Lithium salt of branched-aliphatic dicarboxylic acid

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014-08-19 to 2014-08-25

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

(July 26, 2013)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)

Version / remarks:

(July 20, 2012)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Test animals

Species:

other: EPISKIN Small Model (TM)

Details on test animals or test system and environmental conditions:

TEST SYSTEM
- Test system: EPISKIN-SM (TM), 0.38 sq.cm, Lot no.: 14-EKIN-031
- Source: SkinEthic Laboratories, Lyon, France
- Acclimation period: preincubated for 26 h at 37°C in 12-well plates

MTT MEDIUM
- MTT concentrate 3 mg/mL in PBS diluted (10x) in Assay medium (final concentration 0.3 mg/mL)
- Source: Sigma Aldrich, Zwijndrecht, The Netherlands

ENVIRONMENTAL CONDITIONS DURING APPLICATION
- Temperature (°C): room temperature

ENVIRONMENTAL CONDITIONS DURING POST-TREATMENT INCUBATION
- Temperature (°C): 35.6-37.5 (continuously monitored)
- Humidity (%): 65-87 (continuously monitored)
- Other: CO2 content: 5.0 +/- 0.5% (monitored once daily on work days)

Test system

Type of coverage:

open

Preparation of test site:

other: no treatment

Vehicle:

unchanged (no vehicle)

Controls:

other: control tissues

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 10.3 to 13. 0 mg

NEGATIVE CONTROL (NC)
- Substance: Phosphate buffered saline (PBS)
- Source: Invitrogen Corporation, Breda, The Netherlands
- Amount(s) applied (volume or weight with unit): 25 µL

POSITIVE CONTROL (PC)
- Substance: 5% (aq) Sodium dodecyl sulphate (SDS) in PBS
- Source: Sigma Aldrich, Zwijndrecht, The Netherlands)
- Amount(s) applied (volume or weight with unit): 25 µL and re-spread after 7 min contact time

Duration of treatment / exposure:

15 min

Observation period:

- Single obeservation after 45 h (Post-treatment incubation time 42 h; Incubation time in MTT-medium 3h)

Number of animals:

3 tissues each per test substance, negative and positive controls.

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): all tissues were washed with PBS
- Time after start of exposure: 15 min
- Other: after rinsing all cell culture inserts were dried, moved to new well and incubated for 42 h at 37°C (post-treatment incubation)

OTHER: CELL VIABILITY MEASUREMENT
conducted after post-treatment incubation
- MTT incubation: cultured and dried inserts transferred to new plates with 2 mL MTT-medium (0.3 mg/mL) and incubated (3h at 37°C)
- Epidermis extraction: after MTT incubation tissues were dried on blotting paper; then epidermis was extracted with 500 µL isopropanol, then stored refrigerated in tubes for 72 h in darkness
- Formazan determination: spectrophotometrically at 570 nm in duplicate with the TECAN Infinite® M200 Pro Plate Reader

SCORING SYSTEM
- Cell viability: calculated for each tissue as percentage of the negative control mean
- Skin irritation potential: according to remaining cell viability

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

other: other: mean tissue viability

Value:

102

Remarks on result:

other:

Remarks:

Basis: mean. Remarks: 102 % of negative control. (migrated information)

Any other information on results incl. tables

Table 1 Mean absorption and tissue viability in the in vitro skin irritation test with Lithium salt of branched-aliphatic dicarboxylic acid

	A (OD570)	B (OD570)	C (OD570)	Mean (OD570)	SD	Mean tissue viability (percentage of control)
Negative control	1.069	1.057	1.047	1.058	+/- 0.011	100
Test substance	1.057	1.098	1.084	1.079	+/- 0.021	102
Positive control	0.371	0.245	0.657	0.425	+/- 0.211	40

 

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The relative mean tissue viability obtained after 15 minutes treatment with Lithium salt of branched-aliphatic dicarboxylic acid compared to the negative control tissues was 102%. Since the mean relative tissue viability for Lithium salt of branched-aliphatic dicarboxylic acid was above 50% after 15 minutes of treatment Lithium salt of branched-aliphatic dicarboxylic acid is considered to be non-irritant.