Dichromium trioxalate

Endpoint summary

Description of key information

The test material showed low level of response and can be considered to be non-irritant to skin with respect to GHS criteria.

Historical animal studies on this class of substance, including neutral oxalate salts, confirm low levels of irritancy.

Precipitation of chromium oxalate in biological media makes direct testing in aqueous systems unreliable.

Assessment of eye irritation based on oxalate salts and chromium salts with neutral pH suggests not classified. Sodium oxalate is not classified as Eye Irritant.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

60 minutes

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Performed to GLP according to recognised methods

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

GLP compliance:

yes (incl. QA statement)

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Vehicle:

unchanged (no vehicle)

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

The test item was applied topically to the corresponding tissues ensuring uniform covering.

Duration of treatment / exposure:

Triplicate tissues were treated with the test item for a period og 60 minutes

Duration of post-treatment incubation (if applicable):

42 hours after washing

Number of replicates:

Three treatment replicates

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Mean

Value:

ca. 59

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

Positive control % viability ca 3.8%
Limit for classification is 50% viability

Interpretation of results:

GHS criteria not met

Conclusions:

Not considered irritating to skin

Executive summary:

The relative mean viability of the test item treated tissues was 59% after a 60 minute exposure period and 42-Hour post-exposure incubation period.

The limit for classification as Skin Irrit 2 is 50% viabiity

The substance is therefore classified as non-irritant, but is borderline.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

4 hours

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Guideline study to GLP performed on low soluble CrIII salt (Chromium Hydroxide)
Although soluble in high concentrations as supplied, dilution in biological media leads to precvipitation of oxalate salts making testing on the eye unreliable by in-vitro method

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Physical state/Appearance: green powderBatch: 001Purity: >99%Expiry Date: not suppliedStorage Conditions: room temperature in the dark

Species:

cattle

Details on test animals or tissues and environmental conditions:

Eyes from adult cattle (typically 12 to 60 months old) were obtained from a local abattoir as a by-product from freshly slaughtered animals. The eyes were excised by an abattoir employee after slaughter, and were placed in Hanks’ Balanced Salt Solution (HBSS) supplemented withantibiotics (penicillin at 100 IU/mL and streptomycin at 100 μg/mL). They were transported to the test facility over ice packs on the same day of slaughter. The corneas were prepared immediately on arrival.

Vehicle:

physiological saline

Controls:

yes, concurrent vehicle

yes, concurrent positive control

Amount / concentration applied:

Applied as 20% solution

Duration of treatment / exposure:

240 minutes at 32 C

Duration of post- treatment incubation (in vitro):

Opacity was observed immediately after rinsing at the end of exposure, and sodium fluorescin was added and incubated at 32 C for 90 minutes prior to observing permeability

Number of animals or in vitro replicates:

Three eyes per treatment type

Irritation parameter:

cornea opacity score

Run / experiment:

Treated eyes

Value:

3.2

Vehicle controls validity:

valid

Positive controls validity:

valid

Irritation parameter:

cornea opacity score

Run / experiment:

Positive control

Value:

103.8

Vehicle controls validity:

valid

Positive controls validity:

valid

The negative control gave opacity of ≤4.1 and permeability ≤0.105. The negative control acceptance criteria were therefore satisfied.

Interpretation of results:

GHS criteria not met

Conclusions:

The test material showed low level of response and can be considered to be non-irritant to eyes with respect to GHS criteria.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Justification for classification or non-classification

The test material showed low level of response and can be considered to be non-irritant to skin and eyes with respect to GHS criteria.

Historical animal studies on this class of substance confirm low levels of irritancy.