Exposing the exposome to elucidate disease

Abstract

Environmental factors, not genes constitute most disease risk. Myriad approaches are attempting to use the latest science and technology to more clearly reveal the complex mix of pollutants that contribute. Google Street View cars traversing the roads of Oakland, CA, once captured a picture that goes beyond the usual map. On weekdays for 1 year starting in May 2015, two cars equipped with air pollution sensors drove city streets repeatedly. They produced a detailed view of air pollutant levels that differed greatly even within a given block (1). It’s the sort of high-resolution detection that promises to greatly improve our understanding of how the environment affects our health. “Being able to understand how our exposures vary at the scales we live gives us a new, powerful tool to better understand health impacts and also be able to mitigate them,” says Steven Hamburg, chief scientist at the Environmental Defense Fund. Google isn't only driving through neighborhoods to update its maps. This car, equipped with an air pollutant sensor, traveled through the streets of Oakland in 2014 and 2015 to get detailed readings of nitric oxide, nitrogen dioxide, and black carbon particles. Image courtesy of Aclima/Google. Approximately 70 to 90% of disease risks are likely attributable to differences in environments (2), as suggested by studies of twins and research tracking groups that move from nations of low to high disease risk (3). In 2005, Christopher Wild, now director of the International Agency for Research on Cancer, coined the term “exposome” to describe the full suite of environmental exposures that a human experiences throughout life, starting at conception (4). These exposures include everything from infections, lifestyle, and stress to radiation, drugs, and pollution, which can all translate into chemical changes within the body that affect health. Researchers have measured environmental exposures for decades. …