Quaternary ammonium compounds, trimethylsoya alkyl, chlorides

Endpoint summary

Description of key information

Based on the results of the read across study, TMAC S is considered to be corrosive to skin and eyes.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation: in vivo

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Justification for type of information:

Refer to the Quaternary ammonium salts (QAS) category or section 13 of IUCLID for details on the category justification.

Reason / purpose for cross-reference:

read-across source

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

not specified

Species:

rabbit

Strain:

New Zealand White

Type of coverage:

occlusive

Preparation of test site:

other: intact and abraded

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.5 mL of undiluted test substance (50% pure)

Duration of treatment / exposure:

4 or 1 h

Observation period:

4 or 1 hour, 48 h and 10 days

Number of animals:

Six males and females

Details on study design:

Six healthy adult New Zealand White albino rabbits (M/F) were used for the test. 24 hours prior to applying the test substance, the hair was removed from the back of the animals with electric clippers in such a way as to avoid abrasions.

An amount of 0.5 mL of the undiluted test substance was brought on the intact skin under a surgical patch measuring 1 x 1 inch. The patches were fixed to the application site by means of adhesive tape and the entire trunk of the rabbits was wrapped with an impervious material to maintain the test patches in position and to retard evaporation of volatile substances.

Each rabbit was treated on the intact skin. The abrasions were minor incisions through the stratum corneum, but not sufficiently deep to disturb the derma or to produce bleeding.

After an exposure period of 4 or 1 hour the patches and the test substance applied were removed and the resulting skin reactions were evaluated by the method of Draize scoring. A second reading was made 48 hours later.

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 1 h

Score:

0.85

Max. score:

8

Reversibility:

fully reversible within: 10 days

Remarks on result:

other: Study II, following exposure period of 1 hour

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 4 h

Score:

4

Max. score:

8

Reversibility:

not reversible

Remarks:

within 10 days

Remarks on result:

other: Study I, following exposure period of 4 hours

Irritation parameter:

erythema score

Remarks:

4 h exposure

Basis:

mean

Time point:

48 h

Score:

3.84

Max. score:

4

Reversibility:

not fully reversible within: 10 days

Remarks on result:

other: well-defined to moderate erythema

Irritation parameter:

erythema score

Remarks:

1 h exposure

Basis:

mean

Time point:

48 h

Score:

1.08

Max. score:

4

Reversibility:

fully reversible within: 10 days

Remarks on result:

other: very slight to moderate erythema

Irritation parameter:

edema score

Remarks:

1 h exposure

Basis:

mean

Time point:

48 h

Score:

ca. 0.33

Max. score:

4

Reversibility:

fully reversible within: 10 dys

Remarks on result:

other: very slight to slight edema

Irritation parameter:

edema score

Remarks:

4 h exposure

Basis:

mean

Time point:

48 h

Score:

ca. 1.58

Max. score:

4

Reversibility:

not fully reversible within: 10 days

Remarks on result:

other: very slight or slight edema

Irritation parameter:

overall irritation score

Remarks:

4 h exposure

Basis:

mean

Time point:

48 h

Score:

ca. 5.4

Max. score:

8

Reversibility:

not reversible

Remarks:

within 10 days

Remarks on result:

other: Corrosive to skin

Irritation parameter:

overall irritation score

Remarks:

1 h exposure

Basis:

mean

Time point:

48 h

Score:

ca. 1.25

Max. score:

8

Reversibility:

fully reversible within: 10 days

Remarks on result:

other: corrosive to skin

Irritation parameter:

erythema score

Basis:

mean

Time point:

24 h

Remarks on result:

not measured/tested

Irritation parameter:

erythema score

Basis:

mean

Time point:

72 h

Remarks on result:

not measured/tested

Irritation parameter:

edema score

Basis:

mean

Time point:

72 h

Remarks on result:

not measured/tested

Irritation parameter:

edema score

Basis:

mean

Time point:

24 h

Remarks on result:

not measured/tested

Irritant / corrosive response data:

Observations in 4 hours test:
- After 4 hours: Very slight to well-defined erythema, very slight ischemia and very slight edema
- After 48 hours: Well-defined to moderate erythema, very slight to slight ischemia and very slight or slight edema
- After 10 days: Slight to distinct incrustation and decreased hair growth

Observations in 1 h test:
After 1 h: Very slight erythema
After 48 h: Very slight to moderate erythema and very slight or slight edema
After 10 d: No skin effects were observed

For result tables, kindly refer to the attached background material section of the IUCLID.

