Accumulation of mixed mineral dusts in the lungs of rats during chronic inhalation exposure

Journal Article · Sat Apr 01 04:00:00 EST 1989 · Environmental Research; (USA)

DOI:https://doi.org/10.1016/S0013-9351(89)80036-2· OSTI ID:7059164

McMillan, C H; Jones, A D; Vincent, J H; Johnston, A M; Douglas, A N; Cowie, H ^[1]

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1. Institute of Occupational Medicine, Edinburgh (Scotland)

The effects of mixed dust exposure on pulmonary clearance during chronic exposure has been investigated using rats exposed to combinations of toxic and relatively nontoxic dusts: quartz (at respirable dust concentrations of 1 and 10 mg/m{sup 3}) plus titanium dioxide (at 30 and 20 mg/m{sup 3}, respectively), and amosite asbestos (2.5 mg/m{sup 3}) plus titanium dioxide (15 mg/m{sup 3}). The rats were exposed for 5 days per week, and for up to 16 weeks (for quartz) or up to 32 weeks (for asbestos). The lung burdens were compared with previously published results for exposure to single dusts under the same exposure regimens. The main feature of all these comparisons was the absence of significant differences between the lung burdens (at 3, 10, and 38 days postexposure) for single-dust and mixed-dust exposures. There was, however, some reduction in the postexposure clearance (as shown by the lung burdens at 94, 150, and 260 days postexposure) of titanium dioxide which appeared to be due to the presence of quartz in the lung. For the quartz plus titanium dioxide experiments, the lymph nodes were dissected and analyzed separately. These results showed that transfer to lymph nodes accounted for most of the postexposure clearance for titanium dioxide, and almost all of the quartz.

• OSTI ID: 7059164
• Journal Information: Environmental Research; (USA), Journal Name: Environmental Research; (USA) Vol. 48:2; ISSN ENVRA; ISSN 0013-9351
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ASBESTOS
BIOLOGICAL ACCUMULATION
CHALCOGENIDES
CHRONIC EXPOSURE
CLEARANCE
DISPERSIONS
DUSTS
EXCRETION
INHALATION
INTAKE
LUNG CLEARANCE
LYMPH NODES
LYMPHATIC SYSTEM
MINERALS
MIXTURES
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
QUARTZ
SILICON COMPOUNDS
SILICON OXIDES
TITANIUM COMPOUNDS
TITANIUM OXIDES
TOXICITY
TRANSITION ELEMENT COMPOUNDS