2,2'-(cyclohexylimino)bisethanol

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2011-06-29 to 2011-07-01

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.40 (In Vitro Skin Corrosion: Transcutaneous Electrical Resistance Test (TER))

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 431 (In Vitro Skin Corrosion: Human Skin Model Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2,2'-(cyclohexylimino)bisethanol

EC Number:

224-809-5

EC Name:

2,2'-(cyclohexylimino)bisethanol

Cas Number:

4500-29-2

Molecular formula:

C10H21NO2

IUPAC Name:

2,2'-(cyclohexylimino)bisethanol

Test material form:

other: liquid

Test animals

Species:

other: EpiDerm human epidermis model

Strain:

other: not applicable

Details on test animals or test system and environmental conditions:

organotypic reconstituted three-dimensional model of the human epidermis

Test system

Type of coverage:

other: direct application

Preparation of test site:

not specified

Vehicle:

unchanged (no vehicle)

Controls:

other: two tissues per treatment period for negative control (A. dest.) and positive control (8 N KOH)

Amount / concentration applied:

50 µL

Duration of treatment / exposure:

3 minutes and 60 minutes

Number of animals:

two replicate tissues per treatment period

Details on study design:

2 replicate tissues per treatment period are dosed with the neat test item, the negative control (A. dest.) and the positive control (8 N KOH), repectively. After each treatment period the test item and controls are rinsed off and the tissues are stained via MTT for 3 hours. Isopropanol extracts are measured photometrically at 550 nm.

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

other: other: mean relative tissue viability

Value:

< 50

Remarks on result:

other:

Remarks:

Basis: other: mean tissue viability of the negative control tissues. Time point: 3 min. Remarks: corrosive. (migrated information)

Results 2

Irritation / corrosion parameter:

other: other: mean relative tissue viability

Value:

< 15

Remarks on result:

other:

Remarks:

Basis: other: mean tissue viability of the negative control tissues. Time point: 60 min. Remarks: corrosive. (migrated information)

In vivo

Irritant / corrosive response data:

if mean tissue viability after 3 min is >= 50% and after 60 min is >= 15% of the respective negative control, the test item is classified as non-corrosive

Other effects:

The mixture of 100 µl test item per 1 ml MTT medium showed reduction of MTT compared to the solvent. The mixture turned blue/purple. Treatment of killed tissues with the test item showed that the test item was washed away before the addition of the MTT solution. Therefore, an influence on the assay was not detectable and a quantitative correction of results was not necessary.

Any other information on results incl. tables

3 min.

Name	Negative Control		Test Item		Positive Control
Tissue	1	2	1	2	1	2
absolute OD550 -values	1.823	1.801	1.732	1.702	0.216	0.223
	1.880	1.869	1.801	1.742	0.219	0.216
	1.839	1.800	1.782	1.739	0.219	0.224
OD550(mean of 3 aliquots)	1.847	1.823	1.772	1.728	0.218	0.221
sd	0.029	0.040	0.036	0.022	0.002	0.004
OD550(mean of 2 replicate tissues)	1.835*		1.750		0.220
mean relative tissue viability [%]	100		95		12**
mean inter tissue viability difference [%]***	1.3		2.5		1.3

^*       mean OD₅₅₀ >= 0.8

^**      mean relative tissue viability of the 3 min. positive control <= 30%

^***     inter tissue viability difference <= 30%

60 min.

Name	Negative Control		Test Item		Positive Control
Tissue	1	2	1	2	1	2
absolute OD550 -values	1.915	1.898	0.265	0.243	0.181	0.157
	1.920	1.927	0.271	0.246	0.182	0.160
	1.956	1.824	0.263	0.245	0.182	0.153
OD550(mean of 3 aliquots)	1.930	1.883	0.266	0.245	0.182	0.157
sd	0.022	0.053	0.004	0.002	0.001	0.003
OD550(mean of 2 replicate tissues)	1.907*		0.255		0.169
mean relative tissue viability [%]	100		13		9
mean inter tissue viability difference [%]***	2.5		8.5		14.8

^*       mean OD₅₅₀ >= 0.8

^***     inter tissue viability difference <= 30%

Applicant's summary and conclusion

Interpretation of results:

corrosive

Remarks:

Migrated information Criteria used for interpretation of results: other: OECD 431

Conclusions:

The test item is classified as "corrosive".

Executive summary:

The potential of the test item to induce skin corrosion was analysed by using the three-dimensional human skin model EpiDerm^TM, comprising a reconstructed epidermis with a functional stratum corneum. The undiluted substance was applied topically to the EpiDerm^TM tissue for 3 minutes and 60 minutes respectively, followed by immediate determination of cytotoxic effects via the MTT reduction assay. Corrosivity potential was predicted from the relative mean tissue viabilities obtained after both treatment periods compared to the corresponding negative control tissues concurrently treated with A. dest (distilled water).

The test item showed corrosive effects in that the mean relative tissue viability (% negative control) was > 50% (95%) after3 minute treatment and < 15% (13%) after 60 minute treatment. The controls confirmed the validity of the study. The mean OD₅₅₀ of the two negative control tissues was > 0.8 for each exposure period. The mean relative tissue viability (% negative control) of the positive control was < 30% (12%) after 3 minute treatment. The maximum inter tissue difference of replicate tissues of all dose groups was < 30% (1.3% - 14.8%).

Based on the results of this study, the test item showed corrosive effects. The test item therefore is classified as "corrosive".