For blood and urine, preservative used is: (A) Sodium chloride, (B) Sodium fluoride, (C) Sodium acetate, (D) Sodium gluconate
Answer is B. For blood, CSF, vitreous humor and urine, sodium fluoride is the preservative (100mg/10ml) Ref: FORENSIC MEDICINE AND TOXICOLOGY Dr PC IGNATIUS THIRD EDITION PAGE 404