Interpretation of results:

other: Category 1C based on CLP criteria

Conclusions:

Based on the results of the read across study, the undiluted test substance is considered to be corrosive to skin.

Executive summary:

A study was conducted to determine the skin irritation potential of the read across substance, TMAC T (50% active) in rabbits, according to a method similar to OECD Guideline 204. Six rabbits (both sexes) were treated with 0.5 mL of undiluted read across substance (50% active ingredient) in an occlusive patch fixed with adhesive tape and wrapped with an impervious material, for 4 h. Observations were made at 4 h, 48 h and 10 days post-exposure. If the read across substance appeared to be corrosive after 4 h, another study was conducted with a 1 h exposure period under similar test conditions. The Draize scoring criteria was used for evaluating the corrosion potential. At 4 h, very slight to well-defined erythema, very slight ischemia and very slight oedema were observed, with an average irritation score of 4/8. At 48 h, there was well-defined to moderate erythema, very slight to slight ischemia and very slight or slight oedema and the average irritation score was 5.4/8. After 10 days, slight to distinct incrustation and decreased hair growth was observed. After an exposure period of 1 h, very slight erythema was observed with an average irritation score of 0.85/8. After 48 h, there was very slight to moderate erythema and very slight or slight oedema and the average irritation score was 1.25/8. No skin effects were observed after 10 days. Under the study conditions, the undiluted read across substance (50% active ingredient) was corrosive after 4 h of occlusive exposure. Based on the results of the read across study, similar corrosive potential is expected for the test substance.

Reference 2

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From February to November 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

GLP compliance:

yes

Test system:

human skin model

Remarks:

In Vitro Reconstituted Human Epidermis Model , Episkin

Source species:

human

Cell type:

non-transformed keratinocytes

Vehicle:

water

Remarks:

sterile water

Control samples:

yes, concurrent vehicle

yes, concurrent positive control

Amount/concentration applied:

60.3% and 3.015% active ingredient. (The diluted concentration (i.e. 3.015%) is equivalent to the maximum on-head hair colorant usage concentration).

Duration of treatment / exposure:

15 minutes

Duration of post-treatment incubation (if applicable):

42 +/- 1 hour

Number of replicates:

3 (tissues)

Irritation / corrosion parameter:

% tissue viability

Remarks:

mean value

Run / experiment:

Undiluted (i.e., equivalent to 60.3% a.i.)

Value:

ca. 106.3

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: standard deviation: 4.8

Irritation / corrosion parameter:

% tissue viability

Remarks:

mean value

Run / experiment:

5% in sterile water (i.e., equivalent to 3.015% a.i.)

Value:

ca. 121.3

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: standard deviation: 1.1

Other effects / acceptance of results:

Positive control: 15.6 +/- 5.3% of viability and complete necrosis in the 3 tissues

Results (details):

When applied neat and at a concentration of 5% (equivalent to 60.3% and 3.015% active ingredient), no cytotoxicity was induced. Relative mean viability was 106.3 ± 4.8% for the undiluted material and 121.3 ± 1.1% for the diluted material. Histological evaluation showed no to minimal epidermal effects with the 5% (3.015% a.i.) solution. The neat material also resulted in no to minimal epidermal effects in two tissues, with the third tissue showing slight epidermal effects. In general, the histopathological evaluation confirmed the absence of cytotoxicity in the MTT section of the study at both concentrations.

