Electrostatic sampling of airborne microorganisms.
NIOSH 2003 Apr; :1-10
Each year millions of respiratory allergies and infections are caused by airborne microorganisms present in agricultural, industrial and indoor environments. The level of exposure indicated by bioaerosol samplers depends on the instrument used and the sensitivity of the microorganisms. In an effort to collect such microorganisms more gently, at low power and at minimal pressure drop, an electrostatic sampling technique has been developed and evaluated. As a major part of this development, an electrostatic particle-size classifier and a microorganism dispersion device with optional induction charging were developed to study the electric charges on airborne microorganisms. It has experimentally been proven that laboratory-dispersed indoor air bacteria, such as Pseudomonas fluorescens, have a net negative charge. Some of the bacteria were found to carry several thousand negative or positive charges. In contrast, particles of nonbiological origin were found to carry very few positive or negative charges. This finding suggests that the electrostatic sampler may retain airborne microorganisms by its electrostatic collecting field without first charging the microorganisms in the inlet section, thus reducing the complexity and power consumption for sampling in occupational environments.
Air-sampling; Air-sampling-techniques; Airborne-particles; Aerosol-generators; Electrical-charge; Microorganisms; Electrostatic-fields; Sampling-equipment; Sampling-methods; Bioenergetics
Klaus Willeke, Ph.D., Professor, Department of Environmental Health, 107 Kettering Building, University of Cincinnati, P.O. Box 670056, Cincinnati, OH 45267
Final Grant Report
Research Tools and Approaches: Exposure Assessment Methods
National Institute for Occupational Safety and Health
University of Cincinnati