Fully Exposed: Understanding the Exposome Can Drive the Future of Health and Wellness

Inside Precision Medicine 2/7/24

Although not necessarily the father of exposomics, Christopher Wild certainly gave life to the term exposome in the title of his August 2005 paper published in Cancer Epidemiology, Biomarkers & Prevention. Fresh on the heels of the completion of the Human Genome Project, Wild contended that while the identification of genetic variants or single nucleotide polymorphisms (SNPs) was significant in disease susceptibility and development, most of these variants would only influence human health if perturbed by environmental exposure.

In advocating for broader study of the exposome, which he defined as life-course environmental exposures from the prenatal period and onward, Wild wrote: “Environmental exposures are acknowledged to play an overwhelmingly important role in those common chronic diseases … which constitute the major health burden in economically developed countries. Despite this, many exposure-disease associations remain ill-defined and the complex interplay with genetic susceptibility is only beginning to be addressed.”

However, most researchers, starry-eyed with the wonder of human genome, did not exactly jump to action.

“For the first five years after the term was coined, nothing really happened at all,” noted Fenna Sillé, PhD, an assistant professor in the department of Environmental Health and Engineering at the Johns Hopkins Bloomberg School of Public Health. “Only since 2010 has this started to trickle and get momentum.”

Now, more than a decade later, the field of exposomics is still in its early stages. Pioneering researchers are grappling with methods to marry multi-omic datasets, blood and urine mass spectrometry data, and even postal code and satellite data to gain insights into the highly complex interface between human biology and environmental exposures—and how it affects human health and wellness.

Looking back, and forward

One tack for researchers is to conduct retrospective studies—leveraging data and samples that have already been generated for other research purposes—to search for clues to how environmental effects on biology lead to the development of disease.

While using data and samples from earlier studies can be a good first step, there are shortcomings to this approach. Sample collection and storage for exposome studies can be tricky, according to Dana Dolinoy, PhD, a professor of environmental health science and nutritional science in the University of Michigan School of Public Health. Having access to longitudinal data is a boon, but the containers used for storing samples may be contaminated with metals or endocrine disruptors. “Even though you have these longitudinal cohorts, you’re limited by what was collected and how,” said Dolinoy.

The ideal solution is the development of new, prospective longitudinal studies. These can build cohorts of individuals from the ground up, collect samples to develop baseline data, and follow the cohort for years—even decades—while periodically gathering not only biological samples for analysis, but other data like diet, home environment, socio-economic status, work conditions and exposures, and the participant’s current health status.

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