Comparison of two biological aerosol sampling methods

Area of Science:

• Environmental Science
• Microbiology
• Air Quality Monitoring

Background:

• Biological aerosol samplers are crucial for monitoring airborne microorganisms.
• The Andersen two-stage microbial impactor is a widely accepted standard.
• Evaluating alternative samplers like the May three-stage glass impinger is essential for improving sampling efficiency and data reliability.

Purpose of the Study:

• To compare the effectiveness and benefits of the May sampler against the Andersen sampler.
• To assess the dependability of May sampler results in relation to Andersen sampler data.
• To determine if the two samplers provide comparable data for biological aerosol monitoring.

Main Methods:

• Side-by-side air sampling was conducted during simulated wastewater spray irrigation events.
• Samples were analyzed for Escherichia coli colony counts and air concentrations.
• Statistical analysis, including linear regression, was used to compare data from both samplers after excluding overloaded Andersen counts.

Main Results:

• A good correlation (r2 = 0.84) was observed between the May and Andersen samplers.
• The May sampler reported, on average, 82% of the microbial counts obtained by the Andersen sampler.
• Despite quantitative differences, the samplers yielded comparable results for biological aerosol concentrations.

Conclusions:

• The May sampler is a viable alternative or complementary tool to the Andersen sampler for biological aerosol monitoring.
• Both samplers can be effectively used together in a sampling program to enhance data collection.
• The study validates the utility of the May sampler in environmental and public health applications involving airborne microbial assessment.