Recorded at AIHce EXP 2021
A New Diffusive Sampler for Screening a Wider Variety of Environmental Contaminants at Lower Levels
We have developed a new air sampling device featuring six (6) separate samplers incorporated into a single Sampling Station that may be worn on the upper arm of a first responder, war fighter, or other active worker. Each of six (6) Samplers contained in this Sampling Station may be fitted with sampling media that can be analyzed by conventional solvent extraction or by thermal desorption analysis (TDA). The result is a new type of personal sampler than can be used in screening a large number of environmental contaminants at extremely low levels. Diffusive Samplers (Personal Monitoring Badges) have become popular by providing accurate personal sampling results in a cost-effective and convenient fashion. Because this new diffusive Sampling Station contains multiple samplers, it can use multiple sampling media during a single sampling event allowing analysis of a wider variety of contaminants. Further, since the sampler elements are capable of Thermal Desorption Analysis (which analyzes the entire collected sample), the limits of detection with this device can be are far lower than conventional air sampling using solvent extraction (where only a fraction of the collected sample can be analyzed).
Acknowledgements & References: We would like to acknowledge TDA Research, Inc., of Golden, Colorado, and the US Air Force (Wright Patterson Air Force Base) for providing partial funding for this research Co-Authors M.D.R. Peralta, PhD, Assay Technology, Livermore, CA 94551
Presenter/Author: Mr. Charles Manning, PhD, CIH, FAIHA, Assay Technology, Livermore, CA
Thermal Properties of Buckypaper Sorbent used in Newly Developed Volatile Organic Compound (VOC) Sampler
Exposure to Volatile Organic Compounds (VOCs) is one of the most common occupational risks. A new pre-analysis method, photothermal desorption (PTD) have been developed by our group which uses pulses of high-energy light to release analytes from carbonaceous sorbents of diffusive samplers. The method allows faster response and is prone for field work. In the years since PTD was first tested, self-supporting carbon nanotube sorbents (Buckypapers or BPs) have been reliably produced for use as a PTD compatible sampling material. However, further work is needed to fully explore the capabilities of PTD as a method for desorbing VOC samples. The work discussed in this presentation focuses on characterizing the driving thermal phenomena behind PTD. The objectives of the presented work were three-fold: measure the thermal response (i.e. temperature change) of BPs during light irradiation, determine the best method for conducting said measurements, and determine the thermal conductivity (TC) of the material. In fulfilling these objectives, the collected data not only provide a foundation for future studies on the theoretical framework of PTD, but supply end users of the technique with valuable information pertaining to which VOCs are best suited for use with PTD, based on their ability to be successfully desorbed within the generated temperature range.
Acknowledgements & References: This study was supported by The Deep South Center for Occupational Health and Safety (Grant #5T42OH008436-15) from the National Institute of Occupational Safety and Health; NIOSH). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of NIOSH. Additional acknowledgements go to Boyi Guo, from the Department of Biostatistics at the University of Alabama at Birmingham, for contributing his time and statistical knowledge towards modeling the BP thermal response data. Co-Authors J.S. Shedd, Department of Environmental Health Sciences, University of Alabama at Birmingham (UAB), Birmingham AL, USA J. Oh, Department of Environmental Health Sciences, University of Alabama at Birmingham (UAB), Birmingham AL, USA E.L. Floyd, Department of Occupational and Environmental Health, University of Oklahoma, Oklahoma City, OK, USA A.J. Hauser, Department of Physics & Astronomy, University of Alabama, Tuscaloosa, AL, USA W.W. Kuehster, Department of Physics & Astronomy, Universi
Presenter/Author: Dr Claudiu Lungu, University of Alabama at Birmingham (UAB), Birmingham, AL