'Health isn't shaped by genes alone - it's in the air and all around us'

Time of India

23-05-2025

New Delhi:
India
stands at the cusp of becoming a global leader in
exposomics
research, with the potential to reshape its understanding and prevent the disease, said Dr
Kalpana Balakrishnan
, Dean of Sri Ramachandra Institute of Higher Education and Research.
Balakrishnan
, who was part of a recent forum on exposomics organised by the Johns Hopkins University in Washington DC, told PTI that India's unique blend of traditional and modern health risks makes it "a natural laboratory" for exposome science.
The term "exposome" was coined by Dr Christopher Wild in 2005. It refers to the totality of environmental exposures that individuals experience throughout their lives, from conception to death.
Unlike a genome, which is inherited and fixed, the exposome is dynamic, ever-shifting and deeply intertwined with health outcomes.
Noting that genes and genetic susceptibility alone cannot explain why people develop a chronic disease, Balakrishnan said, "Someone may not have the genetic markers for heart disease or diabetes, but still end up with them because of multiple environmental exposures experienced over a life course. That's the exposome."
While the Human Genome Project advanced genetic science within a decade, diseases affecting the cardiovascular system, endocrine disorders and mental health issues remain poorly understood through genetics alone, she explained, emphasising the need for cutting-edge tools that can capture exposures from chemical, physical, biological and psychosocial hazards and their interactions with lifestyles or living conditions.
When asked about what kind of tools and technologies are needed for exposome mapping, Balakrishnan told PTI that High Resolution Mass Spectrometry (HRMS) that can simultaneously screen thousands of chemical compounds in air, water, soil and food is one of the key technologies.
"You don't just test for what you expect - A, B, and C. You do untargeted analysis to discover D, E, F and beyond. Otherwise, you stay blind to the unknowns," she said.
For biological responses, Next Generation Sequencing (NGS) and a suite of omics platforms, including metabolomics, proteomics, and genomics, are vital.
"These help us understand how internal systems react to exposures," Balakrishnan said, noting that samples from blood, urine and other tissues provide critical biological signatures.
However, exposomics isn't confined to the laboratory. It now includes satellite-generated data for physical exposures like air pollution, urban heat islands, vegetation cover, and land-use changes.
"We can map environmental factors at high spatial resolution for entire populations," she said, adding that this is especially critical for a country like India, where environmental risks vary drastically by region and socioeconomic status.
Highlighting the complexity of exposomic data, Balakrishnan, who is also the director at World Health Organisation (WHO) Collaborating Centre for Occupational Environmental Health, mentioned that mapping it requires deep learning and AI-powered pattern recognition beyond basic statistical methods.
"These computational tools are crucial. We need them to make sense of massive, layered datasets across environmental samples, biological responses, and population demographics," Balakrishnan told PTI.
She further referred to the successful models in the North American and European exposome consortia, where patterns between pollution, green spaces, and genetic variants are predicting risks for diseases like diabetes and cardiovascular conditions.
"Imagine if we could replicate and scale that here in India," she said.
India's opportunity lies in its landscape, which includes traditional public health challenges like poor sanitation and lack of clean water. These challenges exist alongside modern hazards like ultra-processed food, air pollution and psychosocial stress.
"We're seeing exposure overload from both ends," Balakrishnan said. "That's why we need a holistic, integrative framework in the numerous ongoing cohorts in the country, and exposomics can give us that," she added.
Stressing that India cannot rely on siloed scientific approaches, she further stated that it is not just the job of medical scientists.
"We need engineers, economists, social scientists, and urban planners in the room - together with policymakers from the start," she emphasised.
Adding an international perspective, Dr
Rima Habre
, associate professor of environmental health and spatial sciences at the University of Southern California and co-director of the NIH-funded NEXUS Center for Exposome Research Coordination, said India holds immense potential for global collaborations in exposomics.
Speaking to PTI, Habre said, "I connected with Dr Balakrishnan around exposomics at a recent visit to Ahmedabad, India, where we were both invited speakers at an ICMR-NIOH conference.
"I presented our vision in the NEXUS Center, which I co-lead with Dr.
Gary Miller
and Dr.
Chirag Patel
, to link US-based and international researchers and infrastructure for a truly global exposome initiative."
She added that India's diversity of environmental and social stressors, shaped by unique regional policies and cultural practices, offers unparalleled insight into the totality of health-relevant exposures.
"Dr Balakrishnan's work in establishing large, population-based cohorts in India is foundational for exposomics," Habre said, calling for a globally connected but locally governed framework to reduce the environmental burden of disease.
Poornima Prabhakaran, Director of the Centre for Health Analytics Research and Trends (CHART), echoed the sentiments.
India's longitudinal research infrastructure provides a fertile ground to pioneer large-scale exposomics studies tailored to developing country contexts, she told PTI.
"As a global effort to scale exposomics gathers momentum, we must account for a multitude of diverse exposures across geographies and populations spanning biomarkers, environmental risk factors and 'omics'," she said.
This is in light of the recent
Exposome Moonshot Forum
hosted in Washington DC where there is already an effort across EU (EIRENE) and now US (NEXUS) and IREN to initiate this effort globally, Prabhakaran said.