(carboxylatomethyl)dodecyldimethylammonium

Endpoint summary

Description of key information

Both in-vitro methods used suggested that this substance should be classified as a skin sensitiser.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in vitro

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: OECD Test Guideline 442E: human Cell Line Activation Test (h-CLAT)

Version / remarks:

adopted 29 Jul 2016. The study was performed using the h-CLAT method as detailed in OECD TG 442E and also in EURL ECVAM DB-ALM Protocol No. 158 (Issued 01 Jul 2015). Methodology is detailed in an XCellR8 SOP (L0094) that covers the h-CLAT. Study data is collected using XCellR8 internal protocols (IPs).

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

other: In Vitro human Cell Line Activation Test (h-CLAT) method according to OECD Test Guideline 442E.

Specific details on test material used for the study:

Supplier Colonial Chemical
Test Item Name ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt)
Supplier Code Not provided
Supplier Batch/Lot Number 55880C17
CAS Number 683-10-3
Purity 30-32%
Expiry Date 10 Mar 2019 (from CofA)
Physical State Liquid, Clear
Storage Conditions Standard (10-49˚C, closed container)
Solubility Water

Positive control results:

The CV75 (2,4-dinitrochlorobenzene (DNCB)) dose informs the dosing range selected for the CD54/86 (Nickel Sulphate) expression assay. However, in this case the highest possible dose was used which was equal to 5mg/ml (5000µg/ml). Note that Runs 4 and 5 used the same top dose however the dilution factor was adjusted (1 in 1.2 changed to 1 in 1.5) to give a greater dilution range with lower concentrations (below 1mg/ml at dilutions 5-8). This was due to low overall cell numbers observed when using high concentrations of the test item.

Key result

Parameter:

other: EC200

Value:

452

Vehicle controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of skin sensitisation

Key result

Parameter:

other: EC150

Value:

469

Vehicle controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of skin sensitisation

As Runs 2 and 3 were invalid, a repeat run was carried out (Run 4). As Run 4 was not concordant with the result from Run 1, a final run (Run 5) was required to determine the test item classification. Runs 4 and 5 were both valid and concordant. As can be seen from the data, the expression of CD54 as measured by the RFI crossed the threshold (RFI ≥200) at 6/8 concentrations used in Run 4 and 7/8 in Run 5 (yellow highlighted cells). The expression of CD86 as measured by the RFI, crossed the threshold (RFI ≥150) at 6/8 concentrations used in Run 4 and 8/8 in Run 5 (green highlighted cells). As the CD54/CD86 expression crossed the threshold for both CD54 and CD86 at non-cytotoxic concentrations, the test item is classified as a Sensitiser. Cell viability did not fall below 50% at any of the test item concentrations and therefore the result is deemed to be valid.  

For ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt) the dose that gave 75% cell viability could not be determined and therefore the maximal dose was used (5 mg/ml). The EC200 and EC150 values for CD54 and CD86 expression were 452 and 469 respectively, therefore,ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt)was classified as aSensitiseras per the prediction model

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Reference 2

Endpoint:

skin sensitisation: in vitro

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 442D (In Vitro Skin Sensitisation: ARE-Nrf2 Luciferase Test Method)

GLP compliance:

yes (incl. QA statement)

Type of study:

activation of keratinocytes

Justification for non-LLNA method:

Skin sensitisers have been reported to induce genes that are regulated by the antioxidant response element (ARE). The KeratinoSensTM test is a method for which validation studies have been completed followed by an independent peer review conducted by the European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM). The KeratinoSensTM test method was considered scientifically valid to be used as part of an IATA (Integrated Approach to Testing and Assessment), to support the discrimination between skin sensitisers and non-sensitisers for the purpose of hazard classification and labelling. The method cannot be used on its own, neither to sub-categorise skin sensitisers into subcategories 1A and 1B as defined by the UN GHS, for authorities implementing these two optional subcategories, nor to predict potency for safety assessment decisions. However, depending on the regulatory framework a positive result may be used on its own to classify a chemical into UN GHS category 1.

Specific details on test material used for the study:

Test Item Name
ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt)
Supplier Code:Not provided
Supplier batch/lot number: 55880C17
CAS number: 683-10-3
Purity: 33.7%
Active Expiry Date: 10 Mar 2019 (from Cofa)
Physical sate: Liquid, clear
Storage Conditions: Standard (10-49˚C, closed container)
Solvent: 1% DMSO in cell culture medium Administration method
In cell culture medium
Concentrations tested (μg/ml)
200, 100, 50, 25, 12.5, 6.25, 3.13, 1.56, 0.78, 0.39, 0.20, 0.10

Key result

Parameter:

other: EC1.5 value

Remarks:

Luciferase measurements and MTT viability testing were performed. The sensitisation potential of ColaTeric LAB-70UP; was quantified by calculating 2 parameters known as the EC1.5 and the IMAX value.

Value:

9.09

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of skin sensitisation

The human skin sensitisation potential of ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt) was assessed using validated in vitro method: the KeratinoSensTM test to determine keratinocyte activation. The method was adapted to animal product-free conditions by XCELLR8 and reference chemicals described in the guideline and in the performance standards were used to confirm the reliability, accuracy, sensitivity and specificity values. The adapted method showed full concordance with the Validated Reference Method (VRM) – the KeratinoSensTM standard protocol. We recently obtained clarification from the European Chemicals Agency (ECHA) that data using the adapted method may be used in REACH submissions, provided that the Performance Standards data, demonstrating equivalence with the VRM, is included in the dossier (Annex 1).

In this study, ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt) was classified as a sensitiser to human skin.

The sensitisation potential of ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt) was quantified by calculating 2 parameters known as the EC1.5 and the IMAX value. The meanings of these are as follows:

 The EC1.5 value means the Effective Concentration (EC) of test item that caused an induction of luciferase activity of greater than 1.5-fold over untreated controls. If at least one concentration induces luciferase activity to >1.5, then the product is classified as a skin sensitiser. (Note: this classification also requires the cell viability measured by MTT to be greater than 70%).

As shown in Figure 1 (Section 13.1), ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt) caused luciferase induction >1.5 in all 3 repetitions. The respective EC1.5 value were calculated as 31.72μg/ml for repetition 1; 61.87 μg/ml for repetition 2 and 9.09μg/ml for repetition 3.

Therefore, ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt) was classified as a sensitiser.

 The IMax value is the maximum-fold induction observed within the concentration range tested. Although the KeratinoSensTM test is not validated to predict potency, the IMAX value can provide a useful tool for a very preliminary comparison of sensitisation potential between test items. As shown in Section 13.1, the maximum induction was observed at a test concentration of 50μg/ml, which showed an Imax value of 1.646 in repetition 1; 1.775 at 100μg/ml in repetition 2; 1.723 at 25μg/ml in repetition 3. For reference, during test validation, sensitising proficiency chemicals produced Imax values of up to 36-fold over untreated controls.

The test concentrations of ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt) used in the KeratinoSensTM test were selected on the basis of solubility test carried out prior to the study:

Solubility of ColaTeric LAB-70UP; (1-Dodecanaminium, N-(carboxymethyl)-N,N-dimethyl-, inner salt) in cell culture medium (confirmed up to 97.9mg/ml); subsequent dilution in cell culture medium-1% DMSO giving a top concentration of 200μg/ml).

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)