1,10-dichlorodecane

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1,10-dichlorodecane

EC Number:

218-489-6

EC Name:

1,10-dichlorodecane

Cas Number:

2162-98-3

Molecular formula:

C10H20Cl2

IUPAC Name:

1,10-dichlorodecane

Test material form:

liquid

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

other: normal human epidermal keratinocytes (NHEK)

Justification for test system used:

This test uses the EpiDerm™ reconstructed human epidermis model (MatTek) which consists of normal human epidermal keratinocytes (NHEK) and therefore represents in vitro the target organ of the species of interest and closely mimics the biochemical and physiological properties of the upper parts of the human skin, i.e. the epidermis.

Vehicle:

unchanged (no vehicle)

Details on test system:

Prior to treatment, all EpiDerm™ tissues were gently blotted to remove moisture. The test item was applied undiluted. 30 µL (47 µL/cm2) of the test item were dispensed directly atop the EpiDerm tissue. The test item was gently spread to match size of the tissue using a bulb-headed Pasteur pipette.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

1. Negative control 30 µL DPBS
2. Positive control 30 µL 5% SDS solution
3. Test Item 30 µL (undiluted)
The test was performed on a total of 3 tissues per dose group

Duration of treatment / exposure:

60 ± 1 min incubation time

Duration of post-treatment incubation (if applicable):

18 ± 2 h

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Mean

Value:

ca. 95.9

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

Name	Negative Control			Positive Control			Test Item
Tissue	1	2	3	1	2	3	1	2	3
Absolute OD570	1.956	1.874	1.856	0.096	0.102	0.099	1.652	1.930	1.876
	1.969	1.899	1.889	0.097	0.103	0.102	1.670	1.988	1.870
OD570(Blank Corrected)	1.913	1.832	1.814	0.053	0.059	0.057	1.609	1.887	1.834
	1.926	1.856	1.846	0.055	0.061	0.059	1.627	1.945	1.827
Mean OD570of the Duplicates (Blank Corrected)	1.920	1.844	1.830	0.054	0.060	0.058	1.618	1.916	1.830
Total Mean OD570of 3 Replicate Tissues (Blank Corrected)	1.865*			0.057			1.788
SD OD570	0.048			0.003			0.153
Relative Tissue Viability [%]	103.0	98.9	98.1	2.9	3.2	3.1	86.8	102.8	98.2
Mean Relative Tissue Viability [%]	100.0			3.1**			95.9
SD Tissue Viability [%]***	2.6			0.2			8.2
CV [% Viabilities]	2.6			5.4			8.6

The potential of the test item to induce skin irritation was analysed by using the three-dimensional humanepidermismodel EpiDermä(MatTek) comprising a reconstructed epidermis with a functionalstratum corneum.

In the present study 1,10-Dichlorodecane was applied topically to the EpiDermätissue for 60 min followed by a 42 h post-incubation period and immediate determination of cytotoxic effects via MTT reduction assay.

Irritant potential of the test item was predicted from the relative mean tissue viabilities obtained compared to the corresponding negative control tissues concurrently treated with DPBS.

The mixture of 30 µL test item per 1 mL MTT medium showed no reduction of MTT compared to the solvent. The mixture did not turn blue/purple. Therefore, NSMTT equalled 0%.

The mixture of 30 µL of the test item per 300 µl aqua dest. and/or per 300 µL isopropanol showed no colouring detectable by unaided eye-assessment. Therefore, NSC equalled 0%.

The test item showed no irritant effects. The mean relative tissue viability (% negative control) was > 50% (95.9%) after 60 min treatment and 42 h post-incubation.

The controls confirmed the validity of the study. The mean absolute OD₅₇₀ of the three negative control tissues was 0.8 and ≤ 2.8. The mean relative tissue viability (% negative control) of the positive control was  20% (3.1%). Standard deviation of viability of replicate tissues of all dose groups was ≤ 18% (0.2 - 8.2%).

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In this study under the given conditions the test item showed no irritant effects. The relative mean tissue viability after 60 min of exposure and 42 h post-incubation was > 50%. The test item is therefore classified as “non-irritant” in accordance with UN GHS “No Category”.

Executive summary:

1.1.       Summary Results

In the present study the skin irritant potential of 1,10-Dichlorodecane was analysed.The EpiDerm™-Standard Model (EPI-200™), a reconstituted three-dimensional human epidermis model, was used as a replacement for the Draize Skin Irritation Test (OECD TG 404) to distinguish between UN GHS “Category 2” skin irritating test substances and not categorized test substances (“No Category”) which may be considered as non-irritant. Hereby, the test item was applied topically. Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT after a 60 min exposure and 42 h post-incubation periodand compared to those of the concurrent negative controls. The mixture of 30 µL test item per 1 mL MTT medium showed no reduction of MTT compared to the solvent. The mixture did not turn blue/purple. Therefore, NSMTT equalled 0%. The mixture of 30 µL of the test item per 300 µl aqua dest. and/or per 300 µL isopropanol showed no colouring detectable by unaided eye-assessment. Therefore, NSC equalled 0%. The test item showed no irritant effects. The mean relative tissue viability (% negative control) was > 50% (95.9%) after 60 min treatment and 42 h post-incubation.