Course Description:
Recorded at AIHce EXP 2022
Presentations
Assessing Operator Exposures to Biological Agents at a Sewage Treatment Plant — Challenges and Lessons Learned
Using a recently-conducted sewage treatment plant exposure assessment, the challenges involved in conducting assessments for biological agents at any worksite will be discussed. Specific focus points of this session will include: a) options for conducting assessments given the lack of quantitative TLVs or regulatory OELs for most bioaerosols, b) using bioagent risk groups as a component of biological risk assessments, and c) using the Canadian Standards Agency (CSA) control banding approach for biological agents. A surprising source of bacterial endotoxin exposure to plant workers will also be discussed.
Co-Authors
S. Wilde, Stantec Consulting Ltd., Waterloo, ON, Canada
Author
Mr. Craig Maunder, M.Sc., CIH, CSP, Stantec Consulting Ltd. Waterloo, Ontario
Canada
Infection Risk Modeling of SARS-CoV-2 in Air and on Surfaces at a University Campus
The possibility of viral shedding in the vicinity of COVID-19 patients (symptomatic or asymptomatic), is confirmed. Evidence of environmental transmission of the SARS-CoV-2 virus is increasing. Some preventive methods are problematic in certain situations. For example, face coverings, and social distancing are less practical during choir practices and gym workouts. Therefore, knowledge of the contamination level and relative risks associated with different exposure routes is required to prioritize transmission control strategies. To estimate the transmission risks in public buildings, few studies have surveyed simultaneously the presence of SARS-CoV-2 in the air and on surfaces. In our longitudinal environmental surveillance program, we analyzed viral RNA in air and surface samples collected with size-selective wetted wall cyclone bioaerosol high-flow samplers and swab kits. The data was used to build the contamination profile in community and occupational settings on a university campus. Infection risks through inhalation and surface contact under three observed scenarios was then estimated. Our risk modeling results suggest that inhalation is the predominant route of exposure compared to surface contact transmission, which emphasizes the importance of ventilation, social distancing, capacity control, and face covering in controlling airborne transmission.
Co-Authors
J. Wu, U. of Michigan, Dept. of EHS, Ann Arbor MI, USA
L. M. Smith, U. of Michigan, Dept. of EHS, Ann Arbor MI, USA
X. Li, U. of Michigan, Dept. of EHS, Ann Arbor MI, USA
O. Yancey, U. of Michigan, Dept. of EHS, Ann Arbor MI, USA
A. Franzblau, U. of Michigan, Dept. of EHS, Ann Arbor MI, USA
J. T. Dvonch, U. of Michigan, Dept. of EHS, Ann Arbor MI, USA
C. Xi, U. of Michigan, Dept. of EHS, Ann Arbor MI, USA
R. Neitzel, U. of Michigan, Dept. of EHS, Ann Arbor MI, USA
Acknowledgments & References
Thanks to J. Lillemoen, University of Michigan, Department of EHS, Ann Arbor, MI, USA for coordinating the field sampling and to the University of Michigan for funding support.
Author
Xin Zhang, University of Michigan Dept Env Health Sci Ann Arbor, MI
United States of America
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Presentation Date:
05/24/2022
Presenters:
Aurora Le, PhD, MPH, CSP, CPH
Craig Maunder, M.Sc., CIH, CSP
Xin Zhang