Copper, diamminebis(nitrato-kO)

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

Deviations:

yes

Remarks:

the deviation is related to the acceptability criteria and has an impact of the conclusion of the study (see below)

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: method B.40bis of the Council regulation No. 440/2008

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Copper, diamminebis(nitrato-kO)

EC Number:

604-942-9

Cas Number:

15414-04-7

Molecular formula:

CuH6N4O6

IUPAC Name:

Copper, diamminebis(nitrato-kO)

In vitro test system

Test system:

human skin model

Remarks:

epiCS

Source species:

human

Cell type:

non-transformed keratinocytes

Vehicle:

unchanged (no vehicle)

Details on test system:

The reconstituted epidermis measured 0.6 cm².
The insert (filter + epidermis) was gently removed from the agarose while avoiding leaving agarose on the polycarbonate filter. The insert was placed in a 6 wells culture plate which had been previously filled with 1 mL of culture medium. The culture dishes were incubated at 37±2°C, 5% CO2 during 20 hours and 20 minutes before treatment. Just before the treatment, the culture medium was replaced by a new culture medium.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

The test item was applied as supplied, at the dose of 25 mg.

Duration of treatment / exposure:

during 3 minutes at room temperature and during 1 hour at 37°C ± 1°C

Number of replicates:

2 living human skin models

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean percent viability of the epidermis skin treated during 3 minutes at room temperature

Value:

ca. 127.31

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean percent viability of the epidermis skin treated during 1 hour at 37°C

Value:

ca. 59.29

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

The item is to be classified as non-corrosive: if the viability after 3 minutes exposure is greater than or equal to 50% and the viability after 1 hour exposure is greater than or equal to 15 %
As the difference of viability between the two treated tissue replicates for the 1 hour treatment, was >30% (87.4%), the acceptability criteria define in OECD 431 are not respected. Moreover one epidermis treated with the test item presented with a viability at 15.60%, which is very closed to the cut off for the classification as corrosive. A second run is necessary to conclude on the corrosive effect of the test item.

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

3 minutes and 1 hour after the test item application, the mean percent viability of the epidermis skins treated with the test item were 127.31 % and 59.29% (102.99% in one epidermis and 15.60% in the other one), versus 8.68% and 0.17%, respectively, with the positive control item (potassium hydroxide 8N).

As the difference of viability between the two treated tissue replicates for the 1 hour treatment, was >30% (87.4%), the acceptability criteria define in OECD 431 are not respected. Moreover one epidermis treated with the test item presented with a viability at 15.60%, which is very closed to the cut off for the classification as corrosive. A second run is necessary to conclude on the corrosive effect of the test item.