Phosphorus

There are 2 varieties.
1} White phosphorus- It is highly poisonous, crystalline, waxy, translucent, soluble in organic solvents, has a garlicky smell, is luminous in the dark {phosphorescence}, ignites at 30 degree centigrade, emits fumes of phosphorus trioxide on exposure to air. It is stored under water or kerosene. It is used in fertilisers, insecticides, rodenticides, incendiary bombs, smoke screens, fireworks, etc. It should never be touched with fingers.
2} Red phosphorus- It is granular with no taste or smell, non-luminous, non-toxic.

Route :
Ingestion
Fatal Dose :
60-120 mg
Fatal Period :
2-8 days.
Mechanism of action :
1} In Acute poisoning- acts as a protoplasmic poison. It causes hepatic dysfunction {hepatotoxicity} resembling ischaemia- known as necrobiosis. This results in disturbance in carbohydrate and fat metabolism.
• Inhibition of deposition of glycogen
• Increased deposition of fat
2} In Chronic poisoning- there is excessive bone formation at the epiphyseal end leading to necrosis and sequestration.
3} Phosphine {PH3} gas leads mainly to respiratory manifestations

Clinical Picture :
1. Fulminating poisoning – This is seen when more than one gram is taken. These patients usually die within twelve hours due to shock and cardiovascular collapse because phosphorus has a direct action on the heart and blood vessels. Those who survive more than 12 hours are restless, delirious and some maniacal before death. Thirst, severe nausea, vomiting and retching occur.
2. Acute Poisoning
A. First Stage – Due to local irritation, symptoms occur within a few minutes to a few hours after exposure and last from 8 hours to 3 days. Ingestion produces burning pain in the throat and abdomen, with intense thirst, nausea, vomiting, diarrhoea, and severe abdominal pain. Breath and excreta have garlic like odour. Luminescent vomit and faeces are diagnostic. Skin contact produces painful penetrating second and third degree burns which heal slowly.
B. Second Stage – This is a symptom free period lasting 2-3 days.
C. Third Stage – Symptoms of systemic toxicity occur from absorbed poison. There is nausea, vomiting, diarrhoea, haematemesis, liver tenderness and enlargement, jaundice and pruritis. Haemorrhages occur into the skin, mucous membrane and viscera, due to injury of blood vessels and inhibition of blood clotting. Renal damage results in oliguria, haematuria, casts, albuminuria and sometimes anuria. Involvement of CNS causes convulsions, delirium and coma. Death may result from shock, hepatic failure, CNS damage, haematemesis or renal insufficiency.
There is priapism {painful persistent erection of the penis}.

Chronic Poisoning:
The frequent inhalation of fumes over a period of years causes necrosis of the lower jaw in the region of a decayed tooth. At first there is toothache, which is followed by swelling of the jaw, loosening of the teeth, necrosis of the gums, and sequestration of bone in the mandible. This condition is known as ‘phossy jaw’ {glass jaw} in which osteomyelitis and necrosis of the jaw occurs, with multiple sinuses discharging foul-smelling pus.
The systemic symptoms are nausea , vomiting, anorexia, pain in the stomach, indigestion, purging, pain in the joints, loss of weight, bronchitis, jaundice and anaemia. Spontaneous fractures may occur.

Treatment :
1} Gastric lavage using 1:5000 solution of potassium permanganate oxidises phosphorus to phosphoric acid and phosphates which are harmless.
2} Activated charcoal adsorbs the poison.
3} Stomach can be washed with 0.2 percent copper sulphate solution or} or 0.2 g. of copper sulphate may be given every 5 minutes until vomiting occurs. It coats the particles of phosphorus with a film of copper phosphide which is relatively harmless. As it has caustic properties and can cause acute copper poisoning, care has to be taken.
4} Vitamin K, 20 mg. i.v. in repeated doses to combat hypoprothrombinaemia or blood transfusion.
5} The bowel should be evacuated with magnesium sulphate.
6} Wash out the bowel and repeat at intervals for several days.
7} Oils and fats should be avoided as they dissolve phosphorus and promote absorption.
8} Transfusion of glucose-saline and plasma with vitamins and noradrenaline is useful to protect the liver and correct shock and dehydration.
9} If renal failure is severe, peritoneal or haemodialysis may be required.
10} Burns should be thoroughly washed with 1 percent copper sulphate solution in water.

Chronic Poisoning-
1. Regular dental check-ups.
2. Carious teeth should be filled in or extracted.
3. Regular mouth washes with sodium bicarbonate.
4. Periodic X-ray examination of the jaws.

Phosphorus

Home

Partner Sites