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Toxicology. Dr . SALINI CHANDRAN. Toxicology. Toxicology is the science dealing with properties, actions, toxicity, fatal dose, detection of, interpretation of the result of toxicological analysis and treatment of poisons
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Toxicology Dr . SALINI CHANDRAN
Toxicology • Toxicology is the science dealing with properties, actions, toxicity, fatal dose, detection of, interpretation of the result of toxicological analysis and treatment of poisons • Forensic toxicology deals with the medico-legal aspects of the harmful effects of chemicals on human beings • Clinical toxicology deals with diagnosis and treatment of human poisoning
poison • Poison is a substance (solid, liquid or gas), which if introduced in the living body, or brought into contact with any part thereof, will produce ill health or death, by its constitutional or local effects or both
Ideal Homicidal Poison • should be cheap and easily available • Should be colorless, odorless and tasteless • Capable of being administered with food materials without being detected • Should be highly toxic • Signs & symptoms should resemble a natural disease • Least Postmortem changes and not to be detected by any chemical tests • e.g. Fluorine and Thallium, but commonly used are Arsenic and Aconite
Ideal Suicidal Poison • Should be cheap and easily available • Should be tasteless or be of pleasant taste • Capable of being administered with food materials • Should be highly toxic • Should be capable of producing painless death • e.g. Opium and Barbiturates, but commonly used are Organophosphorus compounds and Endrin
Stupefying Poisons: Datura, Cannabis indica, Chloral Hydrate. AbortificientPoisons: Calotropis, Oleanders, Aconite, Croton, Semecarpus, Cantharides, Ergot, Lead, Arsenic, Mercury, and Potassium permanganate. Cattle Poisons: Abrusprecatorius, Oleanders, Calotropis, Organophosphorus, Arsenic, Aconite, Strychnine, etc Arrow Poisons: Abrus, Croton, Aconite, Strychnine, Curare and Snake venom etc
Types of Poisoning • Acute Poisoning – large single dose – frequent smaller - produces signs and symptoms fast • Chronic Poisoning – small doses over a period of time • Sub-acute Poisoning – between acute and chronic • Fulminant Poisoning- massive dose-death sudden due to shock ,peripheral vascular failure
Routes of Absorption • Inhalation - Fastest • Parenteral • Injections • Application on mucous memranes • Natural orifices • Intact skin
Diagnosis of Poisoning • Sudden onset of abdominal pain, nausea, vomiting, diarrhea and collapse (Arsenic) • Sudden onset of coma with constriction of pupils (Organophosphates) • Sudden onset of convulsions (Strychnine) • Sudden onset of delirium with dilated pupils. (Datura)
Diagnosis of Poisoning in the Dead • COLOR CHANGES on affected skin and mucous membrane. (black color in H2SO4 & HCl, brown in Nitric acid) • PM STAINING may be Dark brown/yellow in Phosphorus, • Cherry red in CO, • Chocolate color in Nitrates, Nitrobenzene etc. • Cyanide – Brick Red
ODOUR from nose and mouth • GARLIC like (P, Arsine gas, Arsenic, organophosphates) • SWEETISH (Ethanol, Chloroform) • ACRID (Paraldehyde, Chloral hydrate) • BITTER ALMONDS – cyanide • HOSPITAL ODOUR- Phenol(carbolic acid) • BURNT ROPE – Cannabis(marijuana) • MUSTY (fishy) – zinc phosphide , Aluminiumphosphide • ROTTEN EGG (H2S, Mercaptans)
POISONS RESISTING PUTREFACTION • 1. Phosphorus • 2. Arsenic • 3. Antimony • 4. Hyoscine • 5. Strychinne • 6. Nicotine
