The study warned that, together, climate and occupational exposure are becoming silent yet powerful factors behind kidney decline in farming communities.
Published Nov 04, 2025 | 7:00 AM ⚊ Updated Nov 04, 2025 | 7:00 AM
Women working in a paddy field in Tamil Nadu. (iStock)
Synopsis: New research suggests that agricultural workers in Tamil Nadu, who work several hours under the sun, could be having silent damage to their kidneys. The researchers found early signs of kidney issues among the workers, while more than half of them had no underlying conditions, suggesting that long hours of outdoor labour in rising heat, coupled with dehydration, may be key drivers of the problem.
Under the blazing sun of Tamil Nadu’s farmlands, workers bend over paddy fields for hours, often with little rest and less water. Many of them return home drained, with their exhaustion dismissed as routine.
However, new research suggests that this daily strain may be leaving behind damage far more serious than fatigue; it could be silently harming their kidneys.
A recent study published in The Lancet Regional Health – Southeast Asia found that about one in 19 agricultural workers in Tamil Nadu shows signs of chronic kidney disease (CKD), and in nearly half the cases, doctors could not link it to diabetes or high blood pressure.
The findings raise unsettling questions about the role of extreme heat, dehydration, and harsh working conditions in rural India’s heartland. As scientists trace these patterns in the data, doctors and public health experts are beginning to see their echoes in clinics, among men and women whose livelihoods depend on labouring in an increasingly unforgiving climate.
The researchers screened nearly 4,000 adults in rural Tamil Nadu and found that about one in 19 agricultural workers showed early signs of CKD. More than half of them had no underlying conditions, suggesting that long hours of outdoor labour in rising heat, coupled with dehydration, may be key drivers of the problem.
Their findings pointed to a worrying trend — kidney damage emerging not from lifestyle disorders, but from the daily realities of rural work. Prolonged exposure to high temperatures, scarce access to clean drinking water, and limited rest during peak hours were among the main risks observed.
The study warned that, together, climate and occupational exposure are becoming silent yet powerful factors behind kidney decline in farming communities.
To prevent this, the research recommended simple but critical measures: Shaded rest areas, access to safe water, and regulated work-rest cycles during hot hours.
It also urged early screening for rural workers, noting that most cases remain invisible until the disease has already advanced. Strengthening local health systems to include regular kidney monitoring, the authors said, could help Tamil Nadu address what is fast becoming both a worker welfare and climate resilience challenge.
Doctors across southern India said the findings from the study in Tamil Nadu mirror what they have begun to observe. Dr Anupama YJ, Consultant Nephrologist at Nanjappa Hospital in Karnataka’s Shivamogga, said kidney disorders are increasingly being seen among those who work long hours outdoors — even among people with no diabetes or hypertension.
“We have noticed an increase in kidney diseases among agriculturists and among people who didn’t have diabetes or hypertension,” she told South First. “It may not be to the same extent as what’s reported from Tamil Nadu, but the pattern is similar.”
Since 2012, Dr Anupama’s team has conducted three community surveys in rural Karnataka, and the results revealed a steady presence of undiagnosed kidney issues. “Most of them were asymptomatic; we found them only because we went door to door and tested their creatinine levels and urine samples,” she explained.
Her observations echoed what the Tamil Nadu study revealed — a large share of affected workers have no visible symptoms and remain unaware until screened.
She believes the Tamil Nadu findings are significant because they draw attention to the role of heat stress and dehydration in damaging kidney function. “There is a strong link, though it hasn’t been conclusively proven,” Dr Anupama said.
She cited research from Tamil Nadu’s salt-pan regions, conducted by scientists at Sri Ramachandra Institute, which showed kidney damage in workers exposed only to extreme heat, without agrochemical contact. “That is one of the clearest pieces of evidence that heat alone can impact kidney health,” she noted.
At the same time, Dr Anupama stressed that rural agricultural work exposes people to multiple stressors acting together: Heat, agrochemicals, inadequate rest and poor hydration.
“It may not be just heat; agrochemicals and poor hydration might act in combination,” she said. “We haven’t conclusively proven it yet, but the pattern across Tamil Nadu and neighbouring regions is too consistent to ignore.”
While the Lancet study highlighted that risks of kidney issues among Tamil Nadu’s agricultural workers are linked to heat stress and dehydration, not everyone views it as an environmental or climate-related crisis.
“This isn’t really an environmental issue,” said Dr R Nagendran, Professor of Environmental Science & Engineering and Enviro-legal consultant. “It’s a physiological response, what happens inside the body when people work for hours under direct sun without adequate hydration,” he explained to South First.
According to him, the rise in kidney-related problems among field workers should be seen more as an occupational hazard than an environmental impact. Long exposure to heat and dehydration, he explained, can aggravate existing health issues but doesn’t create them on its own.
“If someone already has mild kidney problems, the work conditions will make it worse,” he said. “But the real cause is how the person works and what precautions are missing, not the environment itself.”
He also distinguished between environmental damage and individual health responses.
“When we talk about environmental impact, we usually mean how pesticides or fertilisers affect soil, water or air,” he said. “Here, it’s the body reacting to heat and dehydration. It’s not the environment that’s sick, it’s the worker.”
Still, he acknowledged that rising temperatures and erratic weather patterns can make matters worse. “Climate change can accelerate things, but saying this disease is caused by climate change oversimplifies it. It’s about working hours, rest breaks, and hydration, that’s where the real risk lies.”
The environmentalist compared the kidney to a “water treatment unit” that needs a steady flow of water to stay healthy. When workers lose large amounts of fluid through sweat, he explained, the kidneys receive less water for filtration, which increases stress on the organ.
“When you sweat a lot, you don’t just lose water, you lose essential salts too,” he said, adding that it creates an ionic imbalance. “The kidney then works harder, which is why dehydration over time becomes dangerous.”
He pointed out that these problems are not confined to Tamil Nadu alone.
“Whether it’s Punjab or Tamil Nadu, during the summer months, heat is brutal across the tropical belt,” he said. “So, it’s not about one region, it’s about what happens to the body in extreme conditions.”
The expert also noted that inland and coastal regions face different types of heat stress.
“Inland areas have dry heat that quickly drains water from the body, while coastal humidity traps sweat and prevents cooling,” he explained. “Both situations strain the kidneys in different ways.”
In his view, labelling this as an environmental crisis could distract from the more urgent occupational issue.
“We should be careful not to call every heat-related illness a climate-change effect,” he cautioned. “If we blur the line, we’ll miss the real issue — that farm and outdoor workers are exposed to unsafe heat, without proper hydration, rest, or protection.”
(Edited by Muhammed Fazil.)
