Article Text
Abstract
Introduction Characterizing the external exposome requires a combination of different measurement methods for multiple exposures.
Objectives We describe the development of an external exposome assessment system for the EPHOR study, which focuses on cohorts for assessing working life exposures, particularly one case study on shift work and one on respiratory health. The system will be implemented in a weeklong intensive nested study.
Methods A system of measurement using low-cost sensors, passive sampling methods, and a mobile phone app was developed and trialed. The low-cost sensor measures light, UV, noise, particulate matter, temperature and humidity in a high temporal resolution. Additionally, separate activity and heart rate monitors are added to the data stream. Passive sampling is used for a wide spectrum of chemical and biological agents. The phone app is used for asking a set of questions related to health and exposure factors on a daily basis. The low-cost sensor performance was compared to reference monitors in both a controlled laboratory setting (static) and in a free living setting (personal).
Results Initial tests of the low-cost sensor system indicates that correlations with reference monitors are high for controlled laboratory tests but more variable when used in personal monitoring. Additional calibration may be necessary throughout the project, especially for particulate matter, with the possibility of using the raw sensor data (particle numbers of various sizes) calculating mass concentration.
Conclusion A comprehensive protocol to measure the external exposome has been developed. Next steps include the development of external exposome profiles based on the collected data for use in exposure response analysis for various outcomes. It can be challenging to develop a one-size-fits-all external exposome system for exposome studies with different objectives. A flexible platform that can incorporate different sensors or measurement methods is an important feature of external exposome measurement systems.