IPC sections • 274 – adulteration of drugs • 284 – Negligent conduct with respect to poisons • 324 – Causing hurt (including poisoning) • 326 – Causing grievous hurt by dangerous weapons or means (including poisoning) • 328 – causing hurt to commit an offence
Drugs causing tachycardia • Alcohol • Datura • Nicotine Bradycardia Aconite Digitalis Opiates Organophophates
Duties of Medical Practitioner • Private practitioners are bound to inform the police in case of homicidal poisoning • In suicidal and accidental-If the person dies • If private practitioner is summoned by the investigative police officer, he is bound to divulge all information • Govt : medical practitioner – Has duty to inform all cases • Duty to arrange for Dying Declaration
General Lines of Treatment • Airway , Breathing, Circulation, Depressionof CNS(correction) Decontamination/Dextrose/Drugs • Removal of unabsorbed poisons: • Inhaled poisons: Fresh air • Injected poisons: Ligature application • Contact poisons: Immediate removal of clothing and washing thoroughly • Ingested poisons: Gastric Lavage
Gastrointestinal decontamination • Gastric Lavage (stomach wash) It is useful within 3 hrs of ingestion • salicylates,phenothiazymes,tricyclic antidepressants – (14 -16 hrs) • Ewald’s or Boas tube • Children – Ryle’s tube • Emesis
Gastric Lavage • 1cm diameter & 1 ½ meter long • Has got lateral openings or 30-40 French tube. • Middle portion has got a suction bulb • Other features are Mouth gag, 50 cm mark, etc. • 250 ml of Warm water is put over funnel of the tube and is taken out by the suction pump. • This washing is preserved for analysis • 1:5000 KmNO4 sol., 5% NaHCO3 sol. Or 4% Tannic acid 1 % sodium or potassium iodide is used for the lavage
Gastric Lavage • Patient position – left lateral ,head dependent • Absolute CI is • Corrosive poisoning due to danger of perforation of stomach. (Exception: Carbolic Acid poisoning) • Convulsant poisons • Comatose patients • Volatile poisons • Esophageal varices • Hypothermia
Emesis: • It is useful within 3 hrs of ingestion • Done with ipecac syrup(30 ml) • Contraindications As in gastric lavage Severe heart disease Advanced Pregnancy
ADMINISTRATION OF ANTIDOTE • Activated Charcoal: Particles are small but with high absorptive capacity and it acts mechanically by adsorbing and retaining within its pores organic and some mineral poisons • Demulcents: These are substances which form a protective coating on the gastric mucous membrane and thus do not permit the poison to cause any damage • Examples include Milk, Starch, Egg white, Mineral oil, Milk of Magnesia, • Fats and oils should not be usedfor fat soluble poisons like, Kerosene, Phosphorus, OP compounds, DDT, Phenol, Acetone • Bulky Foods: They act as mechanical antidote to glass powder
Chemical Antidotes • They counteract the action of poison by forming harmless or insoluble compounds by oxidizing poisons • Common Salt: Decomposes Silver Nitrate by direct chemical action • Albumen: Precipitates Mercuric Chloride • Dialyzed Iron: Neutralize Arsenic poison
Physiological Antidotes: • These are substances which produce exactly the opposite actions to that of poison • e.g. atropine – PHYSOSTIGMINE • Strychnine - BARBITURATES
Chelating agents • These agents act by forming stable and soluble complexes by the inner ring structure which can combine with the METALLIC POISONS • e.g. British Anti Lewisite (BAL) and • Ethylene diamine tetra-acetic acid (EDTA)superior to BAL in Ars and Mercury • Penicillamine – maximum efficiency • Dmsa (succimer)superior in lead • DMPS • Desferroxamine- Acute iron poisoning
Universal Antidote • two parts activated charcoal, • one part tannic acid, • and one part magnesium oxide
