How Our Environmental Exposures Shape Health in the Human Age
August 21, 2025
Picture this: You wake up to the sound of traffic, check your phone, drink tap water, breathe city air, apply skincare products, and eat breakfast containing traces of pesticides and plastic packaging compounds.
This complex cocktail of environmental exposures—some obvious, most invisible—interacts with your biology in ways science is just beginning to understand. Welcome to the reality of life in the Anthropocene, the current geological era where human activity dominates planetary systems, and welcome to the study of the human exposome.
Just as the Human Genome Project mapped our genetic blueprint, a global scientific movement is now working to decode the totality of our environmental exposures from conception to death 1 .
This effort couldn't be more urgent: as we reshape our planet through climate change, chemical production, and urbanization, we're simultaneously reshaping our own biology.
The term "exposome" was first coined by cancer epidemiologist Christopher Wild in 2005 as a complement to the genome—representing all environmental exposures that affect us throughout our lifetime 2 . Unlike our fixed genetic code, the exposome is dynamic, changing daily based on where we live, what we eat, and how we interact with our environment.
Climate, urban infrastructure, social capital, education level, and economic factors.
Example: Urban heat island effect, neighborhood walkability
Chemicals, diet, lifestyle factors, physical activity, and occupational exposures.
Example: Pesticides in food, air pollution, physical activity
Biological responses to exposures, including inflammation, oxidative stress, and metabolic changes.
Example: Inflammation markers, metabolic changes
| Domain | Components | Example Exposures |
|---|---|---|
| General External | Climate, social capital, education | Urban heat island effect, neighborhood walkability |
| Specific External | Chemicals, diet, lifestyle | Pesticides in food, air pollution, physical activity |
| Internal | Biological response | Inflammation, oxidative stress, metabolic changes |
We live in an age of unprecedented environmental change—the Anthropocene—characterized by what scientists call "planetary boundary transgressions." Climate change, biodiversity loss, and novel chemical entities have created new exposure scenarios that our species has never before encountered 4 .
Studies suggest that environmental factors may contribute to most chronic conditions, including type 2 diabetes, obesity, and heart disease 1 .
"If we really want to influence human health, we have to develop a bold vision and think creatively about how we can work together to study the complex interplay of different environmental exposures."
Rising temperatures, extreme weather events, and changing ecosystems create new exposure scenarios.
Over 350,000 chemicals and chemical mixtures have been registered for production and use worldwide.
More than half the world's population now lives in urban areas with unique exposure profiles.
Until recently, measuring the exposome seemed practically impossible. How could scientists possibly detect and quantify the tens of thousands of chemicals we encounter? Two technological revolutions have changed this outlook:
Wearable sensors—including silicon wristbands that track chemical exposures—along with satellite imagery and remote monitoring have revolutionized our ability to measure external exposures 2 .
| Tool | Function | Example Applications |
|---|---|---|
| High-resolution mass spectrometry | Identifies and quantifies chemicals in biological samples | Measuring thousands of compounds in blood or urine samples |
| Wearable sensors | Monitors personal exposure to environmental factors | Silicon wristbands that track chemical exposures throughout the day |
| Satellite remote sensing | Measures environmental factors at population scales | Assessing air pollution levels, green space, urban heat islands |
| Bioinformatics platforms | Analyzes complex exposure datasets | Identifying patterns in multi-omics data |
| Organ-on-a-chip systems | Models human exposure responses in vitro | Testing toxicity of chemical mixtures without animal models |
| AI and machine learning | Integrates diverse data types and predicts health risks | Identifying exposure interactions associated with disease |
To understand how exposome research actually works in practice, let's examine one landmark effort: the European Exposome Assessment Project, led by epidemiologist Roel Vermeulen of Utrecht University. This ambitious study aims to examine exposome data from 55 million people across Europe 2 .
| Exposure Combination | Health Outcome | Effect Size |
|---|---|---|
| PM2.5 + Noise pollution | Cardiovascular disease | HR: 1.42 [1.31-1.54] |
| Pesticides + Stress | Depression | OR: 2.11 [1.89-2.35] |
| Green space + Social cohesion | Reduced anxiety | OR: 0.68 [0.62-0.75] |
| Life Stage | Critical Exposures | Health Outcomes |
|---|---|---|
| Prenatal | Air pollutants, maternal stress | Preterm birth, neurodevelopmental issues |
| Childhood | Pesticides, lead, social environment | Asthma, cognitive deficits, obesity |
| Adulthood | Occupational chemicals, shift work | Cancer, cardiovascular disease |
"If we want to combat the large burden of chronic diseases, we need to better understand what those drivers are. Without knowing what the sources of those drivers are, we will not be able to devise effective prevention programs."
The ultimate goal of exposome research isn't just to understand our environmental interactions but to use this knowledge to create healthier lives.
Exposome data could enable personalized prevention strategies based on an individual's unique exposure profile 1 .
Exposome mapping can guide targeted interventions at the community level.
Exposome science provides evidence for smarter chemical regulation and urban planning .
Research will increasingly explore environmental exposures with health-promoting potential 8 .
The journey to decode the human exposome will undoubtedly take decades and require unprecedented collaboration across scientific disciplines and geographic boundaries. But the payoff promises to be enormous: not just longer lives, but better, healthier lives in a world where we consciously shape our environments to promote human and planetary flourishing.
The science of the exposome represents a profound recognition that human health cannot be separated from planetary health. In the Anthropocene, we have become the dominant force shaping our environment, which in turn shapes our biology.
As global initiatives like the Exposome Moonshot Forum continue to build momentum 1 , we stand at the threshold of a new era in public health—one that embraces complexity, advances environmental justice, and recognizes that preventing disease requires understanding the invisible universe of exposures that constitute our daily lives.