Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Collection,Dispatch & Processing of toxicological samples.

Collection,Dispatch & Processing of toxicological samples.
Dr Faheem Sultan
Division of Veterinary Pharmacology & Toxicology
Indian Veterinary Research Institute

  • Be the first to comment

Collection,Dispatch & Processing of toxicological samples.

  1. 1. The practitioner and diagnostic laboratory staff must maintain good communication in order to complete their diagnostic efforts efficiently and provide optimal service to the client. The laboratory staff can provide guidance when there are questions regarding sample collection and handling, as well as offering assistance in interpretation of test results.
  2. 2.  A detailed case history, owner, species, breed, sex, age, animal identification, clinical signs, gross appearance (including size and location) of the lesion(s), previous treatment (if any), time of recurrence from any previous treatment, and morbidity/mortality in the group.  The submission form should be placed in a waterproof bag.  Waterproof markers should be used when labelling .
  3. 3. If a known toxin is suspected, a specific analysis should always be requested.  A complete description of clinical and epidemiologic findings.  Tissues or fluids for chemical analysis should be as fresh as possible and kept refrigerated.  In rare instances a chemical preservative is required. 
  4. 4.        Samples can be preserved for 72 hr if packed in a Styrofoam box with dry ice. Plastic containers, both bags and jars, are ideal. Jars with metal screw caps should be avoided. Packed individually & well labelled. Must conform to postal regulations. If feed or water is suspected as the source of poisoning, it should accompany the tissue samples. In some instances, suspected feed may be fed to experimental animals .
  5. 5. Peripheral blood concentration has been shown to be more reliable.  Usually 20 ml of blood is sufficient and it has to be preserved in sodium fluoride of 10mg/ml and potassium oxalate, 30 mg/10 ml of blood concentration.   The glass container should be made of amber glass.
  6. 6.  Sodium fluoride protects blood from postmortem changes such as bacterial production of ethanol or other alcohols.  It also helps to protect other labile drugs such as cocaine, ntrazepam and clonazepam from degradation.  K2EDTA may also prove useful in cases of suspected fluoride poisoning.
  7. 7.  Concentrations are generally higher than in blood.  A number of metabolites may also be present.   Preserved in sodium fluoride. A sample of 20 ml is sufficient for toxicological analysis.
  8. 8.   Opiates and acetaminophen( paracetamol). It is not routinely preserved.
  9. 9. Useful for alcohols, or in diabetes and insulin related deaths.  Useful where the body has decomposed.  Biochemical tests such as urea, creatine, glucose, lactose and alcohol.  Is preserved with sodium fluoride (10 mg/ml) 
  10. 10.  Rarely required for toxicological analysis.  The CSF sample has to be preserved in sodium fluoride.
  11. 11.  Like PERICARDIAL and SYNOVIAL FLUIDS can be used for toxicological analysis like alcohol.
  12. 12. The most important tissue because it concentrates many substances.  Establish whether acute or chronic toxicity.  A minimum of 100 gm is sufficient for toxicological analysis. 
  13. 13.  Rumen, stomach and small intestine with their contents.  For toxins taken orally as the concentrations will be many times higher than in other fluids.
  14. 14. Analysing chronic poison ( heavy metals) or drug of abuse (opioids).  Distinguish between episodic or continuous exposure.  For those poisons which may have already been eliminated from the body by the time of death.  About 500 ug (20 – 30 hairs ) & the whole nail. 
  15. 15.  In decomposed body, if maggots are present 20 gms of maggots .  Saturated common salt as the preservative.  It only provides qualitative information.
