How air pollution is aggravating malnutrition in India

JAMBHALI, India – Whenever people ask about the severity of air pollution, Bharti Yadav points toward her decorative door garland. “Every 15 days, it turns black,” she said, highlighting the rampant air pollution. Outside her two-room house in Jambhali village of Western India’s Maharashtra state is a sugarcane nursery, where agricultural residue is frequently burned. “There’s so much smoke that we can’t even look outside the house,” she said about the intensity of the air pollution. This has manifested into severe health ailments, with every family member experiencing breathlessness and coughing. Air pollution became a problem in Jambhali four years ago when several automobile parts manufacturing plants and textile mills emerged near the village. Sugarcane production spiked in the region, leading to the proliferation of nurseries. Every week, hundreds of kilograms of sugarcane tops and leaves are burned as that remains the only solution to eliminate them quickly. Decomposing them takes space and time, often pushing the nursery owners and farmers to burn them. Initially, the over 5,000 residents of Jambhali were concerned about the rising air pollution, but with no feasible solution in sight, almost everyone normalized it. Bharti Yadav’s daughter-in-law, Kiran Yadav, 33, inhaled a lot of air pollutants during her pregnancy, which led to persistent coughing. She kept enduring, which led to the premature birth of her son, Vignesh, who weighed just 1.75 kilograms, leaving him severely malnourished. Kiran’s story is not a unique case. A study found that air pollution exposure during pregnancy led to 5.9 million preterm births globally in 2019. “Despite keeping the door closed, nothing seems to be working. Clean air has now become a luxury.” --— Kiran Yadav, a mother living in Jambhali in India As air pollution levels rise, its hidden impact on children becomes more apparent. While malnutrition has long remained a challenge in several low- and middle-income countries, studies now suggest that exposure to air pollutants during pregnancy and early childhood can exacerbate the problem. Various studies have linked air pollution directly to undernutrition in the past few years. Although burning fossil fuels, industrial emissions, and automobile exhaust are major contributors to air pollution, burning farm residue also impacts the rural population. Between 2003 and 2019, burning agricultural residue in India caused 44,000–98,000 premature deaths yearly due to exposure to particulate matter. India generates roughly 500 million metric tons of crop residue yearly, and 100 million of this is burned, contributing to air pollution. Since women do over 70% of the farmwork, they remain at a higher risk. “I never thought air pollution could be responsible for his malnourishment,” said Vignesh’s father, Anil Yadav, 35. What the Yadav family experienced isn't an anecdotal incident. A growing body of research from several Asian and African countries points to a direct link between air pollution and malnutrition. A cross-sectional study published in the Journal of Tropical Pediatrics in 2021 found that air pollutants, specifically PM2.5 concentrations, could be the reason behind the burden of undernutrition in children under 5 years old in India. PM2.5 refers to minute airborne particulate matter measuring 2.5 micrometers or less that penetrate deeper into the lungs and pose respiratory and cardiovascular health risks. India’s PM2.5 level was 54.4 micrograms per cubic meter in 2023, far exceeding the recommended limit of 5 micrograms per cubic meter. This can have grave consequences as India already has over 1.4 million children with severe malnutrition, and air pollution can further aggravate this. According to the World Health Organization, in 2022, 149 million children under 5 years old were estimated to be stunted (too short for their age) and 45 million wasted (too thin for their height). Undernutrition is responsible for around half the deaths of children under 5 worldwide. A hidden factor in malnutrition During her pregnancy, Kiran experienced tremendous coughing. “Despite taking several medicines, nothing helped,” she shared. Now, her son Vignesh, who is 4 years old, faces a similar problem. “Whenever there is a change in the weather, he starts coughing,” she said. To add to the issues, he began eating less and reached a stage where he would barely eat. The problem of air pollution and undernutrition isn’t restricted to India. A study looked at the impact of air pollution and stunting in three periods: in-utero (during pregnancy), post-utero (after pregnancy to current age), and cumulative (from pregnancy to current age) from 33 sub-Saharan African countries between 2006 and 2019. Published in the Journal of Exposure Science and Environmental Epidemiology in 2023, it found that over 33% of 185,591 children under 5 who were exposed to air pollution were stunted. Exposure to PM2.5 during pregnancy was associated with higher chances of stunting. Its lead author, Prince Amegbor, assistant professor at New York University School of Global Public Health, explained that air pollutants cause oxidative stress, an imbalance in the production, accumulation, and detoxification of reactive oxygen species in cells and tissues. These unstable molecules easily react with other molecules in the body. Since our body relies on oxygen for energy production, this imbalance can reduce oxygen availability, leading to cell and tissue damage and affecting physiological growth. “Research has shown traces of PM2.5 in the placenta, which is meant to filter out pollutants. However, due to the tiny size of particulate matter, it can pass