Registration Dossier

Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2006-2007
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study with acceptable restrictions

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
Unnamed
Year:
2006
Reference Type:
publication
Title:
Unnamed
Year:
2007

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
not specified
Principles of method if other than guideline:
When a polychromatic erythrocyte is developed from a bone marrow erythroblast, the main nucleus is extruded and the cytoplasm becomes anucleated. Micronuclei are easily detected in these cells because they lack the nucleus. Induced chromosome damage is indicated by an increase in the frequency of micronucleated polychromatic erythrocytes in treated animals
GLP compliance:
yes (incl. certificate)
Type of assay:
micronucleus assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
In order to substantiate this evaluation, the Tecarn-Tecnologia Ambiental Ltda accredited before the Ministry of Agriculture and is holder of bio-safety certificates.
BOS samples were collected in CST´s processing plants. The crushed stone is from Brasitalia quarry, located in the municipality of Serra, Brasilia. Crushed stone samples were collected and prepared by the company Kaerne Engenharia Ltda. In compliance with the method defined in NBR 10.007.2007.

Test animals

Species:
mouse
Strain:
not specified
Sex:
male/female
Details on test animals and environmental conditions:
The test has the purpose of assessing possible mutagenic effects of the test substance on” in vivo” eukaryotic cells (polychromatic erythrocytes) by the presence of structures called micronucleus.
These are formed by acentric chromosomal fragments or whole chromosomes that are late, in comparison with the group, in mitotic division and therefore not included in the offspring cell´s nucleus. They can be visualized in the cytoplasm of the cells being analyzed at the end of cellular division.

Administration / exposure

Route of administration:
oral: drinking water
Vehicle:
leachate L/S 4/1
Duration of treatment / exposure:
3 d
Frequency of treatment:
3 in 3 d
Post exposure period:
according to guideline OECD 474
Doses / concentrations
Remarks:
Doses / Concentrations:
3 consecutive concentrations including 2000 mg/kg body weight using a single treatment
Basis:
no data
No. of animals per sex per dose:
each 5
Control animals:
yes
yes, historical
Positive control(s):
The tested substance will be considered potentially mutagenic when it produce a statistically significant increase, around 5%, in the occurrence of micro-nucleated polychromatic erythrocytes in relation to the negative control group. Any positive results obtained in a test using a single dosage should be repeated with three progressive dosages and the positive result is only confirmed if the study presents a response-dosage curve. The analysis of micronucleus occurrence in treated animals also considers historical negative control.

Examinations

Statistics:
Statistical analysis for comparing the experimental group results to the negative control group, as well as for comparing the results of positive and negative controls.

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Toxicity:
no effects
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negative not mutagenic
Slags, steelmaking, converter (BOS) and natural stone form a quarry in Serra, Brasilia, are not mutagenetic or cytotoxic under when tested according to OECD Guideline 474.
Executive summary:

For determination of the genetic toxicity potential of slags, steelmaking, converter (BOS) and natural stone from a quarry in Serra, Brasilia, tests according to OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test) were performed. As the substances are inorganic solids, leachates were prepared with a L/S (liquid/solid) of 1:4 (250 g/L).

Slags, steelmaking, converter (BOS) and natural stone from a quarry in Serra, Brasilia, are not mutagenetic or cytotoxic when tested according to OECD Guideline 474. They do not need to be classified as mutagenic. No signal word and no hazard statement is required.