Absorbance Results

Treatment	Tissue	Individual absorbance values
Undiluted	1	0.847	0.797
	2	0.764	0.741
	3	0.789	0.771
5% in sterile water	1	0.924	0.886
	2	0.937	0.844
	3	0.905	0.878
Negative control	1	0.800	0.758
	2	0.751	0.739
	3	0.662	0.718
Positive control	1	0.129	0.131
	2	0.068	0.072
	3	0.155	0.136

 

Optical Density and Viability Results

Treatment	Individual OD540values	Mean OD540	Standard deviation	Relative individual tissue viability	Relative mean viability %	Standarddeviation
Undiluted	0.822	0.785	0.035	111.4	106.3	4.8
	0.752			101.9
	0.780			105.7
5% in sterile water	0.905	0.895	0.008	122.6	121.3	1.1
	0.890			120.6
	0.891			120.7
Negative control	0.779	0.738	0.045	105.6	100	6.4
	0.745			100.9
	0.690			93.5
Positivecontrol	0.130	0.115	0.040	17.6	15.6	5.3
	0.070			9.5
	0.145			19.6

 

Histology summary:

Treatment	Tissue	Histological observations*
Undiluted	1	Comparable to negative control - grade 0
	2	Loss of granulation among stratum granulosum cells – grade 1
	3	Minimal vacuolation of cells in all layers of the epithelium – grade 1
5% in sterile water	1	Slight vacuolation of cells in all layers of the epithelium – grade 2
	2	Comparable to negative control - grade 0
	3	Minimal vacuolation of cells in all layers of the epithelium – grade 1
Negative control	1	Grade 0 in 3/3 samples
	2
	3
Positivecontrol	1	Complete necrosis in 3/3 samples
	2
	3

 

*Grading scale for histological observationsGrade 0 = Absence of any epithelial changes

Grade 1 = Minimal cellular alterations characterised by loss of granulation of cells in the stratum granulosum, isolated nectrotic cells of cytoplasmic vaculation of superficial cells

Grade 2 = Moderate numbers of necrotic or vacuolated cells more especially in surface layers.

Grade 3 = Marked number of necrotic or vacuolated cells at all levels including basal layer with loss of cell boundaries, orientation and nuclear detail

Grade 4 = Complete degeneration/necrosis of all cell layers

Interpretation of results:

other: CLP Category 2, not warranted

Conclusions:

Under the study conditions, the test substance was determined to be slightly irritating to the skin in the in vitro Episkin model.

Executive summary:

A study was conducted to determine the in vitro skin irritant potential of the test substance, TMAC S (60.3% active), according OECD guideline 439 (In Vitro Reconstituted Human Epidermis Model, Episkin), in compliance with GLP. The test substance was applied undiluted as well as 5% v/v solution in sterile water (i.e., equivalent to 60.3 and 3.015% a.i.). Tissues were exposed to the test substance for 15 minutes followed by a 42 h observation period. No cytotoxicity was induced at both the test concentrations. The relative mean viability was 106.3 ± 4.8% for the undiluted material and 121.3 ± 1.1% for the diluted material. Histological evaluation showed no to minimal epidermal effects with the 5% (3.015% a.i.) solution. The neat material also resulted in no to minimal epidermal effects in two tissues, with the third tissue showing slight epidermal effects. In general, the histopathological evaluation confirmed the absence of cytotoxicity in the MTT section of the study at both concentrations. Under the study conditions, the test substance was concluded to be slightly irritating to the skin (SCCS, 2012).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (corrosive)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin

A study was conducted to determine the skin irritation potential of the read across substance, TMAC T (50% active) in rabbits, according to a method similar to OECD Guideline 204. Six rabbits (both sexes) were treated with 0.5 mL of undiluted read across substance (50% active ingredient) in an occlusive patch fixed with adhesive tape and wrapped with an impervious material, for 4 h. Observations were made at 4 h, 48 h and 10 days post-exposure. If the read across substance appeared to be corrosive after 4 h, another study was conducted with a 1 h exposure period under similar test conditions. The Draize scoring criteria was used for evaluating the corrosion potential. At 4 h, very slight to well-defined erythema, very slight ischemia and very slight oedema were observed, with an average irritation score of 4/8. At 48 h, there was well-defined to moderate erythema, very slight to slight ischemia and very slight or slight oedema and the average irritation score was 5.4/8. After 10 days, slight to distinct incrustation and decreased hair growth was observed. After an exposure period of 1 h, very slight erythema was observed with an average irritation score of 0.85/8. After 48 h, there was very slight to moderate erythema and very slight or slight oedema and the average irritation score was 1.25/8. No skin effects were observed after 10 days. Under the study conditions, the undiluted read across substance (50% active ingredient) was corrosive after 4 h of occlusive exposure. Based on the results of the read across study, similar corrosive potential is expected for the test substance.

