(2-hydroxypropyl)trimethylammonium 2-ethylhexanoate

Endpoint summary

Description of key information

2017 LLNA  pre-test: The observations in the OECD 429 LLNA pretests are indicative of the substances being corrosive.

Scores of =/> 3 were observed at concentrations 50, 25 and 10%

Ear swelling was greater than 25% in substance 1833500 at 25 and 50%

Body weight loss (>5%) was observed possibly indicative of systemic toxicity.

The main argument for not continuing with the main LLNA studies is the interpretation of the study director with regard to eschar formation at all concentrations tested on day 6.

Based on this observation, and in light of experience with the substance it was decided to apply a precautionary labelling of Corrosive 1C to (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate.

Non guideline study (1975) 75% solution of (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate in ethyleneglycol was was tested for skin irritancy in Albino Rabbits. A single 24 h, occluded application of the test material to the skin of 6 rabbits produced minimal, barely perceptible erythema and no edema. Observation at 72 h was same.

Based on the results of  an eye irritation study in rabbits, Hydroxypropyl, N-2-, N,N,N-trimethylammonium 2-ethylhexanoate 75% in Ethyleneglycol is a primary ocular irritant.

Based on the results of an OECD 437 study (BCOP),  is considered to be a moderate eye irritant.

However, based on observed skin corrosiveness and irritancy, and industrial experience, the substance must be considered as severly irritating to the eye, with the potential to cause severe eye damage.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation / corrosion, other

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2017

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Results of OECD 429 (LLNA) pre-test indicating corrosivity

Justification for type of information:

The OECD 429 (LLNA) test guideline states that

“Dose and vehicle selection should be based on the recommendations given in references (3) and (5). Consecutive doses are normally selected from an appropriate concentration series such as 100%, 50%, 25%, 10%, 5%, 2.5%, 1%, 0.5%, etc. Adequate scientific rationale should accompany the selection of the concentration series used. All existing toxicological information (e.g. acute toxicity and dermal irritation) and structural and physicochemical information on the test substance of interest (and/or structurally related test substances) should be considered where available, in selecting the three consecutive concentrations so that the highest concentration maximises exposure while avoiding systemic toxicity and/or excessive local skinirritation(3)(25).”


.” Excessive local skin irritation is indicated by an erythema score ≥3 and/or an increase in ear thickness of≥25% on any day of measurement(26)(27). The highest dose selected for the main LLNA study will be the next lower dose in the pre-screen concentration series (see paragraph18)that does not induce systemic toxicity and/or excessive local skin irritation.”

Scores of =/> 3 were observed at concentrations 50, 25 and 10%

Ear swelling was greater than 25% in substance 1833500 at 25 and 50%

Body weight loss (>5%) was observed possibly indicative of systemic toxicity.


The main argument for not continuing with the main LLNA studies is the interpretation of the study director with regard to eschar formation at all concentrations tested on day 6.

The definition of corrosivity is not met formally “Corrosivity is defined as irreversible (14 days) damage of the epidermis and dermis following exposure to a substance up to 4 hours on skin”, because observation in the pretests ended on day 6 in the pretests.

However, the observations in the pretests are indicative of the substances being corrosive, which may well have an influence on the proliferation of lymphocytes which in turn would result in a false positive result.

Based on this observation, and in light of experience with the substance it was decided to apply a precautionary labelling of Corrosive 1C to (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate.

Qualifier:

according to guideline

Guideline:

other: OECD 429 Local Lymph Node Assay

Deviations:

not applicable

Principles of method if other than guideline:

LLNA Pretests (x4)

The maximum concentration of test item to be investigated in the LLNA is determined as the dose that can be uniformly applied to the dorsal surface of the ears of the mice and which does at the same time not cause excessive skin irritation or clinical signs of toxicity after three consecutive daily applications.

In the absence of suitable acute toxicity and dermal irritation data or if the information suggests that irritation and/or toxicity is possible, a preliminary screening test will be conducted.

One animal will be treated with the test item at the maximum concentration that is suitable for application to the dorsal surface of the ears and an additional animal will be treated with the next lower concentration of the concentration series mentioned above.
Alternatively, a lower concentration may be investigated first if information is available to suggest that higher concentrations would be irritant or toxic. The animals will be treated, as detailed in the main experiment procedures section, for three consecutive days (days 1, 2 and 3). Clinical signs of toxicity and/or irritation at the treatment sites will be recorded on days 1 to 6 and a score will be used to grade a possible erythema of the ear skin. Furthermore, prior to the first application of the test item (day 1), on day 3 and before sacrifice (day 6) the ear thickness will be determined using a micrometer. Additionally, for both animals, the ears will be punched after sacrifice (day 6) at the apical area using a biopsy punch (Ø 8 mm corresponding to 0.5 cm2 ) and will be immediately pooled per animal and weighed using an analytical balance.

