Novel Gas Chromatography for Rapid, in situ Workplace Hazardous VOC Analysis

Investigators: Xudong Fan (PI), Katsuo Kurabayashi (Co-I), Richard (Rick) Neitzel (Co-I), Rudy Richardson (Co-I)

Team: Xin Zhang, Lauren Smith

Source of funding: National Institute of Occupational Safety and Health R01 – OH011082

Dates: 2018 – 2021

Description: Workers are exposed every day to various hazardous volatile organic/inorganic compounds (VOCs/VICs) that can affect their safety and long-term health. Gas chromatography (GC) has long been considered to be the most promising and most commonly used method to analyze various VOCs/VICs. However, bench-top GC instruments are bulky and are usually placed in centralized labs, and thus cannot be field-deployable. Meanwhile, existing portable GC and micro-GC (uGC) on the market have limited peak capacity, handle only a small, well-defined set of chemicals, and often fail when encountering complex VOCs/VICs that can be seen in a workplace. Consequently, there is an urgent need for a device capable of rapidly and sensitively analyzing a large number of VOCs/VICs while maintaining portability and being cost-effective.

Methods

We developed a complete fully automated 3-D uGC device built on a chip, which included pre-concentrators, a thermal injector, micro-separation columns, flow controls, and vapor detectors. We used over 100 VOCs/VICs representing various common workplace exposures as model systems to characterize and evaluate the performance of the device. A corresponding VOC/VIC reference library was created for those compounds. We used the developed device, in conjunction with the pre-built VOC/VIC library, to quantitatively analyze VOCs/VICs in an experimental workplace environment and a few real world indoor workplaces. The performance of our developed device was benchmarked against conventional industrial hygiene methods.

Results

Field analysis of occupational VOCs in real time with the 1 × 4-channel 2-D GC device were completed at various locations including a paint shop and a 3D print lab. Measurements were validated against traditional assessment methods using OSHA Method ORG-07 for occupational VOC monitoring. The validation showed that the portable 2-D GC device can analyze the indoor air quantitatively in 5 to 15 min during work processes reasonably accurately as compared to OHSA methods. Rapid on-site detection and analysis of multiple VOCs would allow managers and workers to better characterize VOC exposures and use this information in real-time to reduce the likelihood of over-exposures and consequent adverse health outcomes.

Objectives:

  • To design, micro-fabricate, characterize, and optimize the components for 3-D uGC devices.
  • To assemble the 3-D uGC device and develop the operation/analysis algorithm.
  • To integrate an automated VIC detection module.
  • To characterize and optimize the 3-D uGC device, and create a VOC/VIC reference library.
  • To field-test the 3-D uGC device and benchmark against conventional industrial hygiene methods.

Publications