  16. 16.  The injection site has to be preserved. The skin sample with the underneath muscle tissue around the injection site area must be preserved along with a control sample .  Preserve in saturated solution of common salt. 
  17. 17. SUSPECTED POISON SAMPLE COLLECTION REMARKS Ammonia Whole blood ,Plasma Urine,Rumen contents Frozen Frozen/1-2 dps HgCl2 Anticoagulants (warfarin and related compounds) Whole blood Liver Feed Stomach contents Heparin or EDTA Refrigerated Arsenic Liver Kidney Urine Ingesta Feed Chlorates Stomach contents Urine Feed Frozen, in airtight container Chlorinated hydrocarbons Cerebrum Ingesta Body fat Liver Kidney Kidney Use only glass containers Avoid contamination Refrigerated or frozen
  18. 18. SUSPECTED POISON SAMPLE REMARKS Copper (and Ni, Fe, Co, Cr, and Tl) Kidney Liver Serum Feed, Feces Whole blood Cholinesterase Serum Cerebellum, CSF Frozen Cyanide Forage Whole Blood Liver Rush to laboratory or ship promptly, frozen in airtight container Dicoumarol Forage Liver
  19. 19. SUSPECTED POISON SAMPLE COLLECTION SAMPLE COLLECTION Ethylene Glycol Serum, Urine, Kidneys Fresh plus formalin fixed Flourides Bone, Water Forage, Urine Bones are the best. Herbicides Treated weeds, Urine Ingesta, Liver or kidney Ionophores Feed, Rumen contents Heart, Skeletal muscle Lead (also Hg, Mo, Ni, and Tl) Kidney, Whole blood Liver, Urine Heparinized blood preferred Mercury and molybdenum Kidney, Whole blood Liver, Feed Heparinized blood Mycotoxins Grain, forages Liver, kidney Specific tests
  20. 20. SUSPECTED POISON SAMPLE REMARKS Nitrate Forage,H2O,Bodyflds(e.g. Refrigerated ,aqueous humor) Organophosphates (and carbamates) Feed, Ingesta Urine Also send urine, blood, and stomach contents from normal animals. Phenols Gastric or rumen contents In air tight container. Polychlorinated(polybro minated)biphenyls Fat,Cerebrum Feed Rumen pH Ingesta Frozen Selenium Whole blood, Feed Liver, Hair clippings Heparinized Sodium (NaCl) Brain, Serum CSF, Feed Other half fixed in formalin
  21. 21. SUSPECTED POISON SAMPLE REMARK Sodium fluoroacetate (1080) Stomach contents Liver Frozen Strychnine (and some Liver other convulsants such as Kidney bromethalin) Stomach contents Sulfates Water, Brain Fixed in formalin Vitamin A (also D and E) Liver, Serum Frozen Urea Feed Vitamin D 3 (rodenticides) Kidney Zinc Phosphide Liver, Gastric contents Frozen Zinc Use trace mineral tubes Liver, Kidney Serum
  22. 22.  The ideal samples are best sent in their original state without adding any preservative in a refrigerated storage (4C) within few hours.  For long term storage it has to be kept in freezer analysed and disposed off.  The most commonly used preservative for visceral tissues are saturated solution of common salt.  The other option is rectified spirit (90% ethanol) except in cases of poisoning due to alcohol, chloral hydrate, chloroform, phenol formaldehyde, ether, and phosphorus. (-10C) until
  23. 23.  Properly sealed and labelled.  Avoid loss during transport.  Comply with health and safety regulations.   The use of tamper-evident seals. Should be handed over to the investigating officer after obtaining proper receipt.
  24. 24.  The choice of method for testing is highly dependent on: 1) Kind of substance one expects. 2) The material on which the testing is performed.
  25. 25. PROCESS/TEST SUBSTRATE GAS-LIQUID CHROMATOGRAPHY VOLATILE ORGANIC COMPOUNDS. DESTRUCTION OF THE ORGANIC MATRIX DETECTION OF METALS BY CHEMICAL OR THERMAL OXIDATION. THE REINSCH TEST, EMISSION SPECTROSCOPY OR X-RAY DIFFRACTION. DETECTION OF METALS THIN-LAYER CHROMATOGRAPHY, GASLIQUID CHROMATOGRAPHY AND IMMUNOASSAY. PESTICIDES, NATURAL PRODUCTS, POLLUTANTS AND INDUSTRIAL COMPOUNDS OLDER METHODS INCLUDE: SPOT TEST THE MARQUIS REAGENT, MECKE REAGENT, AND FROEHDE'S REAGENT FOR OPIATES MARQUIS REAGENT AND SIMON'S REAGENT AMPHETAMINE, METHAMPHETAMINE & OTHER ANALOGS THE SCOTT'S TEST DUQUENOIS REAGENT FOR COCAINE MARIJUANA AND OTHER CANNABINOIDS

×