1-dodecylpyridinium chloride

Endpoint summary

Description of key information

Patch tests were performed to determine the irritation and allergenic potential of the test chemical.

A 28-year-old male had recurrent itchy dermatitis on the left side of the chest and adjacent area of the arm, where his wife usually rested her head when sleeping. He had noted that the eruption always developed after his wife had used a hair conditioner.

Patch tests with the European standard sense (ICDRG) and the conditioner (tested undiluted) showed a positive reaction only to the conditioner. Later its ingredients and additional quaternary ammonium salts were also tested separately.

Of 23 controls tested with 0.1% aq test chemical, 16 were negative, 6 had a ? +, and 1 a + reaction.

0.1% aqueous test chemical was sensitizing to human skin.

Hence, the test chemical can be considered to be sensitizing to skin.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer reviewed journal.

Qualifier:

according to guideline

Guideline:

other: Patch tests with the European standard series (ICDRG)

Principles of method if other than guideline:

Patch test was conducted to study skin sensitization of chemical.

GLP compliance:

not specified

Type of study:

patch test

Justification for non-LLNA method:

Study was based on the effects observed in human volunteer after exposure of the substance.

Species:

other: Human

Strain:

other: not applicable

Sex:

male

Details on test animals and environmental conditions:

Details on test animal
TEST ANIMALS
- Age at study initiation:28 year old

Route:

epicutaneous, occlusive

Vehicle:

water

Concentration / amount:

0.1 %, .01%

Day(s)/duration:

no data

Adequacy of induction:

not specified

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

water

Concentration / amount:

0.1%

Adequacy of challenge:

not specified

No. of animals per dose:

23

Details on study design:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: Single
- Exposure period: 48 and 72-hrs
- Test groups: Yes
- Control group: 23 controls were tested
- Site: the left side of the chest and adjacent area of the arm
- Frequency of applications: No data
- Duration: No data
- Concentrations: 0.01 and 0.1%


B. CHALLENGE EXPOSURE: no data

Challenge controls:

Yes,
23 controls were tested

Positive control substance(s):

not specified

Key result

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

0.1%

No. with + reactions:

1

Total no. in group:

20

Clinical observations:

Positive reacrtion were observed

Remarks on result:

positive indication of skin sensitisation

Key result

Reading:

2nd reading

Hours after challenge:

72

Group:

other: Control group

Dose level:

0.1 %

Total no. in group:

23

Clinical observations:

Stong positive reaction were observed

Remarks on result:

positive indication of skin sensitisation

Of 23 controls tested with 0.1% aq test chemical ., 16 were negative, 6 had a ? +, and 1 a + reaction.

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

0.1% aqueous test chemical was sensitizing to human skin.
Hence, the test chemical can be considered to be sensitizing to skin.

Executive summary:

Patch tests were performed to determine the irritation and allergenic potential of the test chemical.

A 28-year-old male had recurrent itchy dermatitis on the left side of the chest and adjacent area of the arm, where his wife usually rested her head when sleeping. He had noted that the eruption always developed after his wife had used a hair conditioner.

Patch tests with the European standard sense (ICDRG) and the conditioner (tested undiluted) showed a positive reaction only to the conditioner. Later its ingredients and additional quaternary ammonium salts were also tested separately.

Of 23 controls tested with 0.1% aq test chemical, 16 were negative, 6 had a ? +, and 1 a + reaction.

0.1% aqueous test chemical was sensitizing to human skin.

Hence, the test chemical can be considered to be sensitizing to skin.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

Various studies have been reviewed to ascertain the extent of dermal sensitization caused by the test chemicals in living organisms. These include in vivo experimental studies performed on humans for the test chemical. The results are summarized below:

Patch tests were performed to determine the irritation and allergenic potential of the test chemical.

A 28-year-old male had recurrent itchy dermatitis on the left side of the chest and adjacent area of the arm, where his wife usually rested her head when sleeping. He had noted that the eruption always developed after his wife had used a hair conditioner.

Patch tests with the European standard sense (ICDRG) and the conditioner (tested undiluted) showed a positive reaction only to the conditioner. Later its ingredients and additional quaternary ammonium salts were also tested separately.

Of 23 controls tested with 0.1% aq test chemical, 16 were negative, 6 had a ? +, and 1 a + reaction.

0.1% aqueous test chemical was sensitizing to human skin.

Hence, the test chemical can be considered to be sensitizing to skin.

This is supported by a study performed to evaluate the ingredients responsible for allergy to cosmetics in 147 patients suffering from cosmetic related contact dermatitis.   Patch test procedures were carried out according to internationally accepted methods.12 Van der Bend patch test chambers (van der Bend, Hellevoetsluis, the Netherlands) were used for applying the allergens, and acrylate tape (Fixomull, Beiersdorf, Hamburg, West Germany) for fixation. 0.1% test chemical in water was applied to the skin of 147 human volunteer and observed for effects. The test material was removed after two days and the reactions were read after 20 minutes and again one or two days later. % Positive reactions in 147 volunteers were 1%. Hence, 0.1 % aqueous solution of the test chemical was considered to sensitizing on human skin.

Results from both the human patch tests indicate a very strong possibility that the test chemical certainly has the potential to cause sensitization to skin. Hence, the test chemical can be considered to sensitizing to skin. It can be further classified under the category “Category 1”.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Results from both the human patch tests indicate a very strong possibility that the test chemical certainly has the potential to cause sensitization to skin. Hence, the test chemical can be considered to sensitizing to skin. It can be further classified under the category “Category 1”.