Zeolite, cuboidal, crystalline, synthetic, non-fibrous

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jul. 16 -Sep. 16, 2019; experimental phase: Aug. 19-23, 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2019-06-18

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Zeolite, cuboidal, crystalline, synthetic, non-fibrous

EC Number:

930-915-9

Cas Number:

1318-02-1

Molecular formula:

M2/nO • Al2O3 • ySiO2 • wH2O (n is the valency of the cation M, predominantly Na, y can range from 0.64 to 8.8, and w is the number of water molecules (general formula) Na: 1.34 - 24.02%, Al: 2.20 - 39.51%, Si: 15.52 - 68.64% (general composition); additionally, depending on the water quality: Ca, Mg and K might be present below 6%

IUPAC Name:

Zeolite, cuboidal, crystalline, synthetic, non-fibrous

Test material form:

solid: particulate/powder

Remarks:

no surface treatment

Specific details on test material used for the study:

Name: Rive Zeolite (crystalline aluminosilicate)
Batch no.: R - W0170316
Appearance: beige-brown powder
Composition: Zeolite (crystalline aluminosilicate), treated with acid; water
Purity: not applicable, mixture
Homogeneity: homogeneous
Expiry date: Oct. 2021
Storage: Room Temperature (20 ± 5 °C)
CAS No.: 1318-02-1
EC-No.: 215-283-8

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Details on animal used as source of test system:

The test system is a commercially available EpiDerm-Kit, procured by MatTek.
The EpiDermTM tissue consists of human-derived epidermal keratinocytes which have been cultured to form a multi-layered, highly differentiated model of the human epidermis. It con-sists of organized basal, spinous and granular layers, and a multi-layered stratum corneum containing intercellular lamellar lipid layers representing main lipid classes analogous to those found in vivo. The EpiDermTM tissues are cultured on specially prepared cell culture inserts.

Vehicle:

other: DPBS buffer

Details on test system:

One valid experiment was performed.
Three tissues of the human skin model EpiDermTM were treated with the test item for 60 minutes.
The test item was applied directly to each tissue and spread to match the tissue size (0.63 cm²; as indicated by the supplier).
DPBS-buffer was used as negative control and 5% SDS solution was used as positive control.

Control samples:

yes, concurrent vehicle

yes, concurrent positive control

Amount/concentration applied:

24.6-24.8 mg

Duration of treatment / exposure:

60 min

Duration of post-treatment incubation (if applicable):

23 h 25 min

Number of replicates:

3

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

tissue 1 to 3

Value:

ca. 96 - ca. 104.8

Vehicle controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean

Value:

101.3

Vehicle controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

After the treatment with the test item, the mean value of relative tissue viability was increased to 101.3 % (SD: 4.7%). This value is above the threshold for skin irritation potential (50%). Test items that induce values above the threshold of 50% are considered non-irritant to skin.
Tissue viability tissue 1: 96.0%; Tissue viability tissue 2: 103.1%; Tissue viability tissue 3: 104.8%

After treatment with the negative control, the mean absorbance value was within the re-quired acceptability criterion of 0.8 ≤ mean OD ≤ 2.8, OD was 1.7.
The positive control showed clear irritating effects. The mean value of relative tissue viability was reduced to 2.3 % (required: ≤ 20%).
The variation within the tissue replicates of negative control, positive control and test item was acceptable (required: ≤ 18%).

Applicant's summary and conclusion

Conclusions:

The test item Rive Zeolite was considered non-irritant to skin in the Reconstructed human Epidermis (RhE) Test Method. The mean value of relative tissue viability was increased to 101.3 % (mean of three replicates).

Executive summary:

This in vitro study was performed in order to evaluate the potential of Rive Zeolite to evoke skin irritation in a reconstructed human epidermis (RhE) test method.