through the system and reach the fetus,” he told Devex. This exposure can impact fetal growth, and when the child is born, they may not grow as expected, leading to stunted growth. For the Yadav family, the connection between air pollution and the deteriorating health of family members has become painfully clear over the years. Like many parents in Jambhali, Kiran is struggling to protect her son from the rising air pollution. “Despite keeping the door closed, nothing seems to be working. Clean air has now become a luxury,” she said. “There is clear evidence that exposure to ambient [particulate matter] is deeply linked to class … mitigating exposure to environmental pollution becomes a matter of equity, as well as a public health concern.” --— Peter Anthamatten, an associate professor at the University of Colorado Denver Household air pollution remains an everyday threat Alongside the other sources of air pollution, children are also affected by exposure to household air pollution. For instance, Premi Chunnilal, 28, from Bargaon village in the northwestern state of Rajasthan, spends most of her time worrying about her son’s weight. Throughout her pregnancy, she worked all day, cooking on a traditional stove that burned firewood daily because the family could not afford cleaner energy sources. “The smoke caused me many problems,” she told Devex. Coughing became a part of her daily life, but she never anticipated that the effects would reach her son. For the past seven months, community health care workers have been warning her of her son Jay’s undernourishment. “I just don’t understand what I can do.” Jay, who is 13 months old, weighs under 6 kilograms. His weight should be above 7 kilograms. He is not alone in this. A study from India looked at the impact of in-utero exposure to air pollution on childhood undernutrition and found higher levels of indoor and ambient air pollution in northern and central India. Even a slight increase in exposure to PM2.5 levels in pregnant mothers, to 1 microgram per cubic meter, led to a 9 and 19 percentage points increase in the prevalence of underweight and anemia. Another paper published in Environmental Health journal in December 2022 found that ambient in-utero PM2.5 exposure led to a lower height-for-age z-score, or HAZ, and increased stunting in 32 African countries between 2005 and 2019. HAZ is a reference measure of a child’s height compared to the average for their age, which helps check their growth and stunting. One of its authors, Peter Anthamatten, associate professor and chair of the Department of Geography and Environmental Sciences at the University of Colorado Denver, told Devex: “Chronic exposure to air pollution can increase the risk of poor health in general, with ample evidence that points to higher risk of cancer, cardiovascular difficulties, and cognitive or neurological impairment later in life.” He advised that for children, extra attention needs to be paid to harmful exposures that affect their developing brains, starting even before birth. For instance, lead exposure puts adults at risk of heart disease, but in children, it can lead to cognitive impairment. No solution in sight According to WHO, a staggering 2.1 billion people, equivalent to one-third of the world’s population, are currently cooking using inefficient stoves or open fires, thereby generating harmful household air pollution. With air pollution posing a severe threat to the health of mothers and children, the lack of viable and accessible solutions is a pressing concern. Many families, unable to afford clean energy sources, resort to burning firewood, plastic, and other harmful materials for cooking. Anthamatten suggested, “A feasible solution is to inform pregnant women and young parents about the dangers of exposure to PM2.5 and the behaviors that could affect exposure as well as a general awareness of PM and where it comes from.” He recommended minimizing exposure to second-hand tobacco smoke and avoiding the combustion of materials in the house, adding that a huge piece of this problem is beyond the control of individuals as most people lack the means to escape exposure to PM2.5 or avoid combustible cooking. “There is clear evidence that exposure to ambient PM is deeply linked to class; the poorest parts of cities frequently contain the highest ambient levels of PM2.5. Consequently, mitigating exposure to environmental pollution becomes a matter of equity, as well as a public health concern,” he said. Amegbor said, “We need to address the socioeconomic imbalance within the society and empower people to switch to alternative, cleaner forms of energy.” Another important thing is raising awareness, as he shared that people often take the association between air pollution and malnutrition out of context. “Whatever is happening isn’t happening in a vacuum — it’s within a social or spatial context. We need to understand how that context predisposes people to air pollutants.” Speaking of the future areas of research needed to address this, he suggested exploring how air pollution interacts with other climate change indicators, like temperature and wind anomalies, and how these combined mechanisms contribute to impaired child growth or malnutrition. With the rising temperature and air pollution, many children like Vignesh remain at risk. The Yadav family has lost count of their visits to several doctors over three years in the hope of overcoming malnutrition. “He escaped death closely,” his grandmother Bharti said. “It took three years for him to beat malnutrition, but rising air pollution and climate change can reverse the progress anytime,” she said fearfully as she brought Vignesh closer to her heart and hugged him tightly.