ELIMINATION OF POISONS • URINARY ALKALIZATION: Aim for a Urinary pH of 7.5-8.5 Indications: poisoning with chlorpropamide, phenobarbitone, salicylates, phenoxy acetate herbicides • WHOLE BOWEL IRRIGATION • Magnesium citrate • Sodium sulphate 30 gm. • Sorbitol 50 ml 0f 70% solution • polyethyleneglycol • Extracorporeal techniques: HEMODIALYSIS: • Multiple-dose activated charcoal: This can increase elimination of some drugs by interrupting their enteroenteric & enterohepatic circulation • PERITONEAL DIALYSIS • CHARCOAL HAAEMOPERFUSION
Routine viscera to be preserved • Liver • Kidney • Stomach • Small intestine • Blood • Urine
COMA COCKTAIL • Dextrose – 100ml of 50% solution • Thiamine – 100mg • Naloxone - 2mg • UNIVERSAL ANTIDOTE
CORROSIVES • Corrosives are the poisons that fixes, destroys and corrodes tissues • Concentrated acids: • Mineral acids, eg. Sulphuric acid, Hcl, HNo3 • • Organic acids, eg. Carbolic acid, Oxalic acid • Concentrated alkalies • eg. Caustic potash, NaOH, KOH etc. • sulphuric acid - (oil of vitriol)
CORROSIVES • Teeth chalky white – sulphuric acid • Perforation of stomach common – sulphuric acid • Stomach has consistency of wet blotting paper – sulphuric acid • Crowns of teeth yellow – nitric acid • xanthoproteic reaction – nitric acid • Pupils dilated • Fatal dose 10-15ml • HCl 15-20ml • Give nothing by mouth
Can give demulsants Do not neutralise with strong alkalies Do not give bicarbonate - CO2 gas - risk of perforation Corroded areas brown or black,HCl - gray VITRIOLAGE Throwing of sulphuric acid to face – jealousy or revenge Grievous hurt
OXALIC ACID • acid of sugar, salt of sorrel Colourless, transparent prismatic crystals, Natural constituent of plants eg spinach • FATAL DOSE : 15‐20 gm FATAL PERIOD: 1‐2 Hrs • Do not loose poisonous property even when diluted • VOMIT usually contains altered blood with mucous and HAS A COFFEE GROUND APPEARANCE • Hypocalcaemia • Signs of TETANY
OXALIC ACID • Fulminant poisoning • Uraemia-oxalate crystals in renal tubules • Metabolic acidosis, VF • TREATMENT • Stomach wash– Ca lactate, Ca gluconate ( antidote is any prep of Ca • Ca gluconate 10%, 10ml i.v
CARBOLIC ACID • CARBOLIC ACID ( phenol) • Colourless, prismatic, needle like crystals, with burning sweet taste with carbolic/ phenolic smell • FATAL DOSE : 10‐15 gmFATAL PERIOD: 03 TO 04 Hrs • S/S Poisoning is called CARBOLISM • Corroded mucosa appears whitish, lips , mouth and tongue corroded WHITE AND HARDENED • CARBOLURIA - Urine is colourless to slight green at first but turns green or even black on exposure to air. • Phenol is partly oxidisedTO HYDROQUINONE AND PYROCATECHOL, The further oxidation of Hydroquinone and pyrocatechol in the urine is the cause of green coloration
CARBOLIC ACID • CHRONIC POISONING ( Phenol marasmus) • OOCHRONOSIS pigmentation of skin and cornea and cartilages • CAUSTIC ALKALIES • Effect esophagus> gastric mucosa • So STRICTURE FORMATION MUCH MORE COMMON with alkalies then with acids • OH‐ ion cause saponification of fats • LIQUIFACTIVE NECROSIS
CAUSTIC ALKALIES • FATAL DOSE: • NaOH, KOH: 5 gm • Potassium carbonate: 18 gm • • Sodium carbonate: 30 gm • Ammonia: 5‐10 ml • • FATAL PERIOD: Usually 24 Hrs
Abrus Precatorius Indian Liquorice Active principle: – ABRIN ( toxic protein that disables ribosomes, inhibits protein synthesis, antigenic properties, hemolytic properties) ABRINE- an amino acid; haemagglutinin, ABRALIN- a glycoside F.D. : 1 SEED F.P. : 3- 5 DAYS SUI’S – Needles – cattle poisoning, rarely for homicide. Resembles VIPERINE SNAKE BITE. TREATMENT :Anti abrin
