Research into the human genome has given us access to the potential health benefits of using genetics to diagnose and predict disease. But it has also shown the limits of using genetics to diagnose and predict disease. Scientists are now realizing the important role that environmental factors play in the pathogenesis of many diseases.
Christopher Wild, former director of the International Agency for Research on Cancer, introduced the term “exposome” in an editorial for the journal Cancer Epidemiology, Biomarkers, and Prevention in the year 2005.1 “Most completely, the exposome encompasses life-course environmental pressures (including lifestyle factors) from the prenatal period … In contrast to the genome, the exposome is a very variable and dynamic unit that evolves throughout the life of the individual,” he wrote. To describe the concept as complex would be an understatement – it could contain any number of chemicals or microbes from the environment or from food, as well as chemicals our bodies make in response to the environment or experience.
More than 15 years after the conception of Wild, the concept of exposomes is gaining momentum. A screening study we covered in March is an example of how scientists are trying to remove the real soup of chemicals our bodies swim in. And while the chemicals discovered by the study are noteworthy and perhaps worrying, screening for unknowns – an important avenue for exposome research – distracts analytical science from studies in which a single exposure to one or a few chemicals at a given point in time is measured. In particular, high-resolution mass spectrometry in combination with computational and statistical methods has strengthened the ability of scientists to carry out non-targeted analyzes.
Recognizing meaningful associations from our exposome data is anything but easy. And as with any thriving discipline, standardization is an issue that needs to be addressed. It is important to establish comparable and reproducible methods for exposome research at an early stage in order to ensure the reliability and comparability of the results in different laboratories. Not to mention the consensus of the community to ensure data harmony.
Exposome research certainly faces some challenges, but more studies in this area will be published. Its potential for addressing societal issues and making political decisions makes it a worthy research avenue.