GLP compliance:

yes

Species:

mouse

Strain:

CBA

Type of coverage:

open

Preparation of test site:

other: Mice were treated by (epidermal) topical application to the dorsal surface of each ear

Vehicle:

not specified

Controls:

not required

Amount / concentration applied:

0.25% - 50%

Duration of treatment / exposure:

Animals were treated for three consecutive days (days 1, 2 and 3).

Observation period:

Animals sacrificed 3 days after final treatment (test duration 6 days)

Number of animals:

2 animals per pretest. 4 pretests (8 animals total)

Irritation parameter:

other: eschar formation

Basis:

animal #1

Time point:

other: Day 6

Reversibility:

not reversible

Remarks on result:

other: Eshar formation and ear swelling indicating corrosion at 50% concentration of test substance

Irritation parameter:

other: eschar formation

Basis:

animal #2

Time point:

other: Day 6

Reversibility:

not reversible

Remarks on result:

other: Eshar formation and ear swelling indicating corrosion at 25% concentration of test substance

Irritation parameter:

other: eschar formation

Basis:

animal #3

Time point:

other: Day 6

Reversibility:

not reversible

Remarks on result:

other: Eshar formation and ear swelling indicating corrosion at 10% concentration of test substance

Irritation parameter:

other: eshar formation

Basis:

animal #4

Time point:

other: Day 6

Reversibility:

not reversible

Remarks on result:

other: Eshar formation and ear swelling indicating corrosion at 5% concentration of test substance

Irritation parameter:

other: eschar formation

Basis:

animal #5

Time point:

other: Day 6

Reversibility:

not reversible

Remarks on result:

other: Eshar formation and ear swelling indicating corrosion at 2.5% concentration of test substance

Irritation parameter:

other: eschar formation

Basis:

animal #6

Time point:

other: Day 6

Reversibility:

not reversible

Remarks on result:

other: Eshar formation and ear swelling indicating corrosion at 1% concentration of test substance

Irritation parameter:

other: ear lesions

Basis:

animal: 7

Time point:

other: Day 6

Reversibility:

not reversible

Remarks on result:

other: Eshar formation and ear swelling indicating corrosion at 0.5% concentration of test substance

Irritation parameter:

other: lesions

Basis:

animal: 8

Time point:

other: Day 6

Reversibility:

not reversible

Remarks on result:

other: Eshar formation and ear swelling indicating corrosion at 0.25% concentration of test substance

Irritant / corrosive response data:

The LLNA study was terminated after the fourth pre-test, since eschar formation was observed at all tested concentrations (see details in attached results). This is an indication for corrosive properties of the test item.
After 3 consecutive days of treatment animals showed visible ear swelling, evidence of hardened and scaly skin and lesions that progressed to eschar formation at sacrifice on day 6.

Interpretation of results:

Category 1C (corrosive) based on GHS criteria

Conclusions:

The observations in the OECD 429 LLNA pretests are indicative of the substances being corrosive.

Executive summary:

The OECD 429 (LLNA) test guideline states that:

“Dose and vehicle selection should be based on the recommendations given in references (3) and (5). Consecutive doses are normally selected from an appropriate concentration series such as 100%, 50%, 25%, 10%, 5%, 2.5%, 1%, 0.5%, etc. Adequate scientific rationale should accompany the selection of the concentration series used. All existing toxicological information (e.g. acute toxicity and dermal irritation) and structural and physicochemical information on the test substance of interest (and/or structurally related test substances) should be considered where available, in selecting the three consecutive concentrations so that the highest concentration maximises exposure while avoiding systemic toxicity and/or excessive local skinirritation(3)(25).”

.” Excessive local skin irritation is indicated by an erythema score ≥3 and/or an increase in ear thickness of≥25% on any day of measurement(26)(27). The highest dose selected for the main LLNA study will be the next lower dose in the pre-screen concentration series (see paragraph18)that does not induce systemic toxicity and/or excessive local skin irritation.”

Scores of =/> 3 were observed at concentrations 50, 25 and 10%

Ear swelling was greater than 25% in substance 1833500 at 25 and 50%

Body weight loss (>5%) was observed possibly indicative of systemic toxicity.

The main argument for not continuing with the main LLNA studies is the interpretation of the study director with regard to eschar formation at all concentrations tested on day 6.

The definition of corrosivity is not met formally “Corrosivity is defined as irreversible (14 days) damage of the epidermis and dermis following exposure to a substance up to 4 hours on skin”, because observation in the pretests ended on day 6 in the pretests.

However, the observations in the pretests are indicative of the substances being corrosive, which may well have an influence on the proliferation of lymphocytes which in turn would result in a false positive result.

Based on this observation, and in light of experience with the substance it was decided to apply a precautionary labelling of Corrosive 1C to (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate.

