• Pure metallic copper is not poisonous but many salts of copper are poisonous.
• Copper sulphate produce toxicity and it is strong irritants to skin and mucous membranes.
• Anhydrous copper sulphate is a white powder
• It crystallizes with water to give blue colour.
• Copper sulphate is frequently used in industry as well as horticulture.
• It is used as a disinfectant or bactericide for water treatment.
• It is used as medicine as an emetic and also as a several intrauterine contraceptive devices.
• It is also is used as a fungicide, molluscicide and wood preservative.
• Copper sulphate is used as an insecticide spray in vineyards.
• It is used as algaecide as a mordant in leather tanning.
• It is also used as laboratory agent.
• It is taken through the mouth either in pure form or mixed with food.
• It can also administered through the vagina, rectum, abraded surface and by injection.
• The administered of the poison is rarely homicidal.
• Accidental and suicidal intakes are comparatively more frequent.
The fatal dose of copper sulphate is 30gm.
The fatal period of copper sulphate is 1 to 3 days
Absorption, Metabolism and Excretion
• Copper is normal constituent of body and normal content is 150 mg. It is present in two forms – bound with albumin and other form bound with copper enzyme ceruloplsmin.
• Copper is absorbed through skin, GIT, lungs and mucous membrane.
• It is excreted through bile and traces are found in saliva and milk.
Mode of Action
• As a biocide, copper is an essential nutrient for many organisms.
• It acts as a cofactor in respiration, and therefore copper is required for aerobic metabolism.
• Accumulation of copper ions or intracellular release of free copper ions from proteins leads to cell damage.
• Then, Copper catalyzes reactions that result in the production of hydroxyl radicals through the Fenton and Haber-Weiss reactions.
• The highly reactive oxygen intermediates lead to lipid peroxidation and oxidation of proteins. Free copper ions oxidize sulfhydryl groups, such as cysteine, in proteins or the cellular redox buffer glutathione. Similarly, copper ions inactivate proteins by damaging Fe-S clusters in cytoplasmic hydratases.
Sign and Symptoms
• Metallic taste
• Burning sensation in the stomach.
• Salivation, thirst and nausea.
• Convulsion and paralysis in some cases.
• Increased salivation
• Colicky abdominal pain
• Nausea and vomiting- Vomitus is bluish or greenish in color.
• Liver tenderness
• Increased levels of transaminase may occur.
• Oliguria and renal failure
Inhalation of Copper Fumes or Dust Causes
• Respiratory tract irritation
• Sore throat
• Corneal ulceration
• Chacosis lentis
• palpebral oedema
• Metal fume fever.
• Abdominal pain
• Greenish line on dental margins of gum (Clapton’s line).
• Vineyard Sprayer’s lung disease
• Greenish hair discolouration
• Wilson’s disease
• Serum caeruloplasmin level – A value of 35 mg% or less at 24 hours is associated with serious toxicity.
• Blood copper level – If this is elevated beyond 1.5 mg/100 ml, there is likelihood of serious toxicity. Average normal levels are 1.09 mg/L for men, 1.20 mg/L for non-pregnant women and 2.39 mg/L for pregnant women.
• Urine level – Normal daily excretion of copper in the urine is less than 0.6 micromole/day.
• Radiography – Metallic copper is radiopaque. X-rays may be useful to establish diagnosis. Copper salts are not considered radiopaque.
• Haemodialysis is said to be useful in the early stages of poisoning when the metal is still circulating in the bloodstream as free copper.
• Administration of egg white or milk orally may help in detoxifying copper resulting in the formation of an albuminate.
• Stomach wash can be done with a solution of potassium ferrocyanide. It converts the copper salt (especially copper sulfate) into insoluble cupric ferrocyanide.
• Induction of emesis is contraindicated.
• D-penicillamine is generally recommended drug for Wilson’s disease, a condition of chronic copper overload. Chelation therapy is generally considered in symptomatic patients.
• Dimercaprol and Calcium disodium edetate has been used in patients with acute copper sulfate intoxication.
• Symptomatic measure has been administered such as antacids and ranitidine for prevention of gastric erosions, dopamine for shock, etc.
• For Eye exposure-
► Remove contact lenses and irrigate exposed eyes with copious amounts of room temperature with 0.9% saline or water for at least 15 minutes.
► If irritation, pain, swelling, lacrimation, or photophobia persists after 15 minutes of irrigation, an ophthalmologic examination should be performed.
• For Dermal exposure-
► Remove contaminated clothing and wash exposed area extremely thoroughly with soap and water.
► Chelation therapy should be considered if copper concentrations are excessive.
• For hair colour exposure then use shampoos containing penicillamine (250 mg in 5 ml of water and 5 ml of shampoo) or EDTA have been effective in removing green colour from hair due to copper exposure.
Post mortem Findings.
• Greenish blue froth at mouth.
• Mucous membrane of alimentary canal is inflamed and ulcerated.
• Copper may be found deposited inside.
• Bluish line on gums.
• Greenish or bluish stomach contents and gastric mucosa.
• Kidneys cause tubular necrosis, edema of medulla and appearance of eosinophilic cast.
• Muscle atrophy
• Liver become soft and fatty.
• Microscopy shows centrilobular necrosis.
Medico legal Aspects
• Suicidal cases are common.
• Accidental poisoning may occur in children.
• Chronic poisoning may caused due to industrial hazard.
• Use to procure criminal abortion.
• Cattle poison has been reported.
• Homicidal cases are rare, but have been also reported.
• By incinerating the suspected toxicological materials in an electric furnace at 550 degree Celsius.
• By wet oxidation method with sulphuric and nitric acids.
Detection and Forensic Examination
• Copper sulphate gives black precipitate in acidic medium with hydrogen sulphide.
• If copper sulphate is present then on treating with potassium ferrocyanide solution gives chocolate brown precipitate with copper salts in acetic acid medium.
• An acidic solution containing copper salt deposits copper on an iron wire which is indicator of copper sulphate.
• Spectrograpghy gives reliable results.
• It is estimated spectrographically.
• Colorimetrically- Sodium diethldithiocarbonate forms a complex with copper which is soluble in amyl alcohol. It is estimated with a colorimeter from the solution.
• Iodometric titration also gives reliable results.
• Stomach washings
• Stomach contents
• Dr. K.S. Narayan Reddy. The essential of forensic medicine and toxicology.34th edition.
• VV Pillay. Modern medical toxicology.4th edition.
• R.K.Sharma. Concise textbook of forensic medicine and toxicology. 3rd edition.