Dichromium trioxalate

Endpoint summary

Description of key information

From extensive work on chromium III salts, there is no evidence of acute toxicity. Some corrosive salts will cause harm at high concentrations, but this is not considered to be a toxic effect.

 

Oxalic acid is classified Acute Tox 4 (oral and dermal) and anecdotal evidence suggest that the toxicity of salts is similar to the acid (ie the acid is not strong enough to be toxic by local contact). Renal problems have been reported in human overdose. Note that in a 70 day repeat dose diatary study, 5000 mg/kg/day oxalic acid was tolerated, but with renal problems. Administration in the diet is likely to have reduced uptake rates.

 

In view of the wealth of data on chromium salts and oxalates, no further animal testing is justified.

It is accepted that there is no dermal absorption of metal salts such as chromium III from dermal contact.  The data for oxalic acid demonstrates potential for toxicity by the dermal route.

The low oral toxicity also suggests low biological impact from contact with chromium III.  It is not considered to be justified to perform further animal tests. Skin penetration experiments on chromium chloride and chromium sulfate (1.2% chromium labelled with 51Cr) with skin chambers glued to the skin of normal volunteers. These chambers were removed at 6, 12, or 24 hours and analysis for radioactive chromium was performed at the site of the chamber as well as in the underlying epidermis and dermis. As no label was found in the lower levels of skin, it was concluded that chromium(III) salts did not permeate through the intact epidermis. Some blood samples and 24-h urine were also examined, and no radioactive chromium was detected.[Mali JWH, Van Kooten WJ, Van Neer CJ (1963) Some aspects of the behaviour of chromium compounds in the skin. Journal of Investigative Dermatology, 41:111–122].

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

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:

Chromium salts – justification for read-acrossAs with all inorganic salts, the significance for toxicity or environmental assessment is the presence of specific ions that will form when in solution or when in biological systems.In the case of Cr III salts, the counter ion will have an effect on solubility and this is itself dependant on the type of media being used and in particular the pH of that media. It is generally accepted that in the case of metal salts, testing with salts that are soluble in the respective test media will ensure maximum exposure of the metal ions. This will include chlorides and nitrates as being more soluble and will indeed have relevance when dissolved in acid media, such as if ingested.Read-across to other chromium III salts is therefore considered valid as long as the exposure in the test system is greater than wold be expected for the substance under review for registration.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Principles of method if other than guideline:

Male Wistar II rats (10 animals per group) were given by gavage 10 or 15 g/kg bw of a chromium oxide preparation in distilled water.

GLP compliance:

no

Remarks:

Performed at academic research institute. Re-testing on animals to GLP is not ethical

Test type:

fixed dose procedure

Specific details on test material used for the study:

Chromium III Oxide

Species:

rat

Strain:

Wistar

Sex:

male

Route of administration:

oral: gavage

Vehicle:

water

Doses:

10 or 15 g/kg bw

No. of animals per sex per dose:

Ten animals per group

Control animals:

not specified

Sex:

male

Dose descriptor:

LD50

Effect level:

> 15 000 mg/kg bw

Based on:

test mat.

Key result

Sex:

male

Dose descriptor:

discriminating dose

Effect level:

> 5 000 mg/kg bw

Based on:

element

Remarks:

Cr 3+

Mortality:

None

Clinical signs:

Ruffled hair

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The LD50 was higher than 15 g/kg bw for the oxideNo adverse effects reportedConsidered suitable for assessment and classification of Cr 3+ salts. It is not justified to perform additional animal testing.

Executive summary:

Male Wistar II rats (10 animals per group) were given by gavage 10 or 15 g/kg bw of a chromium oxide preparation in distilled water. None of the animals died during the study period of 14 days, and the only symptom reported was ruffled hair.

The LD50 was higher than 15 g/kg bw

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

500 mg/kg bw

Quality of whole database:

All data confirms low oral toxicity of chromium III and it it is the oxalate driving the hazardous effects at high concentration.

Acute toxicity: via inhalation route

Endpoint conclusion

Quality of whole database:

In view of the physical form of the substance, inhalation is not seen as a significant route of exposure. Animal testing is not justifed.