Benzyl acrylate

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

This study was conducted between 11 April 2017 and 11 May 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study is considered to be reliability 1 as it has been conducted according to OECD Test Guideline 431 : In vitro Skin Corrosion: Human Skin Model Test and in compliance with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

29 July 2016

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Benzyl acrylate

EC Number:

219-673-9

EC Name:

Benzyl acrylate

Cas Number:

2495-35-4

Molecular formula:

C10H10O2

IUPAC Name:

benzyl acrylate

Specific details on test material used for the study:

Identification: BZA
Chemical Name: Benzyl acrylate
CAS No.: 2495-35-4
Batch: 1B182601
Purity: 99.86%
Appearance: Colorless liquid
Expiry Date: 06 March 2018
Storage Conditions: At room temperature, under protection of sunlight
Stability in Solvent: Not indicated by the Sponsor
Purpose of Use: Industrial chemical

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: The EpiDerm™ tissue consisted of normal, human-derived epidermal keratinocytes which have been cultured to form a multilayered, highly differentiated model of the human epidermis

Source strain:

not specified

Details on test system:

Epi-200 Kit Components Needed for the Assay
EpiDerm™ Kit Lot No.: 25811
1 Sealed 24-well plate Contains 24 inserts with EpiDerm™ tissues on agarose
2 24-well plates For MTT viability assay
4 6-well plates For storing inserts, or for topically applying test agents
1 bottle Serum-Free Assay Medium DMEM-based medium
1 bottle DPBS Rinse Solution For rinsing the inserts in MTT assay

MTT-100 Assay Kit Components
1 vial, 2 mL MTT concentrate
1 vial, 8 mL MTT diluent (supplemented DMEM) For diluting MTT concentrate prior to use in the MTT assay
1 bottle, 60 mL Extractant Solution (Isopropanol) For extraction of formazan crystals

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

Test Item Preparation
50 µL (79.4 µL/cm^2 according to guideline) of the test item were dispensed directly onto duplicate EpiDermTM tissue surface

Duration of treatment / exposure:

3 minutes and 60 Minutes

Number of replicates:

2, duplicate tissues were treated with: test substance, positive control or negative control.

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

other: Relative absorbance

Run / experiment:

3 Minute exposure

Value:

100.4

Negative controls validity:

valid

Remarks:

Set to 100%

Positive controls validity:

valid

Remarks:

21.4

Remarks on result:

no indication of irritation

Results 2

Irritation / corrosion parameter:

other: Relative absorbance

Run / experiment:

1 hour incubation

Value:

89.5

Negative controls validity:

valid

Remarks:

Set to 100%

Positive controls validity:

valid

Remarks:

4.3%

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

The optical pre-experiment (colour interference pre-experiment) to investigate the test item’s colour change potential in water did not led to a change in colour.
Optical evaluation of the MTT-reducing capacity of the test item after 1 hour incubation with MTT-reagent did not show blue colour

The test item is considered to be non-corrosive to skin:
• since the viability after 3 minutes exposure is greater than 50% and
• the viability after 1 hour exposure is greater than 15%


The acceptance criteria are met:
• the mean OD of the tissue replicates treated with the negative control is ≥ 0.8 and ≤ 2.8 for every exposure time (range: 1.412 to 1.455)
• the mean viability of the tissue replicates treated with the positive control for 1 hour, is <15% compared to the negative control (4.3%)
• the Coefficient of Variation (CV) in the range 20 – 100% viability between tissue replicates is ≤ 30% (range: 1.0% to 9.8%)

