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Toxicological information

Genetic toxicity: in vivo

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Administrative data

Endpoint:
in vivo mammalian cell study: DNA damage and/or repair
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Justification for type of information:
In-life exposure to fish for up to 14 days at sub-lethal concentrations.
After exposure, blood was taken from the fish and evaluated for DNA damage/repair on the lines of the COMET assay

Data source

Reference
Reference Type:
publication
Title:
Evaluation of multiwalled carbon nanotubes toxicity in two fish species
Author:
Giovani Valentin Cimbaluk et al
Year:
2018
Bibliographic source:
Ecotoxicology and Environmental Safety 150 (2018) 215–223Available online 04 January 2018

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 489 (In vivo Mammalian Alkaline Comet Assay)
Version / remarks:
Fish used
GLP compliance:
not specified
Type of assay:
mammalian comet assay

Test material

Constituent 1
Chemical structure
Reference substance name:
Carbon
EC Number:
231-153-3
EC Name:
Carbon
Cas Number:
7440-44-0
Molecular formula:
C
IUPAC Name:
carbon
Test material form:
solid: particulate/powder
Specific details on test material used for the study:
Multiwalled carbon nanotubes

Test animals

Species:
other: Fish; Danio rerio
Sex:
not specified

Administration / exposure

Route of administration:
other: Immersion
Details on exposure:
The fish were exposes orally, dermally and through gills. There was evidence of carbon in the gut.
Duration of treatment / exposure:
96 hours and 14 days
Doses / concentrations
Dose / conc.:
10 ppm
Remarks:
In water, semi-static exposure
No. of animals per sex per dose:
40 total
Control animals:
yes, concurrent vehicle
Positive control(s):
No

Examinations

Tissues and cell types examined:
Peripheral blood (erythrocytes)
Details of tissue and slide preparation:
Microscope slides were prepared with a blood cell suspension(10μL) in low melting point agarose (120μL) at 37 °C, followed byincubation in lysis solution at 4 °C for 24 h. After lysis incubation, theslides were placed in a NaOH (10 M) and EDTA (200 mM) solution at apH N 13 for 30 min for the DNA denaturation.

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Toxicity:
no effects
Vehicle controls validity:
valid
Negative controls validity:
not applicable
Positive controls validity:
not applicable
Additional information on results:
The comet assay scores were higher than control group at 5 mg/L in the 96 hour test with one group, but there was no statistical significance

Applicant's summary and conclusion

Conclusions:
There was no significant difference in thefrequency of MN or other morphological nuclear abnormalities between the treatment and the control