New methods for evaluation of organic dust aerosols.
Reynolds-SJ; Keefe-T; Tessari-J; Tillery-M
Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, R01-OH-007841, 2007 Oct; :1-49
Nearly one million U.S. men, women, and children working in agricultural production are at risk for occupational lung disease related to organic dust exposures. The primary goals of this project were 1) to evaluate a novel Recombinant Factor C endotoxin assay using organic dusts from livestock environments, 2) to evaluate new methods for measuring inhalable particulates, endotoxins, and glucans/ergosterols that can be used to help establish occupational exposure guidelines for complex organic dusts in swine, poultry, dairy, equine and sheep environments, 3) to evaluate and develop correction factors for direct-reading aerosol instruments that can be readily used by practitioners for interventions. This project involved close collaboration between the High Plains Intermountain Center for Agricultural Health and Safety (HICAHS) at Colorado State University and the University of Iowa's Great Plains Center for Agricultural Health (GPCAH), and complemented and enhanced the related project conducted at that Center. A unique aspect of this study was the laboratory evaluation of sampler performance when influenced by wind. Overall the IOM had the lowest coefficient of variation (best precision) and was least affected by changes in wind speed. The performance of the Button was negatively impacted in poultry environments where larger (feather) particulates clogged the holes in the screen. In addition to wind speed, MMAD and dust type were important factors affecting performance. Conversion factors for dust (mg/rn3) and endotoxin (EU/m3) were estimated based on field studies for ratios of Button/IOM, CFC/IOM, and Cyclone/IOM. This was the first study to develop a method and investigate the use of a new rFC endotoxin assay for agricultural dusts. In general, strong positive correlations exist between the LAL and rFC assays. A GC/EI-MS method for endotoxin analysis was also developed and applied to assessment of 3OHF A distributions. Compared to the parent GC/MS-MS method, it reduces use of toxic chemicals and sample handling, allows sensitive monitoring of the experimental process, and can be used for analysis of very small samples, typical of personal air samples. The direct reading DataRam (PDR) was highly reliable in all field tests and in most of the laboratory tests. Dust type (with different aerosol size distributions) and wind speed are important factors affecting the performance of the PDR. Correction factors were calculated and could be used by researchers and practitioners to calibrate direct reading PDRs, which would be simpler to use in the field and provide results more quickly. This project addressed the need for more research related to organic dusts in agriculture identified by the NIOSH Board of Scientific Counselors, as well as developing practical cost-effective tools for application in engineering and other interventions, also identified as a priority.
Aerosols; Aerosol-particles; Dust-samplers; Dusts; Particulates; Agriculture; Humans; Men; Women; Children; Animals; Lung; Lung-disease; Lung-disorders; Lung-function; Pulmonary-system; Pulmonary-system-disorders; Pulmonary-disorders; Respiratory-system-disorders; Respiration; Farmers; Families; Agricultural-industry; Agricultural-processes; Agricultural-workers; Microorganisms; Fungi
Stephen J. Reynolds Ph.D., CIH, Department of Environmental and Radiological Health Sciences, 154 EHB, Colorado State University, Ft. Collins, CO 80523-1681
Final Grant Report
NTIS Accession No.
National Institute for Occupational Safety and Health
Colorado State University