Chloramide

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

October 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline study, according to GPL..

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Human Skin Model Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Chloramide

EC Number:

234-217-9

EC Name:

Chloramide

Cas Number:

10599-90-3

Molecular formula:

ClH2N

IUPAC Name:

chloranamine

Test material form:

other: solution

Details on test material:

- solution of Monochloramine at 1 %
- Due to the instability of the Monochloramine, the solution is prepared extemporaneously.

Test animals

Species:

other: not applicable

Strain:

other: not applicable

Details on test animals or test system and environmental conditions:

Not applicable

Test system

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

50 µl applied to each tissue.

Duration of treatment / exposure:

- 3 min
or
- 60 min

Number of animals:

Not applicable

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

other: other: Tissue viability (%)

Value:

17

Remarks on result:

other:

Remarks:

Basis: mean. Time point: 3 minutes. (migrated information)

Results 2

Irritation / corrosion parameter:

other: other: Tissue viability (%)

Value:

4.7

Remarks on result:

other:

Remarks:

Basis: mean. Time point: 1 hour. (migrated information)

In vivo

Irritant / corrosive response data:

- Reduction of MTT by test substance:
After the one hour incubation, the MTT solution control (orange/red) remained unchanged. The initial colour of the test substance, Monochloramine/MTT mixture was red and then purple/red with purple colour on the bottom of the well after the one hour incubation indicating the test substance had reduced the MTT. As the test substance had reduced the MTT, freeze killed tissues (which have no metabolic activity but absorb and bind the test substance like viable tissues) were included in the assay together with the live tissues as a control.

- Check for colouring potential of test substance:
The test substance, Monochloramine/water solution and water control were colourless after the 15 minute shaking period. Therefore, the test substance had not shown any potential for colouring water.

Any other information on results incl. tables

The results after the treatment with the test substance are summarised in the following table:

Sample	Tissue viability as % of mean negative control value				Prediction
	3 minute contact		1 hour contact
	Replicate	Mean±SD	Replicate	Mean±SD
Negative Control (purified water)	97.1	100.0 ± 4.038 CV = 0.0	93.9	100.0 ± 8.589 CV = 0.086	Not applicable
	102.9		106.1
Monochloramine	8.3	17.0 ± 12.223 CV Not applicable	5.2	4.7 ± 0.782 CV Not applicable	Corrosive, sub-category 1
	25.6		4.1
Positive control (8.0 N KOH)	11.7	12.3 ± 0.942 CV Not applicable	2.1	1.9 ± 0.269 CV Not applicable	Corrosive, sub-category 1
	13.0		1.7

SD = Standard Deviation                 CV = Coefficient of Variation

The negative control:

The mean optical density of each duplicate negative control value for the three minute and one hour contact were 1.686 and 1.612, respectively. Both values were between the acceptance range of ≥0.8 to ≤2.8.

The positive control:

The mean relative tissue viability of the positive control, 8.0 N potassium hydroxide, for the one hour application was 1.9%. This value was below the maximum acceptable value of 15%.

 Inter-tissue viability difference:

The coefficient of variation (CV) was not applicable for the test substance, Monochloramine, and positive control three minute and one hour applications, as the mean percentage viability was below the 20% - 100 % viability range. All other values did not exceed the CV value of 0.3.

Applicant's summary and conclusion

Interpretation of results:

corrosive

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the experimental conditions of this study, test substance is considered to be corrosive to skin (sub-category 1).

Executive summary:

The objective of this test was to assess the skin corrosivity,in vitro, of the test substance, Monochloramine (solution of 1 % ).

The test substance was applied for three minutes and one hour to the EpiDerm™ three-dimensional human skin model. The model consisted of normal, human-derived epidermal keratinocytes, which had been cultured on 0.6 cm² inserts to form a multilayered, highly differentiated model of the human epidermis with a functional multilayered stratum corneum. The cell viability of the multi layers was determined by mitochondrial dehydrogenase activity assessed by the reduction of MTT (3‑(4,5‑dimethylthiazol‑2‑yl)‑2, 5‑diphenyltetrazolium bromide) to a soluble, coloured, formazan product. The formazan produced was quantified by spectrophotometric measurement. The prediction model uses the percentage viability values (compared to negative control viability) at three minute and one hour exposure times to identify corrosive and non-corrosive substances. 

 

The test substance, Monochloramine, elicited a mean tissue viability of 17.0% for three minute contact and 4.7% for one hour contact and was predicted as corrosive, sub-category 1, in the EpiDerm™ skin corrosivity test.