Reaction products of 3,3'-thiodi(propionic acid) and alcohols, C11-14-iso-, C13-rich

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From March 23rd to April 12th, 2022

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2022

Report date:

2022

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Version / remarks:

Adopted July 22nd, 2010

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Version / remarks:

Commission Regulation (EU) No.640/2012, published in O.J. L 193, 2012

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Reaction products of 3,3'-thiodi(propionic acid) and alcohols, C11-14-iso-, C13-rich

EC Number:

823-780-1

Cas Number:

1034820-43-3

Molecular formula:

UVCB substance

IUPAC Name:

Reaction products of 3,3'-thiodi(propionic acid) and alcohols, C11-14-iso-, C13-rich

In vivo test system

Test animals

Species:

mouse

Strain:

Balb/c

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Breeding farm VELAZ s.r.o., 161 00, Prague 6 - Ruzyně, Czech Republic, RČH CZ 11760500
- Females: nulliparous and non-pregnant
- Age at study initiation: 8 weeks
- Body weight range at study initiation: In pilot experiment: 17.99-18.75 g; In main test: 17.26 - 19.53 g.
- Housing: Animals in groups in macrolon cages with sterilized softwood shavings.
- Diet: Pelleted standard diet for experimental animals ad libitum (Altromin, manufacturer: Altromin Spezialfutter GmbH & Co. KG, Germany). Microbiological control and content of nutrients is performed according internal standard procedure.
- Water: Drinking tap water ad libitum. Water quality corresponded to Regulation No. 252/2004 Czech Coll. Of Law, Health Ministry.
- Acclimation period: 6 days.
- Indication of any skin lesions: no
- Cage identification: By cage number, study number and group specific colour.
- Animal identification: By felt tip marking (from 1 to 5 per each group and group specific colour).

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 °C ± 3 °C, permanently monitored.
- Humidity (%): 30 – 70 %, permanently monitored.
- Photoperiod: 12 hours light/dark cycle: 6am-6pm/6pm-6am
- Prophylactic arrangement: Cleaning and disinfection of animal room was regularly performed.

Study design: in vivo (LLNA)

Vehicle:

other: DAE 433 – mixture of 40 % dimethylacetamide, 30 % acetone and 30 % ethanol. The vehicle DAE 433 was selected according to Ehling, G. et al., Toxicol., 2005, and is used in the laboratory for approximately 10 years.

Concentration:

- Test item: 100% - 50% - 5% (w/v)
- Positive control: 0.5% (w/v)

No. of animals per dose:

Exposed groups – 15 females (5 animals in three groups)
Positive control group – 5 females
Negative control group – 5 females

Positive control substance(s):

other: Dinitrochlorobenzene (DNCB)

Statistics:

For statistical calculations the software Statgraphic ® Centurion (version XVII, USA) was used. Statistical evaluation of measured parameters was performed by applying the parametric test for testing whether all group samples originate from the same distribution and then the non-parametric two-group Mann-Whitney rank test (probability level 0.05) for two-group comparisons.

Results and discussion

Positive control results:

- The body weights at the positive control group were slightly decreased at the end of study (not statistically significant).
- All animals in the positive control group showed symptoms caused by the application of DNCB: hyperemia of auricle and increased response to stimuli.
- The value of the DPM for the positive control group was statistically significantly increased compared to the negative control.
- The value of SI for positive control group was ≥ 3 (9.76) – the LLNA was efficient.
- At the positive control group the ear weight was statistically significantly increased compared to the negative control group.
- Very slight erythema and well-defined erythema in animals of the positive control group were recorded during the study.

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

1.33

Test group / Remarks:

100% test item group

Results 2

Parameter:

SI

Value:

1.45

Test group / Remarks:

50% test item group

Results 3

Parameter:

SI

Value:

1.42

Test group / Remarks:

5% test item group

Cellular proliferation data / Observations:

CELLULAR PROLIFERATION DATA:
The value of the DPM for all test item groups was statistically significantly increased compared to the negative control.
The values of SI for the 100% (1.33), 50% (1.45) and 5% (1.42) test item groups were below the threshold, and the stimulation index (SI) is < 3.

