Considerations for the design and technical setup of a human whole-body exposure chamber

Abstract

Exposures to air contaminants, such as chemical vapors and particulate matter, pose important health hazards at workplaces. Short-term experimental exposures to chemical vapors and particles in humans are a promising attempt to investigate acute effects of such hazards. However, a significant challenge in this field is the determination of effects of co-exposures to more than one chemical or mixtures of chemical vapors and/or particles. To overcome such a challenge, studies have to be conducted under standardized exposure characterization and real time measurements, if possible. A new exposure laboratory (ExpoLab) was installed at IPA, combining sophisticated engineering designs with new analytical techniques, to fulfill these requirements. Low-dose as well as high-dose exposure scenarios are achieved by means of a calibration-gas-generator. Exposure monitoring can be carried out with a high performance real time mass spectrometer and other suitable analyzers (e.g. gas chromatograph). Numerous automated security facilities guarantee the physical integrity of the volunteers, and the waste atmosphere is removed using either charcoal filtration or catalytic post-combustion. Measurements of sulfur hexafluoride, carbon dioxide, aniline and carbon black are presented to demonstrate the performance of the exposure unit with respect to the temporal and spatial stability of generated atmospheres. The variations of generated contents in the atmospheres at steady state are slightly higher than the measurement precision of the analyzers (the typical standard deviation of generated atmospheres is < 2%). The technical components of ExpoLab and its monitoring systems ensure high quality standards in validity and reliability of generating and measuring exposure atmospheres.

Keywords::

• Human exposure unit
• chemical vapors
• particles
• occupational health

Acknowledgements

The authors would like to thank all participants and are also grateful to Prof. Dr. N. Koch (Fraunhofer ITEM Hannover–Fraunhofer Institute for Toxicology and Experimental Medicine, Germany), Chr. Monz (IGF Dortmund - Research Institute for Hazardous Substances, Germany), R. Duisenberg (Prof. Dr.-Ing. Dirk Bohne Ingenieure GmbH, Germany), Dr. D. Breuer (IFA Sankt Augustin - Institute for Occupational Safety and Health, Germany), and Dr. M. Schmäh (IAS GmbH, Germany) for consulting and technical support.

Declaration of interest

The authors report no conflicts of interest.