Social & Preventive Medicine Permissible level of fluoride in drinking water as per WHO is: A 0.5 mg/litre B 1.0 mg/litre C 1.5 mg/litre D 2.5 mg/litre 💡 Explanation Permissible level of fluoride in drinking water as per WHO is: ✓ Correct Answer: C. 1.5 mg/litre