CLINICAL OBSERVATIONS:
No animals died during the main study. No symptoms of toxicity and no erythema on the application site were observed in all animals from the 100%, 50% and 5% test item groups.

BODY WEIGHTS:
The statistical analysis was performed for body weight at the 1st and 6th day of study. Statistically significant differences were not found. The body weights at the negative control group and at the group of 50% concentration were slightly decreased at the end of study.
Body weight increment was calculated from values of day 6 just before necropsy and day 1 before first application. Body weight increments were slightly decreased at the negative and at the 50% test item group, the body weight increment was negative.
The variability of body weight observed during the study was adequate to species, sex and age of animals used in experiments.

SIGNS OF TOXICITY:
- At the 50% and 100% test item groups, the ear weight was statistically significantly increased compared to the negative control group.
- No erythema of the skin was observed during the clinical observation at 100%, 50% and 5% dose levels.

Any other information on results incl. tables

RESULTS OF PILOT EXPERIMENT:

During the pilot experiment no clinical symptoms of systemic toxicity were observed and there were no mortalities. In treated animals, no erythema, skin reaction and insignificant change of thickness of ears in mouse were observed. Individual body weight of animals was slightly decreased at the end of study. The ear weights in pilot experiment were relatively balanced. No pathological findings were recorded in all 3 mice. The auricular lymph nodes were without pathological changes in all three mice. On the basic of the results of the pilot experiment the following doses 100%, 50%, and 5% were determined for the main study.

 

Applicant's summary and conclusion

Interpretation of results:

other: The test item shall not be classified as "skin sensitizer" based on CLP Regulation EC No. 1272/2008.

Conclusions:

Under the given test conditions, the test item, Propanoic acid, 3,3'-thiobis-, di-C11-14-isoalkyl esters, C13-rich, does not elicit sensitising response in LLNA.

Executive summary:

The test item was tested for the assessment of skin sensitisation potential with the Local Lymph Node Assay (LLNA) with the incorporation of 3H-methyl thymidine radionuclide. The testing was conducted according to the Method B.42 – Skin Sensitisation: Local Lymph Node Assay, Commission Regulation (EU) No.640/2012, published in O.J. L 193, 2012 and OECD Test Guideline No. 429, Skin sensitisation: Local Lymph Node Assay, Adopted 22^nd July 2010. In the pilot experiment, the following concentrations of the test item were used: 100%, 50%, and 5%. For 50% and 5% concentrations the vehicle DAE 433 was used. Based on the results, the following dose levels were selected for main study: 100%, 50%, and 5%. In this study the contact allergenic potential of the test item was evaluated after topical application to female BALB/c mice. Mice were exposed to three concentrations (100%, 50% and 5%) of the test item for 3 consecutive days. For 50% and 5% concentrations the vehicle DAE 433 were used. The positive control item was Dinitrochlorobenzene (DNCB) in vehicle DAE 433. Primary proliferation of lymphocytes in the lymph node draining the site of application was evaluated using radioactive labelling of proliferating cells. The ratio of the proliferation in treated groups to that in vehicular controls, termed the Stimulation Index (SI), was determined. The evaluation of ear weight was performed for elimination of false positive findings with certain skin irritants. There were no mortalities. The animals exposed to 100%, 50% and 5% test item showed no skin reactions and no other negative clinical symptoms of intoxication throughout the experiment. Nevertheless, statistically significantly increased ear weight at the 50% and 100% dose level was recorded compared to the negative control, but without dose–response relationship. The values of SI for the test groups treated by the test item were below the threshold, stimulation index (SI) is < 3 [100% (1.33) 50% (1.45) and 5% (1.42)] but the value of disintegrations per minute (DPM) for all test item groups is statistically significantly increased compared to negative control (without dose–response relationship). The positive control item, Dinitrochlorobenzene (DNCB), as a known contact allergen (0.5% (w/v)) elicited the expected reaction pattern with a significant increase in the Stimulation Index (9.76) and ear weight. Appropriate performance of the assay in the test laboratory was therefore demonstrated. Under the given test conditions, the test item demonstrated a negative sensitising response in the LLNA assay. The SI at all dose levels (100%, 50% and 5%) was ≤3. Negative results in cell proliferation revealed that the test item is not a contact allergen in mice.