Sodium dichromate

Genetic toxicity: in vivo

Administrative data

Endpoint:

genetic toxicity in vivo

Remarks:

Type of genotoxicity: other: Various methods

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

Not applicable

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The EU RAR summarises the results of a number of studies of various designs and reilability.

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

other: review

Title:

European Union Risk Assessment Report: chromium trioxide, sodium chromate, sodium dichromate, ammonium dichromate and potassium dichromate

Author:

European Chemicals Bureau

Year:

2005

Bibliographic source:

3rd. Priority List; Volume 53

Materials and methods

Principles of method if other than guideline:

The EU RAR reports the results of a number of studies of various designs.

GLP compliance:

no

Remarks:

Largely literature studies

Type of assay:

other: Various methods

Test material

Test material information

Constituent 1

Reference substance name:

Chromium trioxide

EC Number:

215-607-8

EC Name:

Chromium trioxide

Cas Number:

1333-82-0

Molecular formula:

CrO3

IUPAC Name:

Trioxochromium

Constituent 2

Reference substance name:

Sodium chromate

EC Number:

231-889-5

EC Name:

Sodium chromate

Cas Number:

7775-11-3

Molecular formula:

CrH2O4.2Na

IUPAC Name:

disodium dioxido(dioxo)chromium

Constituent 3

Reference substance name:

Sodium dichromate

EC Number:

234-190-3

EC Name:

Sodium dichromate

Cas Number:

10588-01-9

Molecular formula:

Cr2Na2O7

IUPAC Name:

disodium [(oxidodioxochromio)oxy]chromiumoylolate dihydrate

Constituent 4

Reference substance name:

Potassium dichromate

EC Number:

231-906-6

EC Name:

Potassium dichromate

Cas Number:

7778-50-9

Molecular formula:

Cr2H2O7.2K

IUPAC Name:

potassium dichromate

Test animals

Species:

other: Rats and mice

Strain:

not specified

Sex:

not specified

Administration / exposure

Route of administration:

other: various

Duration of treatment / exposure:

Various treatment schedules were used

Frequency of treatment:

Various treatment schedules were used

Post exposure period:

Various protocols

No. of animals per sex per dose:

Various protocols were used

Examinations

Tissues and cell types examined:

Vartious: including bone marrow, liver, kidney, lung and germ cells

Results and discussion

Any other information on results incl. tables

Parenteral administration of sodium or potassium dichromate or potassium chromate to rats or mice resulted in significant increases in chromosome aberrations and micronucleated cells in the bone marrow and DNA single-strand breaks, interstrand cross-links and DNA-protein cross-links in the liver, kidneys and lung. A mouse spot test involving intraperitoneal injection of potassium chromate gave positive results. Oral studies have been negative but these employed lower dose levels and absorption is known to be poor by the oral route. Overall, it was concluded that water soluble Cr (VI) compounds are in vivo somatic cell mutagens in animal studies. A significant increase in post implantation deaths in a dominant lethal assay was reported in mice following intraperitoneal injection of potassium dichromate.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): positive
The EU RAR concludes, on the basis of the available information, that water-soluble Cr (VI) compounds are genotoxic in vivo in somatic cells and in germ cells.

Executive summary:

The EU RAR summarises the results of a number of studies of genotoxicity in vivo of various designs and different reliability. It is concluded, based on the weight of evidence, that water-soluble Cr (VI) compounds are genotoxic in vivo in somatic cells and in germ cells.