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Toxicological information

Basic toxicokinetics

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Administrative data

Endpoint:
basic toxicokinetics in vivo
Type of information:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Peer-reviewed data

Data source

Reference
Reference Type:
secondary source
Title:
Experimental study of silica absorption through the digestive tract as a cause of extrapulmonary silicosis
Author:
González Huergo, D. and Rojo Ortega, D.
Year:
1991
Bibliographic source:
Rev Esp Enferm Dig, 80(2):95-98, as cited in: NTP. 2009. Chemical Information Review Document for Silica Flour (Micronized α-Quartz). U.S Department of Health and Human Services

Materials and methods

Objective of study:
absorption
distribution
Principles of method if other than guideline:
Absorption and distribution of silica particles in rats after administration via stomach tube
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): silica particles
- Analytical purity: no data
Radiolabelling:
no

Test animals

Species:
rat
Strain:
Wistar
Sex:
male

Administration / exposure

Route of administration:
other: stomach tube
Vehicle:
not specified
Duration and frequency of treatment / exposure:
no data
Doses / concentrations
Remarks:
Doses / Concentrations:
up to six doses of 50 mg
No. of animals per sex per dose:
no data
Control animals:
not specified

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on absorption:
Silica particles were not observed in the submucosa, muscularis or regional lymph nodes. The liver and the spleen did not show silicotic nodules. The healthy gastrointestinal barrier plays hardly any part in both silica absorption and extrapulmonary silicosis.

Applicant's summary and conclusion

Conclusions:
The healthy gastrointestinal barrier plays hardly any part in both silica absorption and extrapulmonary silicosis.