RICINUS COMMUNIS (CASTOR, ARANDI) Active principle: • ToxalbuminRICIN, a water soluble glycoprotein F.D. : 10- 20 seeds F.P. : 3-5 days Treatment: • Gastric lavage • Emetics and demulscents • symptomatic
Calotropis gigantea/ calotropis procera madar or akdo • Active principle: uscharin, calotoxin, calactin, calotropin (cardiac glycoside) and gigantin (contained in serum) • Medico- legal importance • • Madar juice is commonly used as an ABORTIFACIENT, • May be used for homicide , suicide or infanticide • ANIMAL POISON • ARTIFICIAL BRUISE • ARROW POISON
DELIRIANT POISONS • Datura • Atropa belladonna • Hyoscyamusniger • Cannabis indica • Cocaine
Datura • Active principle contains alkaloids: • hyoscyamine • hyoscine or scopolamine • Traces of atropine
Datura • Earliest symptom: Bitter taste in mouth Inhibition of salivation: Dryness of mouth and throat (dry as a bone) • Difficulty in talking • Dysphagia • Unquenchable thirst • Dilatation of cutaneous blood vessels • Face is flushed (red as a beet) • Pupils: Dilated • Insensitive to light Power of accommodation near vision paralyzed (Blind as a bat) • Inhibition of sweat secretion & stimulation of heat regulating center: Body temp. raised • Skin dry and hot (hot as a hare) Vomiting , Giddiness, unsteady gait (drunken individual) • Initially restless and confused Later delirious, mutters indistinct words (mad as a wet hen)
Datura • FATAL DOSE & FATAL PERIOD • Seeds: 100 to 125 • Alkaloids: 60 mg (Adult) 4 mg (Children) • Death occurs within 24 hours • ML IMPORTANCE • ROAD POISON – stupefying persons for robbery, rape etc • Antidote - physostigmine
coccaine • a colorless ,odorless, crystalline ALKALOID with better taste • prepared from the LEAVES of THE ERYTHROXYLON COCA PLANT • Crack. White lady, snow • Route of Administration Cocaine can be administered as a drug of abuse in the following ways • Cocaine hydrochloride Snorting (intranasal) Intravenous injection • ingestion
cocaine • Hyperthermia – cocaine fever • Amotivational syndrome • Chronic cocaine poisoning • Black tongue • COCAINE BUGS – MAGNAN’S BUGS –sensation of grains of sand under skin • SPEEDBALL – Combination OF COCAINE AND HEROIN - injected • BROMPTONS COCKTAIL-mixture of cocaine + morphine (heroin) + chlorpromazine+alcohol,earlier used for pain management in terminal illnes like cancer.
Cannabis indica/sativa • Common Names :Indian hemp or cannabis sativa in India • THC – major psychoactive ingredient in the marijuana plant • cannibinol and cannbidiol also components but less present in plants • Names: marijuana, hashish, charas, bhang, ganja, sinsemilla • BHANGLeast potent form Also called siddhi, patti, sabji • Prepared from dried leaves & fruit shoots
Cannabis indica/sativa • Mildest and contains 15% of active principle • MAJOON : Sweet prepared with bhang • GANJA Consists of flowering tops of the female plant It is mixed with tobacco and smoked in pipe • Contains active principle in conc. of 25% • MARIHUANA OR MARIJUANA Common names are pot, grass tea, Mary Jane • Smoked in pipe or rolled in cigarette called REEFERS OR WEED
Cannabis indica/sativa • CHARAS OR HASHISH • Resin exuding from leaves and stems • Dark green or brown color • Smoked with tobacco in a pipe ‘hookah’ • Active principle is in con of 25- 40% • It is the most powerful of all cannabis preparations
Cannabis indica/sativa • RUN AMOK :It is a psychotic disturbance caused by the continued use or even first time use of cannabis • It is characterized by a frenzied desire of the person to commit murders • He first kills a person against whom he may have real or imaginary enmity and then kills anyone who comes in his way until the homicidal tendency lasts. • Then he may commit suicide or surrender himself.