Article

Chemical and physical characteristics of cellulose insulation particulates, and evaluation of potential acute pulmonary toxicity

National Institute of Environmental Health Sciences and the National Toxicology Program, Research Triangle Park, North Carolina 27709, USA.
American Journal of Industrial Medicine (Impact Factor: 1.59). 12/2004; 46(6):554-69. DOI: 10.1002/ajim.20101
Source: PubMed

ABSTRACT During installation of cellulose insulation (CI) in new and older houses, significant quantities of airborne material are generated. This study characterized the chemical and physical properties, and potential acute pulmonary toxicity of CI.
CI from four manufacturers was analyzed for inorganic additives and trace element impurities. Aerosols were generated and size fractionated. The number and size of fibrous and nonfibrous particles in the respirable fractions were determined. Respirable CI particulates were intratracheally instilled in rats (5 mg/kg) to evaluate potential pulmonary toxicity.
CI samples were similar in composition with small differences due primarily to fire retardants. Less than 0.1% of CI was respirable and contained few fibers. Acute exposure to CI caused transient inflammation in the lungs and increased 4-hydroxyproline. Microscopic evaluation revealed a minimal to mild, non-progressing granulomatous pneumonitis.
Low concentrations of respirable particles were found in CI aerosols. Particles consisted primarily of fire retardants with few fibers, and caused mild pulmonary toxicity in rats.

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