Accession Number:

ADA158323

Title:

Research and Development on Inhalation Toxicologic Evaluation of Red Phosphorus/Butyl Rubber Combustion Products

Descriptive Note:

Rept. for Mar-Jul 83 on Phase 2

Corporate Author:

IIT RESEARCH INST CHICAGO IL

Personal Author(s):

Report Date:

1983-12-01

Pagination or Media Count:

118.0

Abstract:

Exploratory experiments in male and female Sprague-Dawley rats exposed to concentrations of RPBR aerosols ranging from 0.5 to 4 mg1 for 1 to 3 hr periods showed highly significant decreases in pulmonary bactericidal activity to inhaled 35S-K pneumoniae and generally significant decreases in total cell counts in the pulmonary free cells obtained by trachebronchial lavage. Subsequent range finding experiments suggested that exposure concentration is the determining factor in mortality rather than duration and demonstrated that LC50 studies with single exposures, as required in the contract, were not feasible in the range of aerosol concentrations physically attainable with the generators at the air flow rates required in our inhalation exposure system. When, in a follow-up multiple exposure study, rats inhaled RP BR aerosols for 1 hrday for 5 days at concentrations from 1.56 to 3.05 mg1 mortality ranged from 5 to 90 percent and the estimated LC50 value was 2.32 mg 1. When these data were contrasted with observations from two studies with 5 daily 4-hr exposures to 0.35 and 0.99 mg1 of RPBR the importance of exposure concentration over duration in terms of producing more pronounced effects at similar CxT values was evident again. Originator supplied keywords include Adenosine triphosphate Alveolar macrophages Bactericidal activity Cell counts Cellular protein Histopathology Necropsy Obscurants.

Subject Categories:

  • Toxicology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE