A retrospective analysis between 2001 and 2009 has shown that a little more than half of the victims of Bhopal gas tragedy suffer from abnormal lung function.
The study conducted by Sajal De at Bhopal Memorial Hospital and Research Centre, which has been published in February 2012 issue of the Indian Journal of Medical Research of the Indian Council of Medical Research showed that people who were exposed to the gas leak in 1984 still have considerably greater risk of developing obstructive pattern with relative risk being between 1.33 to 1.45 among the victims compared to non victims.
In the study, lung function test (spirometry) records of a total of 4782 gas victims and 1190 non-gas exposed individuals were analyzed. Obstructive pattern was observed in 50.8 percent of the victims among whom 51.8 percent were suffering from severe to very severe obstruction while about 29 percent were found to suffer from mild obstruction.
The spirometry test measures the amount and speed of air inhaled and exhaled to evaluate the capacity of the lungs. Obstructed spirometry tests indicate narrowing of airways, and are commonly associated with lung diseases like asthma and Chronic Obstructive Pulmonary Disease (COPD).
The study also suggests that the incidence and severity of obstruction among the surviving gas victims has increased with time and they were found to be at higher risk of developing obstructive lung disease irrespective of their age.
The 10-year-study in Bhopal has found that every second person that was exposed to the gas leak 28 years ago has abnormal lung function. The study shows that people exposed to the methyl Isocyanate leak have a nearly 30 per cent higher chance of contracting lung disease than the unexposed population.
While subjects’ ages ranged from 10 to 60, data indicated the highest relative abnormalities from 20-29. “So, the gas victims who were infants at the time of the disaster were possibly more affected by the residual fibrotic changes in lung,” states the study.
The study does not ignore other external factors that could be at the root for lung diseases. The study cautions that smoking habits among the young adults exposed to the gas could also have had an impact on the findings.