A host of health issues associated with the 1984 Bhopal Gas Tragedy continue to haunt generations that are not directly exposed to the toxic gas, according to a new study.
Nearly four decades after the tragedy that claimed at least 30,000 lives, future generations are afflicted by disabilities and cancer, the study published in journal BMJ One found.
The document, released on June 13, 2023, also noted a decline in male births in 1985, a year after the tragedy. The impacts are seen in a 100 km radius around Bhopal, affecting a more wider area than previously reported.
“These results indicate social costs stemming from the Bhopal gas disaster that extend far beyond the mortality and morbidity experienced in the immediate aftermath,” the researchers said in a statement.
The toxic methyl isocyanate gas that leaked out of the Union Carbide pesticide plant near Bhopal spread to a 7 km radius around the plant. It exposed more than half a million people and resulted in up to 30,000 deaths in the region.
The survivors suffered from respiratory, neurological, musculoskeletal, ophthalmic and endocrine issues. There was a four-fold increase in miscarriages and a higher risk of stillbirth and neonatal mortality (death within the first 28 days of life) following the tragedy. Even decades later, menstrual abnormalities and premature menopause have become common among exposed women and their offspring.
As the toxic gas affected the groundwater and the reproductive health of women exposed to the toxic gas, researchers from the University of California (UC) San Diego suspected that the health impacts could trickle down to future generations.
The team assessed the long-term health-related damages by gathering data from the National Family Health Survey (NFHS-4) conducted between 2015 and 2016 and the Integrated Public Use Microdata Series from India for the year 1999.
The latter, which presents harmonised data from the 1999 socio-economic survey conducted by the National Statistical Office, includes people from ages six to 64 years and those in utero (womb or uterus) at the time of the Bhopal Gas Tragedy.
Their analysis showed that women who were pregnant with a male foetus and lived within 100 km had one percentage point higher disability that affected their employment 15 years later.
Further, the proportion of males born dropped from 64 per cent from 1981-1984 to 60 per cent in 1985 if their mothers lived within 100 km of Bhopal. There was no change in the sex ratio beyond 100 km. The decrease in the male sex ratio could be explained by male foetuses being more vulnerable to external stress.
“Male foetuses are more susceptible to adverse shocks including smog, disease, natural disasters and stressful events during pregnancy,” Gordon McCord from the School of Global Policy and Strategy at UC San Diego and the author of the study, told Down To Earth.
This, he added, is due to developmental differences between male and female foetuses. Newborn girls are physiologically more developed than newborn boys.
Men born in 1985 within 100 km of Bhopal have an eightfold higher cancer risk than those born in 1976-1984 and 1986-1990.
Men born in 1985 and who continue to reside within 100 km of Bhopal suffered a 27-fold higher cancer risk in 2015 compared with those born in 1976-1984 and 1986-1990 and with those living more than 100 km from Bhopal.
Disabilities have robbed people of their ability to earn a living. Men who were in utero during the tragedy and who lived in districts within 100 km of Bhopal are one percentage point more likely to report employment disability compared with their older counterparts and those living further from Bhopal. This increases to two percentage points among those living within 50 km of the city.
The researchers further explained that the long-term consequences estimated in the study could be due to two effects. First is from direct exposure and second is the lack of mitigation of the effects through health, disability and education services.
Understanding the short-term and long-term damages caused by industrial disasters is key to gaining insight into the trade-offs involved in making regulatory decisions, the researchers wrote in their paper.
“On the one hand industrial growth creates jobs and economic development, and on the other, they introduce risks that industry and government need to manage through regulation,” McCord explained
It could also help policymakers dedicate resources to mitigate the harm caused by events or to calculate legal damages.
The results underscore the need for ongoing survivor support and robust regulatory protection, the researchers stressed.