Toxicology Pesticides - Abbas Arafa

Toxicology Pesticides Abbas Arafa  Agenda OPS Rodenticides Chloride Pyrethrines and pyrethroids Inhibit A.CH esterase by phosphorylation → accum. of A.Ch → toxicity. -OP-A.ChE bond may become permanent if antidote not...

Toxicology Pesticides Abbas Arafa  Agenda OPS Rodenticides Chloride Pyrethrines and pyrethroids Inhibit A.CH esterase by phosphorylation → accum. of A.Ch → toxicity. -OP-A.ChE bond may become permanent if antidote not administrated within 24-36h (known as aging). - The irreversible bond is d.t diethyl group leaves the phosphate. ‫م‬  ECG : Initial sinus tachycardia & HB Chest radiograph : pulmonary edema & bronchospasm. Occupational exposure Electrolytes : hypokalemia & hyperglycemia. Epidemic “contaminated food” CBC : leukocytosis. History : Investigation: Urine analysis : proteinuria and glycosuria Miosis with muscle fasiculations → most frequent. cholinesterase Garlic like odor of breath Physical Anxiety and diaphoresis ,V , D Toxin specific levels examination : Tachycardia and salivation. test:  Stabilization 1. Intubation & suction 2. O2 inhalation (100% for 1-2 H) then 70%. Decontamination Antidotal therapy Atropine Stop when pupil dilated??? Stop when lung become dry??? seizures : diazepam. Symptomatic ttt Hypotension: normal saline. Pulmonary edema : bronchospasm → O2 intubation  Bleeding 1) Highly toxic :thalium, strychnine, arsenic. General ch.ch 2) Moderately toxic : α naphthyl – thiourea and cholecalcefrol ( Vit D3 ). (Classification): 3) Low toxicity : warfarin anti coagulant. Mechanism : # synthesis of vit k → # of blood clotting factors ( 1972 ) II. VII, IX, X. Treatment : 1) Activated charcoal. 2) Oral Vit K1 : 5 mg in children and 20 mg in adult repeated 2-4 times daily. 3) Fresh frozen plasma ( FFP ) and activated factor VII Zinc phosphide: inorganic, dark crystalline powder, water insoluble with rotten fish or phosphorus odor. Mechanism of toxicity : zink sulphide phosphine gas (Cytochrome C oxidase inhibitor) → cellular toxicity and necrosis of GIT and injury to liver and kidney and lung if inhaled. treatment of zinc 1) CNS : headach ataxia seizures and coma. 2)GIT : nausea, vomiting ( black vomitus ) rotten fish phosphide toxicity : odor of breath. 3) Hepatic : centrilobular necrosis and jaundice 1- Mostly supportive and 4) Skeletal MS :parasythesia and intention tremors. symptomatic. CL/p : 5) Metabolic acidosis , hypocalcaemia and tetany. 6) Heart : shock and dysrhythmia. 7) Ocular diplopia. 2- Dilution by water, milk or NaHCO3 is used.