Reference 2

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

equivalent or similar to guideline

Guideline:

other:

Version / remarks:

Section 1500.41. - Hazardous Substances and Articles , Administration and Enforcement Regulations, Federal Register, Vol . 38, No. 187, P. 27019, 27 September 1973.

Principles of method if other than guideline:

Sample was used as supplied. A group of six albino rabbits were clipped over a wide area. One side of the animals' backs was abraded at one side with
a lancet sufficiently deep t o penetrate the stratum corneum but not enter the derma to produce bleeding.
The skin of the other side was allowed to remain intact.
A 0.5 g portion o f material was applied to an abraded and an intact skin siteon the same rabbit. Gauze patches were then placed over the treated areas
and an impervious material was wrapped snugly around the trunks of the animals t o hold the patches in place. The wrapping was removed at the end of
the four hour period and the treated areas were examined. Readings were also made after twenty-four and seventy-two hours.
The Draize method o f scoring was employed.

GLP compliance:

not specified

Control samples:

no

Species:

rabbit

Strain:

not specified

Type of coverage:

occlusive

Preparation of test site:

abraded

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 g of 75% solution of (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate in ethyleneglycol.

Duration of treatment / exposure:

24 h

Observation period:

24h/72h

Number of animals:

6

Details on study design:

Sample was used as supplied. A group of six albino rabbits were clipped over a wide area. One side of the animals' backs was abraded at one side with
a lancet sufficiently deep t o penetrate the stratum corneum but not enter the derma to produce bleeding.
The skin of the other side was allowed to remain intact.
A 0.5 g portion o f material was applied to an abraded and an intact skin siteon the same rabbit. Gauze patches were then placed over the treated areas
and an impervious material was wrapped snugly around the trunks of the animals t o hold the patches in place. The wrapping was removed at the end of
the four hour period and the treated areas were examined. Readings were also made after twenty-four and seventy-two hours.
The Draize method o f scoring was employed.

Irritation parameter:

erythema score

Basis:

mean

Time point:

24 h

Score:

1

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Intact Skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

72 h

Score:

1

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Intact skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

24 h

Score:

0.83

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded Skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

72 h

Score:

1

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded Skin

Irritation parameter:

edema score

Basis:

mean

Time point:

24 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Intact skin

Irritation parameter:

edema score

Basis:

mean

Time point:

72 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Imtact skin

Irritation parameter:

edema score

Basis:

mean

Time point:

24 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded skin

Irritation parameter:

edema score

Basis:

mean

Time point:

72 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded skin

Interpretation of results:

study cannot be used for classification

Conclusions:

75% solution of (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate in ethyleneglycol was was tested for skin irritancy in Albino Rabbits.
A single 24 h, occluded application of the test material to the skin of 6 rabbits produced minimal, barely perceptible erythema and no edema. Observation at 72 h was same.

Executive summary:

75% solution of (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate in ethyleneglycol was was tested for skin irritancy in Albino Rabbits. A single 24 h, occluded application of the test material to the skin of 6 rabbits produced minimal, barely perceptible erythema and no edema. Observation at 72 h was same.

Reference 3

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

equivalent or similar to guideline

Guideline:

other:

Version / remarks:

Section 173.240 (a) (1) Ti t l e 49 C F R

Principles of method if other than guideline:

Sample was used as supplied. A group of six albino rabbits were clipped over a wide area. One side of the animals' backs was abraded at one side with
a lancet sufficiently deep t o penetrate the stratum corneum but not enter the derma to produce bleeding.
The skin of the other side was allowed to remain intact.
A 0.5 g portion o f material was applied to an abraded and an intact skin siteon the same rabbit. Gauze patches were then placed over the treated areas
and an impervious material was wrapped snugly around the trunks of the animals t o hold the patches in place. The wrapping was removed at the end of
the four hour period and the treated areas were examined. Readings were also made after twenty-four and seventy-two hours.
The Draize method o f scoring was employed.

GLP compliance:

not specified

Control samples:

no

Species:

rabbit

Strain:

not specified

Type of coverage:

occlusive

Preparation of test site:

abraded

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 g of 75% solution of (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate in ethyleneglycol.

Duration of treatment / exposure:

4h

Observation period:

4h/24h/72h

Number of animals:

6

Details on study design:

Sample was used as supplied. A group of six albino rabbits were clipped over a wide area. One side of the animals' backs was abraded at one side with
a lancet sufficiently deep t o penetrate the stratum corneum but not enter the derma to produce bleeding.
The skin of the other side was allowed to remain intact.
A 0.5 g portion o f material was applied to an abraded and an intact skin siteon the same rabbit. Gauze patches were then placed over the treated areas
and an impervious material was wrapped snugly around the trunks of the animals t o hold the patches in place. The wrapping was removed at the end of
the four hour period and the treated areas were examined. Readings were also made after twenty-four and seventy-two hours.
The Draize method o f scoring was employed.

