Ammonium dihydrogen citrate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 March 1987 - 16 April 1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: EPA Pesticide Assessment Guidelines, Subdivision F, hazard Evaluation: Human and Domestic Animals, Series 81: Acute Toxicity and Irritation Studies § 81-6 "Dermal Sensitization Study", EPA 540/9-82-025, November 1982, revised at November 1984

Version / remarks:

November 1984

Deviations:

yes

Remarks:

No re-challenge (not really necessary as unequivocal conclusion could be drawn after first challenge), no reliability check/ historical data.

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

No information available.

Test material

Test material information

Constituent 1

Reference substance name:

Ammonium chloride

EC Number:

235-186-4

EC Name:

Ammonium chloride

Cas Number:

12125-02-9

Molecular formula:

ClH4N

Test material form:

solid: particulate/powder

Details on test material:

Description: Hoe 092297 - Substanz technisch
Appearance: white crystalline

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: Hoe: DHPK (SPFLac)

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Hoechst AG, Kastengrund, SPF - Zucht
- Females (if applicable) nulliparous and non-pregnant: not specified
- Microbiological status of animals, when known: no data
- Age at study initiation: approximately 8 weeks
- Weight at study initiation: 209-293g
- Housing: Group housing of 5 animals in Makrolon cages.
- Diet: Free access to ERKA-Mischfutter Nr. 8300 für Meerschweinchen und Kaninchen
- Water: Free access to water
- Acclimation period: at least 5 days
- Indication of any skin lesions: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 50 ± 20
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12/12
- IN-LIFE DATES: From: 16 March 1987 To: 16 April 1987

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

physiological saline

Remarks:

0.9%

Concentration / amount:

5%

Day(s)/duration:

8

Adequacy of induction:

highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically

Induction 2

Route:

epicutaneous, occlusive

Vehicle:

physiological saline

Remarks:

0.9%

Concentration / amount:

25%

Day(s)/duration:

2

Adequacy of induction:

highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

physiological saline

Remarks:

0.9%

Concentration / amount:

10%

Day(s)/duration:

1

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

20

Details on study design:

RANGE FINDING TESTS:
- The intradermal irritation of the test article was investigated with three additional animals in order to find the minimal irritant test article concentration for the intradermal induction using intradermal injections as in the main study. Concentrations of 0.2, 1 and 5 %(v/v) were used.
- The topical irritation of the test article was investigated in order to find the minimal irritant test article concentration for the dermal induction, and the maximum nonirritating test article concentration for the challenge application using procedures similar to the main study. Concentrations of 1, 10 and 25 % (v/v) were used.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: two: intradermal injections and a closed patch topical application
- Exposure period: 8 days after the injections the topical application was given. Exposure period was 48 hours for the topical application
- Test groups: two pairs of intradermal injections (0.1 mL):
1st pair: Freund's complete adjuvant (FCA) mixed 1:1 with 0.9% physiological saline
2nd pair control group: 0.9% physiological saline
2nd pair test item group: test item (5% (v/v) 0.9% physiological saline)
3rd pair control group: equal amounts of 0.9% physiological saline and FCA/0.9% physiological saline in the ratio 1:1 (v/v)
3rd pair test item group: equal amounts of test item (5% in 0.9% physiological saline) and FCA/0.9% physiological saline mixed in the ratio 1:1 (v/v).
- Closed patch topical application: 0.5 mL of 25% in 0.9% physiological saline
- Site: left flank

B. CHALLENGE EXPOSURE
- No. of exposures: one
- Day(s) of challenge: 14 days after last induction
- Exposure period: 24 hours
- Test groups: one test group consisting of 20 animals
- Control group: one control group consisting of 10 animals
- Site: left flank
- Concentrations: 10%
- Evaluation (hr after challenge): 24 and 48 hours after removal of the patches.

Challenge controls:

A control group of 10 animals was included in the challenge phase.

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

10%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Results 2

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10%

No. with + reactions:

2

Total no. in group:

20

Remarks on result:

other: minimal erythema was observed in 2 animals

Results 3

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

10%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Results 4

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10%

No. with + reactions:

1

Total no. in group:

20

Remarks on result:

other: minimal erythema was observed in 1 animal

Results 5

Reading:

other:

Group:

positive control

Remarks on result:

not measured/tested

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

In accordance with Regulation (EC) No. 1272/2008 and its amendments.

Conclusions:

Based on the results of a skin sensitisation study with guinea pigs (GPMT), performed according to EPA Guideline and under GLP, ammonium chloride is considered not to be a skin sensitizer.

Executive summary:

A guinea pig maximisation test was performed, according to EPA guideline and GLP, to assess the skin sensitising potential of ammonium chloride. 30 female guinea pigs, 20 for the test group and 10 for the control group, were used. The study consisted of an induction phase and a challenge phase. In the induction phase intradermal injections as well as topical application in the shoulder region were given. For the intradermal injections, a concentration of 5 % (v/v) of the substance was used, whereas in the topical application a concentration of 25% (v/v) was used. In the challenge phase the substance was only applied occlusively on the skin in the left flank at a concentration of 10% (v/v). Results of the challenge phase showed minimal erythema in 2 out of 20 animals in the test group 24 hours after application of the substance. 48 hours after application of the substance, 1 out of 20 animals in the test group showed minimal erythema. No oedema was observed in any of the animals. No clinical abnormalities were observed and bodyweight gain was normal during the study. Based on the results of this study, amonium chloride is not classified as a skin sensitizer according to Regulation (EC) No. 1272/2008 and its amendments.