Any other information on results incl. tables

Results after treatment with BZA and the controls

Dose Group	Ex-posure Inter-val	Absor-bance Well 1 (Tissue 1/2)	Absor-bance Well 2 (Tissue 1/2)	Absor-bance Well 3 (Tissue 1/2)	Mean Absor-bance (Tissue 1/2)	Mean Ab-sorbance (OD) of 3 Wells minus Blank	Mean Ab-sorbance (OD) of 2 Tissues	Absor-bance [% of Negative Control]*	CV [%]	Rel. Absor-bance [% of Negative Control]*
Blank		0.037	0.037	0.036	0.037	0.000
Negative Control	3 minutes	1.355	1.484	1.467	1.435	1.399	1.409	99.3	1.0	100.0
		1.437	1.443	1.486	1.455	1.419		100.7
Positive Control		0.362	0.359	0.354	0.358	0.322	0.301	22.8	9.8	21.4
		0.316	0.312	0.322	0.317	0.280		19.9
Test Item		1.410	1.465	1.493	1.456	1.419	1.421	100.8	0.2	100.9
		1.455	1.463	1.462	1.460	1.424		101.1
Blank		0.036	0.036	0.035	0.035	0.000
Negative Control	1 hour	1.467	1.448	1.441	1.452	1.417	1.397	101.4	2.0	100.0
		1.405	1.428	1.403	1.412	1.377		98.6
Positive Control		0.099	0.103	0.102	0.101	0.066	0.060	4.7	13.4	4.3
		0.091	0.089	0.089	0.090	0.054		3.9
Test Item		1.162	1.156	1.145	1.154	1.119	1.133	80.1	1.8	81.1
		1.188	1.187	1.174	1.183	1.147		82.2

*             relative absorbance [rounded values]:

The optical pre-experiment (colour interference pre-experiment) to investigate the test item’s colour change potential in water did not led to a change in colour.

Optical evaluation of the MTT-reducing capacity of the test item after 1 hour incubation with MTT-reagent did not show blue colour.

The test item is considered to be non-corrosive to skin:

•       since the viability after 3 minutes exposure is greater than 50% and

•       the viability after 1 hour exposure is greater than 15%

The acceptance criteria are met:

•       the mean OD of the tissue replicates treated with the negative control is ≥ 0.8 and ≤ 2.8 for every exposure time (range: 1.412 to 1.455)

•       the mean viability of the tissue replicates treated with the positive control for 1 hour, is <15% compared to the negative control (4.3%)

•       the Coefficient of Variation (CV) in the range 20 – 100% viability between tissue replicates is ≤ 30% (range: 1.0% to 9.8%)

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

Criteria used for interpretation of results: EU CLP and UN GHS

Conclusions:

In conclusion, it can be stated that in this study and under the reported experimental conditions, BZA is non corrosive to skin according to EU CLP and UN GHS.

Executive summary:

This in vitro study was performed to assess the corrosive potential of BZA by means of the Human Skin Model Test with EpiDerm™ tissues models.

The test item did not reduce MTT (test for direct MTT reduction), and it did not change colour, when mixed with deionised water (test for colour interference). Consequently, additional tests with freeze-killed or viable tissues to determine correction factors for calculating the true viability in the main experiment were not necessary.

Independent duplicate tissues of EpiDerm™ were exposed to either the test item, the negative control (deionised water) or the positive control (8.0 N KOH) for 3 minutes and 1 hour, respectively.

After exposure to the negative control the absorbance values met the required acceptability criterion of a mean OD570 ≥ 0.8 and ≤ 2.8 for both treatment intervals thereby confirming the acceptable quality of the tissues.

Exposure to the positive control induced a decrease in the relative absorbance as compared to the negative control, both for the 3 minutes exposure period and for the 1 hour exposure period. The 1 hour exposure caused a decrease of the cell viability < 15% of the negative control. The CV in the range 20 – 100% viability between the tissue replicates is ≤ 30%, thus the validity of the test system and the specific batch of the tissue models is confirmed.

After exposure of the tissues to the test item the relative absorbance value did not decrease (100.4%) after 3 minutes exposure. After 1 hour exposure the relative absorbance value was reduced to 89.5%. Both values did not affect the threshold for corrosivity which is defined to be 50% after the 3 minutes exposure and 15% after the 1 hour exposure. Therefore, the test item is not considered to be corrosive.

In conclusion, it can be stated that in this study and under the reported experimental conditions, the test item BZA is non corrosive to skin according to EU CLP and UN GHS.