents dental caries; excess causes fluorosis.