The Exposome Approach in Allergies and Lung Diseases: Is It Time to Define a Preconception Exposome?

Abstract

Emerging research suggests environmental exposures before conception may adversely affect allergies and lung diseases in future generations. Most studies are limited as they have focused on single exposures, not considering that these diseases have a multifactorial origin in which environmental and lifestyle factors are likely to interact. Traditional exposure assessment methods fail to capture the interactions among environmental exposures and their impact on fundamental biological processes, as well as individual and temporal factors. A valid estimation of exposure preconception is difficult since the human reproductive cycle spans decades and the access to germ cells is limited. The exposome is defined as the cumulative measure of external exposures on an organism (external exposome), and the associated biological responses (endogenous exposome) throughout the lifespan, from conception and onwards. An exposome approach implies a targeted or agnostic analysis of the concurrent and temporal multiple exposures, and may, together with recent technological advances, improve the assessment of the environmental contributors to health and disease. This review describes the current knowledge on preconception environmental exposures as related to respiratory health outcomes in offspring. We discuss the usefulness and feasibility of using an exposome approach in this research, advocating for the preconception exposure window to become included in the exposome concept.

Addressing Exposome: An Innovative Approach to Environmental Determinants in Pediatric Respiratory Health

“…The exposure assessment should be “holistic” by encompassing several aspects (Variety), and different assessment tools are required for the different exposome domains ( 15 ): conventional survey instruments or advanced sensors for personal monitoring of the specific external exposome , geographic information systems (GIS) for the general external exposome , and biomonitoring and biomarker data for the internal exposome ( 2 , 13 , 30 ). Indeed, how to integrate data across multiple methodological approaches remains a major concern ( 31 ).…”

“…The exposome approach in allergies and lung diseases involves the collection of cumulative measures of external and internal exposures from conception (Volume), and ultimately, from preconception ( 2 ). Levels of environmental contaminants vary during lifetime, and individual changes in lifestyle can increase or decrease exposures ( 30 ).…”

“…allow the integration of a wide range of exposure biomarkers (both exogenous and endogenous) in a single measurement ( 34 ). However, these techniques require the ability of epidemiologists to understand the principles of omics and to identify the most useful biomarkers according to the study hypotheses ( 2 , 30 ). Other challenges related to omics applications include high costs, the lack of standardized procedures, the short follow-up periods (which might not capture the dynamic nature of a disease), and ethical issues ( 2 , 13 , 35 ).…”

“…From a statistical point of view, there is the need for developing methodologies combining omics and exposure data, and for specific expertise to optimize the analyses of complex data involving multiple exposures, mediators, confounders, and outcomes ( 2 ).…”

“…Indeed, understanding the role of the various environmental factors contributing to chronic diseases is challenging, mainly due to limitations in investigation and measurement tools. Since environmental factors generally act in synergy with other exposures and/or biological/behavioral factors, the traditional methods of analysis are unable to capture the whole burden of exposures and their impact on health ( 2 ). In addition, environmental exposures have been usually evaluated at a single time point, whereas emerging evidence suggests that their impact on human health throughout life is dynamic and that crucial time “windows of susceptibility” exist ( 3 ).…”