N.B. Nair
Kolkata (ISJ): An eminent environmental scientist at the Jadavpur University in West Bengal has warned, if an effective strategy is not adopted, arsenic and fluoride contamination could pose a serious health threat to people living in the Gangetic-Brahmaputra plains of India. Dr. Tarit Roychowdhury, senior faculty member and scientist of the School of Environmental Studies at the University said, the situation in West Bengal is the worst in terms of arsenic contamination.
Dr. Roychowdhury explained, earlier exposure to arsenic and fluoride was only through the consumption of drinking water (groundwater); however, now both these contaminants enter the human body through the food chain due to the use of contaminated groundwater for agriculture and livestock, especially during the summer season.
“The most dangerous thing is arsenic contamination through rice grain, which is the staple crop of India. Whatever we consume now – rice, pulses, and vegetables is contaminated by arsenic and fluoride. Both the contaminants affect our internal body system,” said Dr. Roychowdhury, who has been extensively involved in the research study of arsenic water contamination issues in of West Bengal and other parts of India for the last 25 years.
The problem was first time identified in 1989 and later, the magnitude of contamination extended rapidly. Fourteen districts of West Bengal are highly and five more are moderately arsenic contaminated. Arsenic is toxic and carcinogenic; whereas fluoride is toxic in character whenever the elements cross their dietary recommended values, prescribed by World Health Organization (WHO). Fluoride is not carcinogenic but toxic. Fluoride can attack the calcium in the body like teeth and bone. It can just bristle the bones,” he added.
Dr. Roychowdhury lamented, he had shared the outcome of research all these years with the West Bengal government and the federal government through its research organisations. Instead of taking serious note of the findings of the scientists, the state government initially did not take note of these burning health issues and denied their existence. However, later they accepted it, though no effective mitigation strategies were adopted to overcome the problem as per the actual demand.
Dr. Roychowdhury cited dense population, illiteracy, and poverty as major reasons for the continued use of contaminated groundwater. The scientist suggested a few alternative ways like rainwater harvesting and surface water treatment as a permanent solution to these contaminations.
“Arsenic contamination is purely geogenic in this part of India. It is related to the Ganges River. The magnitude of the arsenic calamity, if you follow the map, is not limited to West Bengal, but it is extended to other states like the Kanpur-Allahabad track in Uttar Pradesh and upstream in Uttarakhand, Bihar, and Jharkhand. The entire Gangetic plains in India and later in Bangladesh, where it is known as Padma, the Meghna River belt also in that country and the Brahmaputra belt in North East hill states are affected. So, the entire Gangetic-Meghna-Brahmaputra plains are affected,” explained Dr. Roychowdhury.
According to the scientist, the removal of arsenic from drinking water is not the best alternative strategy. The best alternative system is surface water treatment, water recharge, and rainwater harvesting. A deep aquifer is comparatively safer in the depth zone of 700-1000 ft. However, in many geographic zones, arsenic was found even under deeper zones.
In another study published in the latest recent edition of Elsevier Journal, Dr. Roychowdhury and his team found “arsenic contaminated dietary intake in daily routine can bring serious health hazards in children.”
“Arsenic toxicity can eventually lead to future cancer risk which is sub-clinically manifested through biological samples mainly keratin tissues along with the formation of micronuclei in urine epithelial cells of the affected children, compared to apparently control area children,” the study further noted.
The geochemical arsenic toxicity affects domestic livestock and through them, humans, and the environment. The daily dietary intake of an exposed adult cow or bull was found to be 4.56 percent higher than the controlled populace and about 3.56 times higher in exposed goats.
“A considerable amount of arsenic has been observed in animal proteins such as cow milk, boiled egg yolk, albumen, liver, and meat from the exposed livestock. Cow milk arsenic is mostly accumulated in casein (83 percent) due to the presence of phosphoserine units,” reveals one of their studies.
The most regularly consumed foodstuff in the region shows the human health risk in a distinct order – drinking water, rice grain, cow milk, chicken, egg, and mutton ranging from risk class 5 to 1 (as per SAMOE risk thermometer). The health risk assessment model reveals more risk in adults than in children, subsisting severe cancer risk from the foodstuffs where the edible animal proteins cannot be ignored.
The study suggested, that domestic livestock should be urgently treated with surface water, while the provision of both arsenic-free drinking water and nutritional supplements made mandatory for the affected human population to overcome the severe arsenic crisis.
Image courtesy: Dr. Tarit Roychowdhury
