The butler did it and the doodhwala was an eager accomplice—but like a cheap Byomkesh clone sold on Howrah sidewalks, the devil was in the telling. The unfolding of a befuddling Bengalee murder mystery when the thievish fox walked into the snare for the wolf. All along, the choice of poison was arsenic, less than one-eighth of a teaspoon of which can kill a healthy adult. Ingesting the toxin in small quantities for a prolonged period causes arsenicosis, cancer. Kills slowly, leads to horrible death. And arsenic has been a silent killer prowling Bengal, like the sneaky butler of detective pulp. That’s no fiction, but a grim fact that a group of researchers at Jadavpur University went after. And so it happened: the study on groundwater arsenic contaminating groceries and dairy in West Bengal upheld the obvious fear (that our food is laced with the toxin) and also confirmed a long-held doubt that the milkman is bilking the folks by watering down his cans from the tap, hand pump, well, pond, whatever. Cow milk in containers of milkmen had more arsenic concentration than in samples collected in the source—freshly-milked in dairies or at homes of cattle farmers. The researchers attributed the increased toxicity to the milkmen’s incorrigible habit of “mixing water in raw milk to increase the volume” and bump up their margin. Elementary Babumoshai, the milkman does it!
Now for more macabre facts for doomscrollers: the latest study found that cattle in areas having arsenic-contaminated groundwater have more than four times higher intake of the toxin than those in unaffected places. Milk from cows feeding on contaminated water and fodder has arsenic much above the stipulated safe level. That arsenic poisoning is spreading to unaffected areas because of rampant groundwater use in farming, in animal husbandry and in aquifers for pisciculture. That arsenic has seeped into staples such as rice, vegetables, milk and animal meat. The tainted grains and greens have been exposing a larger population to arsenic poisoning.
Previous studies have already declared Bengal as India’s worst-affected state. The Bengal Delta, including Bangladesh, has often been called the site of “largest mass poisoning in human history” due to groundwater contamination. According to a recent IIT Kharagpur publication, 28 million people in Bengal are exposed to arsenic-laced groundwater—roughly one-third of the national total of 90 million. Of the state’s 341 community development blocks, 148 in 14 districts have groundwater arsenic contamination above the permissible limit of 10 microgram a litre. Of them, 129 blocks in central-south Bengal had levels higher than 50 micrograms, while at some places, it’s 100 to 300 times higher than the WHO standards.
But I drink treated water from the river? A large population gets arsenic-free drinking water, but there has been no restriction to extracting groundwater in the state. This very groundwater irrigates the fields, seeps into the rice grains, and travels into your stomach—one spoonful of Basonti pulao at a time. “If people continue to eat food produced in arsenic-hit areas, in another five to 10 years, we will get cases of arsenicosis in non-affected areas as well,” says Tarit Roy Chowdhury, professor at the School of Environmental Studies, Jadavpur University. He is the co-author of Arsenic Toxicity in Livestock Growing in Arsenic Endemic and Control Sites of West Bengal: Risk for Human and Environment, a report published in scientific journal <> this January. The report says, “A considerable amount of arsenic has been observed in animal proteins such as cow milk, boiled egg yolk, albumen, liver and meat from exposed livestock” and the risk follows this order: drinking water, rice grain, cow milk, chicken, egg, mutton. Adults are more likely to have cancer from these foods. Hundreds of people living in North 24-Parganas, the nation’s second-highest populated district, suffer from cancer, skin disease, irreversible fatigue and many more syndromes. Alok Sarkar, a South 24-Parganas resident, was the first arsenicosis patient detected in 1983. As many as 17 members of his family were diagnosed with cancer and none lived. Many households have lost someone, or have a sick member; several families have been uprooted for good, out of fear or after the death of the sole earner.
But there’s no escaping the killer. “There is no doubt that arsenic is reaching non-affected areas through the food chain. All we need to know is the extent to which arsenic poisoning is happening in the non-affected area,” says Abhijit Mukherjee, associate professor of geology and geophysics and co-author of the IIT Kharagpur paper, Occurrence, Predictors and Hazards of Elevated Groundwater Arsenic Across India Through Field Observations and Regional-Scale AI-Based Modeling, published in the scientific journal <> in November 2020. The WHO’s safe limit for arsenic consumption is 3 micrograms per kg of body weight a day. A person weighing 50 kg can consume 150 micrograms a day without being affected. But if that person eats 300 grams of rice a day with 500 microgram a kg of arsenic concentration, the daily arsenic intake becomes 166 microgram. Add to that tainted milk, meat and vegetables. The Jadavpur University’s School of Environmental Studies had found 300 to 700 micrograms of arsenic a kg in rice sold in Calcutta.
Incidentally, Bengal’s arsenic hotbed is also its farming heartland—the districts of Malda, Murshidabad, Nadia, North 24-Parganas, South 24-Parganas, Howrah, Hooghly and East Burdwan sitting on the fertile, alluvial land of the lower-Gangetic plains. Livestock is a major income source, but the pasture is contaminated while paddy straw and rice husk fodders are too. “The effects remain undetected until they show visible signs, like on the skin. We have been demanding for long a complete ban on deep tube wells for farming. The state has plenty of surface water resources. We need to tap surface water for farming. There is no other way to prevent arsenic contamination through the food chain,” says Ashok Das, secretary of Arsenic Dushan Pratirodh Committee, an organisation against arsenic pollution.
Signs are subtle, no doubt. Almost 98 per cent students of a primary school in North 24-Parganas district had excessive iron in their urine, but they showed no physical symptoms. “Visible manifestation of the poisoning will show up a few years later. The diagnosis mentions cancers, but not what caused it,” says Das, ominous for a man whose organisation alone has counted 2,000 deaths from arsenic poisoning.
By Snigdhendu Bhattacharya in Calcutta
