Social & Preventive Medicine Which of the following is not true about water quality estimation – A Clostridium spores indicate recent contamination B Not more than 5% samples should have coliforms C Sodium thiosulfate added to neutralize chlorine D Coliforms must not be detectable in 100ml sample 💡 Explanation Which of the following is not true about water quality estimation – ✓ Correct Answer: A. Clostridium spores indicate recent contamination