 

An OECD 439 guideline compliant in vitro skin irritation study on the test substance was identified to be reported in a SCCS opinion on Soytrimonium chloride (Colipa no. 72). In this study, the test substance (active: 60.3%) was applied undiluted as well as 5% v/v solution in sterile water (i.e., equivalent to 60.3 and 3.015% a.i.) in an in vitro Reconstituted Human Epidermis Model (Episkin). Tissues were exposed to the test substance for 15 minutes followed by a 42 h observation period. No cytotoxicity was induced at both the test concentrations. The relative mean viability was 106.3 ± 4.8% for the undiluted material and 121.3 ± 1.1% for the diluted material. Histological evaluation showed no to minimal epidermal effects with the 5% (3.015% a.i.) solution. The neat material also resulted in no to minimal epidermal effects in two tissues, with the third tissue showing slight epidermal effects. In general, the histopathological evaluation confirmed the absence of cytotoxicity in the MTT section of the study at both concentrations. Under the study conditions, the test substance was concluded to be slightly irritating to the skin (SCCS, 2012). The results from the in vitro test are considered to be questionable as the RHE test model are recognised to be not applicable for all groups of chemical classes specifically for the fatty amine derivatives, where RhE assays did not predict corrosivity, whereas these substances were corrosive in in vivo rabbit studies (Houthoff et al., 2014 cited in the ECHA R.7a guidance, 2017).

 

Based on the above information and the results from the in vivo read across study, the test substance is considered to be corrosive to skin.

 

 

Eye

Data waiving: A study does not need to be conducted because the substance is classified as skin corrosion, leading to classification as serious eye damage (Category 1).

 

This is further supported by an OECD 438 guideline compliant in vitro eye irritation study on the test substance which was identified to be reported in a SCCS opinion on Soytrimonium chloride (Colipa no. 72). In this study, isolated chicken eyes were exposed to the test substance for 10 seconds, which were followed by evaluations at 0, 30, 75, 120, 180 and 240 minutes. The test substance was applied on cornea either undiluted or at a concentration of 5% (i.e., equivalent to 60.3 and 3.015% a.i.). The undiluted test substance produced severe irritation with an irritation index of 141/200. Histological examination of the corneas revealed moderate erosion of the epithelium with no effects on the stroma and endothelium being observed. The 5% (v/v) aqueous dilution of the test substance caused very slight swelling (5%), slight opacity (1.0) and slight to moderate fluorescein retention (1.5). The calculated Irritation Index was 55/200. Histological examination of the corneas treated with the diluted material revealed very slight or slight erosion of the epithelium, with no effects on the stroma and endothelium being observed. Under the study conditions, the undiluted test substance induced irreversible effects on the eye and serious damage to the eye, while the 5% (v/v) aqueous dilution was evaluated to cause only minimal or transient irritation. Therefore, the test substance was concluded to be corrosive to eyes (SCCS, 2012).

Justification for classification or non-classification

Based on the results of thein vivoskin and eye irritation studies, the test substance warrants a ‘Skin Corr. 1C; H314: Causes severe skin burns and eye damage’ as well as serious eye damage, ‘Eye dam. 1; H31: Causes serious eye damage’ classification according to the EU CLP criteria (Regulation EC 1272/2008). Labelling for this endpoint is covered by the above classifications for skin effects. 

With regard to respiratory tract irritation, although TMAC S is a very corrosive substance, its low vapour pressure prohibits the occurrence of respiratory irritation by vapour. Further, the classification of corrosive is already considered to implicitly cover the potential of RTI; therefore an additional Cat.3 is considered to be superfluous (Guidance CLP Ch. 3.8.2.5).