The gas cloud was composed mainly of materials denser than the surrounding air. As a result it stayed close to the ground and spread outwards through the surrounding area. The initial effects of exposure were coughing, vomiting, severe eye irritation and a feeling of suffocation. People awakened by these symptoms fled away in shock from the plant.
Those who ran inhaled more than those who had a vehicle to ride. Owing to their height, children and other people of shorter stature inhaled higher concentrations. Many people were trampled to death in an attempt to escape.
Thousands of people had succumbed by the morning hours. There were mass funerals and mass cremations as well as disposal of bodies in the Narmada River. At least 170,000 people had to be treated at hospitals and temporary dispensaries.
The acute symptoms were burning in the respiratory tract and eyes, blepharospasm, breathlessness, stomach pains and vomiting. The causes of deaths were choking, reflexogenic circulatory collapse and pulmonary edema. Findings during autopsies revealed changes not only in the lungs but also cerebral edema, tubular necrosis of the kidneys, fatty degeneration of the liver and necrotizing enteritis.
The gas cloud toxic effects
The pollution caused in Bhopal gas tragedy is having serious consequences for the health and survival of the local population to this very day. Of the more than 200,000 persons exposed to the gas, the initial death toll within a week following the accident was over 2500. The stillbirth rate increased up to 300% and neonatal mortality rate by 200%. Estimates show that 100,000 to 200,000 people have permanent injuries. Most common reported symptoms were eye problems, respiratory difficulties, immune and neurological disorders, cardiac failure secondary to lung injury, female reproductive difficulties and birth defects among children born to affected women.
Environmental groups and Greenpeace claim the Union Carbide company left behind an industrial pollution of unknown radius. Although the contaminated area was partially cleaned up in 1996, the plant continued to poison the ground water that run to hand pumps in the same slums that suffered the brunt of the 1984 gas leak. In 1999 a soil study and water samples in and around the plant, scientists from the Greenpeace Research Laboratories at Britain's University of Exeter found overall contamination and hotspots of severe contamination with heavy metals and/or persistent organic pollutants. The list included an organochlorine which is a potent kidney toxin and suspected carcinogen as well as carbon tetrachloride at levels 1,700 times above the World Health Organization's limit for drinking water.