No higher occurence of cancer due to radiation.
Amidst protest against nuclear power projects on the grounds of exposure to high levels of radiation causing cancer and deformities, the state-run Nuclear Power Corporation (NPC) revealed that the radiation dose to the public from Indian nuclear plants was insignificant compared to the natural background and the seasonal variations in natural background at any place.
To substantiate its argument, NPC brought out a 54-page analysis of health profile of its employees from its 20 operating plants with a generation capacity of 4,780 MW during 1995-2010. The report said the cancer average incidence rates and average death rates in males, females and combined population (both sexes) was less than the respective national rates in each category.
Of the total 80 cancer cases, 41 were from among radiation workers and 39 from non-radiation workers. The average incidence rate was reported at 55.73 per cent against the national incidence rate of 92.9 per cent measured for the average total population of 8,634 (males) during 1995-2010. The average death rate was reported at 29.67 per cent when compared to national death rate of 71.2 per cent.
“This proves that there is no additional risk to employees developing cancers by virtue of their working in radiation areas,” noted Dr R Deolalikar, certifying surgeon at NPC's Narora plant. He opined that the workers in NPC operating sites do not show any variation in disease pattern and their prevalence was far less than that seen in the general public. He, however, made it clear that in all the 80 cases of cancer deaths it was not necessary that the disease was the immediate cause of death. All the radiation workers were in receipt of doses within the regulatory limits and the life cumulative dose was in the range of 0.88 micro sieverts to maximum 663.15 micro sieverts.
HR Bhat, chief engineer (health physics), said radiation was a part of nature. "Compared to the average natural radiation background dose of 2,400 micro sieverts (Sv/y) per year the radiation dose from Indian nuclear power plants during 2010 was 0.42 to 39.6 micro Sv to the persons near plant boundaries."
He explained that Karunagappally taluk in costal Kerala has radiation background up to 70,000 micro Gy/y due to the deposits of thorium in the sand, and studies on the people of the area have shown no higher occurrence of cancer.
RA Badwe, director, Tata Memorial Centre, said the highest incidence of radiation exposure was reported from northeast India where there are no nuclear reactors. Such incidence in Mumbai, Chennai, Bangalore, Ahmadabad and Delhi (cities with one or more nuclear reactors) was quite similar to other metropolitan cities with no reactors.
NPC executive director N Nagaich said there was a population of nearly 100,000 living in high radiation areas of Kerala and Tamil Nadu. Some of these people receive exposures 10 times more than the national average. However, there were no indications of harmful effects of radiation among this population. Radiation exposure to the population from nuclear power stations were in contrast, far lower, he added.
