Preservation of Viscera
1. Stomach and its contents
2. 30 cm small Interline and contents
3. Liver > 500 gms
4. One kidney/Half of each
5. Blood 100 cc (in NaF), (Minimum 10 ml)*
- Blood Best Specimen.
- Peripheral blood concentration ( femoral ) have been shown to be more reliable for toxicological analysis than the conventional heart blood.
6. Urine > 100 cc–(in Thymol)* [Toulene* is the best preservative for urine examination]
• The best preservative for preservation of viscera is rectified spirit.
• Most commonly used preservative is saturated sodium chloride.
• Rectified spirit is not used in:
[ Alcohol also cannot be used in case of phosphorus poisoning, because alcohol prevents the luminosity of phosphorus in dark ]
• Formaldehyde is used for preservation of Museum specimens and not for preservation of viscera for toxicological analysis.
• Formalin is 40% formaldehyde.
• NaF should be added to urine, blood, vitreous humor for Alcohol estimation and to samples of
– Cocaine (C)
– Carbon monooxide (C) ® 3C’s
– Cyanide (C)
Special Preservations :
Liver is the most important tissue because it concentrates many substances.
Spleen–It is the best organ for Cyanide poisoning. ( ? Supposedly best specimen for DNA )
Brain–Alkaloids, organophosphates, volatile organic poisons.
Bile–Narcotic drugs, cocaine, methadone, Glutathione, Barbiturates, Tranquilizers.Opiates and acetaminophen
Vitreous–Alcohol, Chloroform. [ Vitreous Humour is preserved by keeping at 4ºC for 48 hours, normally preservative is of no value..though could be preserved with sodium fluoride (10 mg/ml). ]
Lung–Gaseous poison, HCN, Alcohol, Chloroform.
Bone–Arsenic, Antimony, Thallium, Radium.
Skin–C/o hypodermic injections (10 cm radius about site with muscle and fat), snake bite.
Hair, Nails, Uterus, spinal card–When indicated.
CSF–(in 10 mg NaF/ml of fluid) in Alcohol intoxication.
Body Fat—Endrin , DDT(Organo Chlorines).
Muscle–When internal organs badly putrified.Skeletal Muscle of Buttock best specimen for Toxicology in Embalming
• Viscera is stored at 4°C.
• Histopathology specimen is preserved in 10% neutral formalin/95% Alcohol.
• Virology specimen 80% Glycerol in Buffer saline.
Sumit Seth ,. Review of Forensic Medicine 4 th edition