Calcium disulphamate

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:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Calcium disulphamate

EC Number:

237-399-8

EC Name:

Calcium disulphamate

Cas Number:

13770-92-8

Molecular formula:

Ca.2H3NO3S

IUPAC Name:

calcium disulfamate

Specific details on test material used for the study:

Name of test substance: Calcium disulphamate
Test substance No.: 16/0399-1
Batch identification: GM0056-WRS-0220
CAS No.: 13770-92-8
Content: 90.9 g/100 g (for details see Study code: 16L00478)
Identity: Confirmed (for details see Study code: 16L00478)
Homogeneity: The test substance was homogeneous by visual inspection.
Storage stability: The stability under storage conditions over the study period was guaranteed by the sponsor and the sponsor holds this responsibility.
ADDITIONAL TEST SUBSTANCE INFORMATION
pH value: Ca. 7 (undiluted test substance, moistened with deionized water; determined in the lab prior to start of the GLP study)
Physical state / color: Solid / white
Storage conditions: Room temperature

In vitro test system

Test system:

human skin model

Source species:

human

Details on test system:

Three-dimensional human epidermis model
The EpiDermTM model consists of normal, human-derived epidermal keratinocytes which have been cultured to form a multi layered, highly differentiated model of the human epidermis. It consists of organized basal, spinous and granular layers and a multi-layered stratum corneum containing intercellular lamellar lipid layers arranged in patterns analogous to those found in vivo. The EpiDermTM tissues (surface 0.6 cm²) are cultured on specially prepared cell culture inserts (MILLICELLs, 10 mm ∅) and commercially available as kits (EpiDerm™ 200) containing 24 tissues on shipping agarose.

Tissue model: EPI-200
Tissue Lot Number: 23393
Origin: MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean

Value:

95.3

Negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

Individual and mean OD570values, individual and mean viability values, standard deviations andcoefficient of variation

 

Test substance identification		tissue 1	tissue 2	tissue 3	mean SD CV [%]
NC	mean OD570	1.758	2.019	1.930	1.902
	viability [% of NC]	92.4	106.1	101.5	100.0	7.0	7.0
16/0399-1	mean OD570	1.945	1.767	1.727	1.813
	viability [% of NC]	102.3	92.9	90.8	95.3	6.1	6.4
PC	mean OD570	0.052	0.047	0.054	0.051
	viability [% of NC]	2.7	2.5	2.8	2.7	0.2	7.0

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Executive summary:

The objective was to assess the skin irritation and corrosion potential of Calcium disulphamate. By using the currently available methods a single in vitro assay is not sufficient to cover the full range of skin irritating/corrosion potential. Therefore, two in vitro assays were part of this in vitro skin irritation and corrosion test strategy: The Skin Corrosion Test (SCT) and Skin Irritation Test (SIT).

However, in the current case for Calcium disulphamate the results derived with SIT alone were sufficient for a final assessment. Therefore, further testing in SCT was waived. The potential of the test substance to cause dermal irritation was assessed by a single topical application of ca. 25 μL bulk volume (about 8 mg) of the undiluted test substance to a reconstructed three-dimensional human epidermis model (EpiDerm™). The irritation test was performed with three EpiDerm™ tissues which were incubated with the test substance for 1 hour followed by a 42-hour post-incubation period. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/post-incubation by using a colorimetric test. The reduction of mitochondrial dehydrogenase activity measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the test substance treated epidermal tissues is compared to that of negative control tissues. The quotient of the values indicates the relative tissue viability.

The following results were obtained in the EpiDerm™ skin irritation test:

The test substance is not able to directly reduce MTT.

The final mean viability of the tissues treated with the test substance determined after an exposure period of 1 hour with an about 42-hour post-incubation was 95.3%.

Based on the results observed it was concluded that Calcium disulphamate does not show a skin irritation potential in the EpiDerm™ in vitro skin irritation and corrosion test strategy under the test conditions chosen.