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 4 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Intact Skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

24 h

Score:

0.83

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Intact Skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

72 h

Score:

0.83

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Intact skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 4 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded Skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

24 h

Score:

1

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded Skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

72 h

Score:

1

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded Skin

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 4 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Intact Skin

Irritation parameter:

edema score

Basis:

mean

Time point:

24 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Intact skin

Irritation parameter:

edema score

Basis:

mean

Time point:

72 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Imtact skin

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 4 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded skin

Irritation parameter:

edema score

Basis:

mean

Time point:

24 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded skin

Irritation parameter:

edema score

Basis:

mean

Time point:

72 h

Score:

0

Max. score:

7

Reversibility:

not specified

Remarks on result:

other: Abraded skin

Interpretation of results:

GHS criteria not met

Conclusions:

75% solution of (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate in ethyleneglycol was was tested for skin irritancy in Albino Rabbits.
A single 4 h, occluded application of the test material to the skin of 6 rabbits produced no erythema or edema. 24 and 72 h observation showed minimal, barely perceptible erythema and no edema.

Executive summary:

75% solution of (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate in ethyleneglycol was was tested for skin irritancy in Albino Rabbits. A single 4 h, occluded application of the test material to the skin of 6 rabbits produced no erythema or edema. 24 and 72 h observation showed minimal, barely perceptible erythema and no edema.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (corrosive)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Solvent-free Dabco TMR Batch# meyersl.20160601

Species:

cattle

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

Three bovine corneas per group were dosed with 0.75 ml of Solvent-free Dabco TMR

Duration of treatment / exposure:

10 minutes

Duration of post- treatment incubation (in vitro):

N/A

Number of animals or in vitro replicates:

Three bovine corneas per group

Irritation parameter:

in vitro irritation score

Run / experiment:

1

Value:

34.12

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Irritation parameter:

cornea opacity score

Run / experiment:

1

Value:

15.67

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Irritation parameter:

other: Corrected Mean Optical Density

Run / experiment:

1

Value:

1.23

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Interpretation of results:

Category 2B (mildly irritating to eyes) based on GHS criteria

Conclusions:

Based on an In Vitro Irritatancy Score between 3 and 55, no prediction can be made for the UN GHS
categorization of the test article as defined in OECD Guideline #437.

According to EURL ECVAM DB-ALM Protocol No. 127, Solvent-free Dabco TMR Batch# meyersl.20160601 is considered to be a moderate eye irritant.

Reference 2

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April-June 1975

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

other: Sect ion 1500.42, - Hazardous Substances and Articles , Administration and Enforcement Regulations, Federal Register, Vol. 38, No. 187, P. 27019, 27 September 1973. .

GLP compliance:

not specified

Specific details on test material used for the study:

The sample was used as supplied.

Species:

rabbit

Strain:

not specified

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.1 ml of 75% solution of (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate in ethyleneglycol.

Duration of treatment / exposure:

The test material was not washed from the eyes.

Observation period (in vivo):

1,24,48 & 72 hrs. and 5 & 7 days

Number of animals or in vitro replicates:

6

Details on study design:

Six healthy young adult albino rabbits were used in th i s study. 0.1 gm o f the experimental material was instilled into the right eyes of the test
animals while the other eyes remained untreated t o serve as controls. The test material was not washed from the eyes.
The treated eyes were examined at 1,24,48 & 72 hrs. and 5 & 7 days following. instillation of the test material into the eyes. Interpretation o f the
results was made i n accordance with the grading system outlined in the "Illustrated Guide for Grading Eye lrritation By Hazardous Substances".

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24 h

Score:

>= 6 - <= 8

Max. score:

8

Reversibility:

not specified

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

48 h

Score:

>= 4 - <= 6

Max. score:

6

Reversibility:

not specified

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

72 h

Score:

>= 4 - <= 6

Max. score:

6

Reversibility:

not specified

Irritation parameter:

iris score

Basis:

mean

Time point:

24 h

Score:

5

Max. score:

5

Reversibility:

not specified

Irritation parameter:

iris score

Basis:

mean

Time point:

48 h

Score:

5

Max. score:

5

Reversibility:

not specified

Irritation parameter:

iris score

Basis:

mean

Time point:

72 h

Score:

5

Max. score:

5

Reversibility:

not specified

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

24 h

Score:

30

Max. score:

30

Reversibility:

not specified

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

72 h

Score:

30

Max. score:

30

Reversibility:

not specified

Interpretation of results:

Category 2 (irritating to eyes) based on GHS criteria

Conclusions:

Based on these results, Hydroxypropyl, N-2-, N,N,N-trimethylammonium 2-ethylhexanoate 75% in Ethyleneglycol is a primary ocular irritant.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)