4-(2-hydroxyethyl)piperazin-1-ylethanesulphonic acid

Endpoint summary

Description of key information

Skin sensitisation in vivo (OECD TG 406): no skin sensitisation potential (reference 7.4.1 -1).

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

Study period:

Sep 16 - Oct 31, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

July 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Version / remarks:

30 September 1996

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

This study was conducted due to non-REACH regulatory requirements. With the existing data from this study not only being acceptable but of good quality (Klimisch Score 1), this study precludes the need for an additional LLNA study. In addition, a supplementary LLNA study would violate the ECHA objectives with regards to animal welfare.

Species:

guinea pig

Strain:

Dunkin-Hartley

Remarks:

HsdPoc:DH

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Breeder: Harlan Winkelmann GmbH, Borchen
- Age at study initiation: : about 5 weeks
- Weight at study initiation: 337 g (range from 308 to 374 g)
- Housing: two guinea pigs were housed in a Makrolon cage type with a shelter placed on mobile racks
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): of 20 - 22
- Humidity (%): 45 - 75
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: From: day 1 To: day 25

Route:

intradermal

Vehicle:

other: sodium chlorid solution or an FCA preparation (Freund's complete adjuvant)

Concentration / amount:

25 g/L / 0.1 mL

Day(s)/duration:

7

Adequacy of induction:

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

Route:

epicutaneous, occlusive

Vehicle:

other: sodium chlorid solution or an FCA preparation (Freund's complete adjuvant)

Concentration / amount:

400 g/L / 1 mL

Day(s)/duration:

2

Adequacy of induction:

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

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: sodium chlorid solution or an FCA preparation (Freund's complete adjuvant)

Concentration / amount:

400 g/L / 0.5 mL

Day(s)/duration:

1

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

Pretest: 5 females
Group 1: negative control group (5 females)
Group 2: test material group (10 females)

Details on study design:

RANGE FINDING TESTS:
To determine the concentrations suitable for the main study, a pretest with single intradermal or topical administrations of the vehicle and of the test item preparations was performed. Intradermal (i.d.) injections were given to one animal. Four further animals were used to determine the topical concentrations for the main study. Two of the guinea pigs were exposed for 48 hours without pretreatment to determine the concentration for the dermal induction. The other two animals were treated according to the control group including intradermal injections with FCA. One week after topical induction the two animals of the pretest group were exposed for 24 hours to different test material concentrations to find out the challenge concentration. In the pretest the following concentrations were used:

1. Test item with sodium chlorid solution as vehicle:
intradermal: 50, 25, 10, 5, and 1 g/L
2. Test item with sodium chlorid solution as vehicle:
topical: 400, 200, 100, and 10 g/L
topical with FCA: 400, 200, 100, and 10 g/L

For the main study the following concentrations were chosen:
Vehicle: Sodium chlorid solution for intradermal induction, topical induction and for challenge
Intradermal induction: 25 g/L slightly irritant
Topical induction: 400 g/L slightly irritant
Topical challenge: 400 g/L not irritant

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2 (intradermal and epicutaneous)
- Exposure period: 21 days
- Application:
Intradermal:
- Test groups:
cranial: 0.10 mL Freund's complete adjuvant + sodium chloride solution
medial: 0.10 mL test substance (25 g/L sodium chlorid solution)
caudal: 0.10 mL Freund's complete adjuvant with test substance + sodium chloride solution (25 g test material/L preparation)
- Control group:
Intradermal:
cranial: 0.10 mL Freund's complete adjuvant + sodium chloride solution
medial: 0.10 mL Sodium chlorid solution
caudal: 0.10 mL Freund's complete adjuvant + sodium chloride solution

Epicutaneous: filter paper patch of about 8 cm² fully soaked with 1 mL of the test material preparation (test group) or the vehicle (control group)

- Frequency of applications: once each
- Duration: 7 days (intradermal); 2 days (epicutaneous)
- Concentrations: intradermal (25 g/L); epicutaneous (400 g/L)

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: 1
- Exposure period: 1
- Test groups: filter papers of about 4 cm² fully loaded with 0.5 mL of the test substance preparation
- Control group: filter papers of about 4 cm² fully loaded with 0.5 mL of sodium chlorid solution
- Site: flank
- Concentrations: 400 g/L
- Evaluation (hr after challenge): 48 and 72 hours

Positive control substance(s):

yes

Remarks:

2-Hexylcinnamaldehyde

Positive control results:

After challenge with a-Hexylcinnamaldehyde (25 g/L) positive reactions in 30 % of the animals in the first reading and 10% of the animals in the second reading were observed.

Key result

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

400 g/L

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Key result

Reading:

2nd reading

Hours after challenge:

72

Group:

test chemical

Dose level:

400 g/L

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

48

Group:

negative control

Dose level:

0 g/L

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

no indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

72

Group:

negative control

Dose level:

0 g/L

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

48

Group:

positive control

Dose level:

10 g/L

No. with + reactions:

5

Total no. in group:

10

Remarks on result:

positive indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

72

Group:

positive control

Dose level:

10 g/L

No. with + reactions:

3

Total no. in group:

10

Remarks on result:

positive indication of skin sensitisation

Interpretation of results:

GHS criteria not met

Conclusions:

The test substance did not cause any sensitising reactions in this guinea pig maximisation test (GPMT).

Executive summary:

The test material was evaluated for skin sensitizing properties in the guinea pig maximization test (GPMT) according to OECD TG 406. Five female guinea pigs in the negative control group (group 1) treated with the vehicle (NaCl solution) and ten females in the test material group (group 2) were investigated (strain: Dunkin Hartley). Induction included intradermal injection of test material preparation in NaCl solution (25 g/L with and without Freund's complete adjuvant) on day 1, and topical application of test material preparation (25 g/L) for 48 hours starting on experimental day 8. Challenge by topical application of test material preparation in NaCl solution for 24 hours (400 g/L) was performed two weeks after topical induction. Readings were done at 48 and 72 hours.

 

Induction with	Challenge with	Positive/ animals (after start of the challenge)		Positive/ animals overall
		48h	72h
Test item	Test item	0/10	0/10	0/10

 

After challenge no positive reactions in the test material treated skin sites at both readings were seen. Under the given experimental conditions, the test substance showed no positive response. Thus, it can be regarded as non-sensiting to the skin.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

To assess skin sensitizing properties of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid the guinea pig maximization test according to MAGNUSSON and KLIGMAN (1969) has been performed in accordance with OECD TG 406 (reference 7.4.1 -1). 10 female Dunkin Hartley guinea pigs in the test material group were investigated. 5 additional animals served as control. Induction included intradermal injection of test material preparation in NaCl solution (with and without Freund's complete adjuvant) on day 1, and topical application of test material preparation for 48 hours starting on experimental day 8. Challenge by topical application of test material preparation in NaCl solution for 24 hours was performed two weeks after topical induction. Readings were taken at 48 and 72 hours. After challenge no positive reactions in the test material treated skin sites at both readings were seen. Under the given experimental conditions, the test material showed no positive responds.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. Based on available data on skin sensitisation, the test item does not need to be classified and labelled according to Regulation (EC) No 1272/2008 (CLP), as amended for the twelfth time in Regulation (EU) 2019/521.