Mercury Toxicity PDF

Heavy Metals Mercury Hg Hydrargyrum Toxicity Dr. Isam Elhassan Specialist of Forensic Medicine & Clinical Toxicology  Mercury Sources: 1- Elemental (metalic): Hg vapour, dental amalgam, thermometers & sphygmomanometer Toxicity after inhalation only If swallowed it...

Heavy Metals Mercury Hg Hydrargyrum Toxicity Dr. Isam Elhassan Specialist of Forensic Medicine & Clinical Toxicology  Mercury Sources: 1- Elemental (metalic): Hg vapour, dental amalgam, thermometers & sphygmomanometer Toxicity after inhalation only If swallowed it is poorly absorbed 2- Inorganic salts: Calomel (mercurous chloride) insoluble purgative. Chronic mercury Poisoning in children exposed to mercurous chloride in teething lotions and diaper powders if absorbed it will result in pink teeth (Acrodynia) Which manifested by: Mercury Acrodynia: Insomnia, hypertension, peeling of skin, alopecia, pink and painful hands. Acute renal failure within 24hrs Mercuric chloride (HgCl2) >> disinfectant Mercurial fulminate >> percussion cap 3- Organic mercurial salts >> diuretics and fungicidal. Methyl mercury and ethyl mercury are well known as environmental contaminants that have been incorporated and concentrated in the aquatic food chain Mercury Mechanism of action: Mercury reacts with sulfhydryl (-SH) group resulting in depression of the cellular enzymatic mechanisms Elemental mercury vapor and organic mercurial compounds are particularly toxic to the CNS, while inorganic mercuric salts are corrosive and nephrotoxic Mercury Acute mercury toxicity Clinical presentation: 1- GIT:  Metallic taste  Burning sensation from mouth to stomach  Nausea & blood tinged vomiting  Tenesmus [mercurial dysentery] >> diarrhea with mucus & blood  Dehydration & collapse Mercury Acute mercury toxicity Clinical presentation: 2- Renal:  Acute toxic glomerulonephritis >> oliguria with albumin and blood cast >> anuria & RF 3- Corrosive bronchitis >> pulmonary edema & nervous manifestations (tremors, & increased excitability) in exposure to mercury vapor Mercury Acute mercury toxicity Causes of death: 24 hours >> dehydration 10 days >> RF Mercury Acute mercury toxicity Treatment: 1. Remove from further exposure 2- Gastric lavage: using one of the local antidotes  Egg white & skimmed milk >> ppt of Hg albuminate  Sodium formaldehyde sulfoxylate >> reducing agent (HgCl2 >> HgCl insoluble) Mercury Chronic mercury toxicity “Mercurialism” Clinical presentation:  GIT Oral >> Salivation (an early sign) Gray line on the gum Gingivitis (swollen, painful, bleeding gingiva) loose teeth Gangrene (cancrum oris) Mercury Chronic mercury toxicity “Mercurialism” Clinical presentation:  GIT Intestinal >> Mercurial dysentery (diarrhea, mucus & blood)  Renal >> Albuminuria, hematuria granular and hyaline casts >> Oliguria & renal failure Mercury Chronic mercury toxicity “Mercurialism” Clinical presentation:  CNS: >> kinetic tremors (cerebellar affection)  Psychic: >> Hg erethism: shyness, loss of confidence, vague fears, depression (neurosis)  Skin >> Dermatitis  Eye: Mercurialentis (discoloration of capsule of eye lens) Mercury Chronic mercury toxicity “Mercurialism” Treatment: I. Prophylactic treatment:  periodic medical examinations of exposed workers  proper exhaust ventilation, dust filters, protective clothing, masks, gloves and boots  Intake of proper amounts of Ca, Zn & Fe Mercury Chronic mercury toxicity “Mercurialism” Treatment: II. Curative treatment: 1. Stop further exposure 2. Physiological antidotes (Chelation therapy): o D-penicillamine o BAL & its oral analogues DMSA & DMPS 3. Symptomatic  Mouth hygiene  Tranquilizers  Atropine >> salivation  Na hyposulphite for dermatitis Thank you