introduction to animal poisons, forensic toxicology

animal poison msc1.pptx

1. By P.S.Bodele M.Sc. forensic science NET/SET Animal poisons

2. Introduction poisons originated from living organisms i.e. animals. Snakes are the most popular among these type creatures besides other known venomous organisms like, fishes, insects, etc . Similarly, some animals use poisons as a weapon of predation or self- defense or both . Poisonous animals, usually derive their toxins through the food chain. As such, poison is often a metabolite produced by microorganisms, plants, or animals . ANIMAL POISON AND VENOM:

3. Venoms content: Lipid Polypeptides and enzymes Amines Low and high mol. Weight proteins Amino polysaccharides Histamine Free amino acid Quinones Glycosides Steroids venom shows toxicity due to conc. or dose

4. Scorpions: Palamnaeus , handrarus, vejovis, Nebo, centruroids are some species that are responsible for poisoning. Compositions: low mol. Weight proteins Peptides Amino acid Nucleotides Salt Neurotoxins Symptoms: Affect voltage gated ion channels Localized pain, fever Swelling, weakness, muscles, fasciculation Mild parasthesia. Treatment: Diazepam Antihypertensive drug Bed rest and positive pressure breathing

5. Venom is clear colorless toxalbumin Main toxins includes: Phospholipase Acetyl cholinesterase Hyaluronidase Scrotinin Buthus species in India contains phospholipase -A which causes GI and Pulmonary hemorrhage.

6. BEE: Apis mellifera, Apis dorsata, Apis florea etc . are some poisonous species. Compositions: Active melittin Phospholipase Hyaluronidase Histamine Dopamine Mast cell degranulation peptides Symptoms: Respiratory dysfunctioning Intravascular Hemolysis Hypertension Myocardial damage Renal failure Treatment: Hydrocortisone(injection) Fab based antivenin Venom : Hymenoptera consist of Biogenic amines- histamine, acetyl choline, 5-hydroxytryptamine Enzymes- phospholipase, hyaluronidase Toxic peptide- kinins in wasp and mast cell degranulating peptides in bees.

7. SNAKE: Study of snake is called herpetology . And poisoning by snake is ophitoxemia . Among more than 3500 species of snakes approx. 400 are venomous to human There are 238 species of snakes in India out of which 42 are poisonous Ex. King cobra (ophiophagus hannah ) N aja naja (common cobra) Deboia rusellii (Russell’s viper) Bungarus caeruleus (Krait) Echis carinatae (saw – scaled viper) Venomous family: Elapidae – cobra, krait, mamba, coral snakes Hydrophildae –true sea snakes Laticadidae –sea kraits Viperidae –vipers , adder snakes (European viper Crotalidae (subfamily) –pit viper, rattle snake, moccasins Compositions of snake venom: Na, K, Ca, Mg, ions etc. Heavy metals like Zn, Co, Fe, Mn, Ni etc. Near about 25 different enzymes

8. Major enzymes: Arginine ester hydrolase- break ester found in crotalidae, Viperidae , sea snake and it is absent in Elapidae Thrombin – for clotting Found in crotalidae and very little in sea snakes and viperidae Collagenase-Digest collagen Found in crotalidae and Viperidae Hyaluronidase- damage connective tissue found in all poisonous s nakes Phosphatase- break phosphate bond Almost in every snakes Phospholipase – break down phospholipid Almost in every snakes Phosphodiesterase- break Phosphodiester bond Almost in every snakes Nucleotidase – break down nucleotide Almost in every snake

9. snakes poisonous Non poisonous Head scales are small Belly scales are large Nocturnal Tow teeth mark( .. ) Tail is compressed Head scales are large Belly scales are small 24 hours working Semicircular mark Blunt tail

10. Major Indian poisonous snake: Krait Sever pain in abdomen No swelling or burning sensation or pain at bite spot Drowsiness Hemolysis, paralysis of trunk and limbs Cobra Bitten spot turns bluish and blackish Burning sensation Inflammation and swelling Gradual paralysis, convulsion Eyelids drop and pupils contract Speaking and swallowing difficulty Depressed respiration

11. Viper: Hemolytic and hemotoxic i.e.lysis of RBC Swelling and pain at bitten spot Reduction in bitten spots Heart weakness Pupils dilated Death due to loss of blood toxemia , heart failure Fatal dose: Dried cobra venom: 12-15 mg Dried viper venom: 15-20 mg Dried krait venom: 5-6 mg Dried saw scaled viper venom: 8 mg Fatal period: Death may occur instantaneously from neurogenic shock resulting fright. In colubrine bite: ½-24 hours In viperian bite: 2-4 days

12. Common krait : Vipers : Sea snakes:

13. ACTION OF VENOM: Neurotoxic : These act primarily on motor nerve cells and there action resembles curare Neurotoxins of cobra venom produce both convulsion and paralysis Neurotoxins of krait venom cause only muscular paralysis Local symptoms at site of bite is minimum compared to the vasculotoxins ex,. Elapid (cobra, king cobra, common krait etc.) Vasculotoxic: These venom produces enzymatic destruction of cell wall and coagulation disorder Endothelium of blood cell is destroyed, RBC are lysed and other tissues are destroyed Blood from such patients fails to clot normally because of extremely low level of fibrinogen Sever swelling at bite area. Ex. Viper snake

14. Mycotoxic: These venom produces generalized muscular pain followed by myoglobinuria after 3 to 5 hours ending in respiratory failure in fatal cases. Ex. Sea snakes Antivenin : Antivenin used for the treatment of snake bite cases It neutralized the circulating toxins only, not the toxins fixed in tissues Specific antivenin prepared by hyper immunizing horse against the venom of four poisonous snakes i.e. Cobra Common krait Russell’s viper Saw scaled viper 1ml of antivenin will neutralized 20MLD of king cobra.

15. Analysis of snake venom: There are different methods of analysis for different venoms of snake or for different snakes The skin portion around the bite area may be source of venom for examination for its constituents by special tests. Test for cholinesterase and thromboplastin in and around the bite area: Aqueous wash from bite area may be tested for activity of cholinesterase and thromboplastin Cholinesterase- in case of bite by colubrine snake Thromboplastin – in case of bite by viper snakes Toxicity test: For confirmation f snakebites Aqueous wash from bite area or serum of infected person is injected to the fowl(cock) with or without antivenin Death of fowl without antivenin and survive of foul with antivenin confirms the snakebite.

16. 3. Clot quality test: Blood of infected person is taken in a capillary tube and place the capillary in horizontal manner for 30 min at room temp. It is then raised vertically Non clotted blood due to consumption of fibrinogen or defrbrination runs out of its own accord This is useful test for diagnosis of viper bite compared to the test for coagulation 4. Gel diffusion test: Antigen – antibody interaction Wash from bite area or serum of victim in one well(antigen) Antivenin placed in another well. Reaction for overnight i.e. . Diffusion If precipitin line observed then reaction is positive 5. Immuno assay: Antigen – antibody interaction Sometimes labeled antigen or antibodies with radioisotopes used and the reaction is very sensitive and specific i.e. immuno assay. Examples are ELISA RIA EIA

17. 6. Other tests: Aqueous wash extract of bite area may be tested for presence of inorganic substances by spot test. Ex. Na, Mg, by spot test or AAS or FES and by using other instrumentation techniques.