Brain is preserved in all of the following, except:

Preservation of additional viscera: (1) Hea: strychnine, digitalis, yellow oleander. (2) Brain: alkaloids, OPC , opiates, CO, cyanide, strychnine, barbiturates; and volatile organic poisons. (3) Spinal cord: strychnine and gelsemium. (4) C.S.F: alcohol (5) Bile: Narcotic drugs, cocaine, methadone, glutathione, barbiturates (6) Vitreous humour: alcohol, chloroform, cocaine. (7) Lung: one lung in gaseous poisons, hydrocyanic acid, alcohol, chloroform, etc. (8) Bone: arsenic, antimony, thallium or radium. (9) Fat: 10 gm from abdominal wall or perinephric region in cases of poisoning by pesticides and insecticides.