Hexane-1,2,6-triol

Endpoint summary

Description of key information

The read-across approach conducted by the QSAR toolbox based on a comparison to the five identified nearest neighbors resulted in a negative prediction for the target chemical for the predicted endpoint EC3 (estimated concentration needed to produce a stimulation index of 3) in the in vivo LLNA.

A supporting QSAR analysis using Derek revealed a "nothing-to-report" result as the test item did not activate an alert or reasoning rule. For the endpoint of skin sensitisation, ‘nothing to report’ may be extrapolated to a negative prediction. Thus, the Derek prediction gives a strong hint for the absence of skin sensitizing properties of the test item and supports the negative read-across prediction of the QSAR toolbox.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
Read-across source entries were selected by analysis with the QSAR toolbox. The toolbox prediction report is attached to this study record.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The analysis by the QSAR toolbox delivers the nearest neighbors (i.e. analogues) to the target chemical based on structural and functional similarities. The profile "Organic functional groups" with the target groups "alcohol" and " alkane, branched with secondary carbon" was used for the primary grouping. For subcategorization the profile "Protein binding by OASIS" with the target "No alert found" was used. A further subcategorization with the profile "Organic functional groups, nested" with the target groups "alcohol" and " alkane, branched with secondary carbon" and "overlapped groups" delivered the described five nearest neighbors that were used for the read-across analysis. The resulting group of chemicals is a structural homogenous group with no alerts for protein binding, and the target chemical is in domain of all profiles used so that the resulting prediction has a high level of confidence.


2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
In addition to the information on source and target chemicals provided in the test material sections and the data matrix by the QSAR toolbox, which is attached to this study record, information on basic substance properties are given here. Target and source chemicals are small molecules with a high water solubility and a low logPow.

TARGET:
1,2,6-Hexanetriol:
CAS No: 106-69-4
Molecular weigth: 134.17 Da
Water solubility: > 2000 g/L
logPow: -0.77 (predicted value, source EPISuite)

SOURCE:
Glycerol:
CAS No: 56-81-5
Molecular weigth: 92.094 Da
Water solubility: 1000 g/L (experimental and predicted value, source EPISuite)
logPow: -1.75 (experimental value); -1.65 (predicted value, source EPISuite)

SOURCE:
Isopropanol:
CAS No: 67-63-0
Molecular weigth: 60.095 Da
Water solubility: miscible with water (experimental value, source ChemSpider); 402.4 g/L (predicted value, source EPISuite)
logPow: 0.28 (predicted value, source EPISuite)

SOURCE:
Propylene glycol:
CAS No: 57-55-8
Molecular weigth: 76.094 Da
Water solubility: miscible with water (experimental value, source ChemSpider); 811.1 g/L (predicted value, source EPISuite)
logPow: -1.07 (experimental value); -0.78 (predicted value, source EPISuite)

SOURCE:
3-Isopropoxy-1,2-propanediol:
CAS No: 17226-43-6
Molecular weigth: 134.174 Da
Water solubility: 141.5 g/L (predicted value, source EPISuite)
logPow: -0.24 (predicted value, source EPISuite)

SOURCE:
2-Undecanol:
CAS No: 1653-30-1
Molecular weigth: 172.308 Da
Water solubility: 49.73 mg/L (predicted value, source EPISuite)
logPow: 4.21 (predicted value, source EPISuite)


3. ANALOGUE APPROACH JUSTIFICATION
The in vivo LLNA studies conducted with the five nearest neighbors, which are structurally similar and have similar physico-chemistry properties, show a unique pattern. All are clearly negative and did not show any potential for skin sensitzation. Thus, it can be concluded with a high level of confidence that the skin sensitization potential of the target chemical is adequately adressed with this read-across approach.


4. DATA MATRIX
Read-across source entries building the data matrix were selected by analysis with the QSAR toolbox. The toolbox data matrix is attached to this study record.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

GLP compliance:

no

Type of study:

mouse local lymph node assay (LLNA)

Parameter:

other:

Remarks on result:

no indication of skin sensitisation based on QSAR/QSPR prediction

The read-across approach conducted by the QSAR toolbox based on a comparison to the five identified nearest neighbors resulted in a negative prediction for the target chemical for the predicted endpoint EC3 (estimated concentration needed to produce a stimulation index of 3) in the in vivo LLNA.

Interpretation of results:

GHS criteria not met

Conclusions:

The read-across approach conducted by the QSAR toolbox based on a comparison to the five identified nearest neighbors resulted in a negative prediction with high confidence for the target chemical for the predicted endpoint EC3 in the in vivo LLNA. Thus, according to Regulation (EC) 1272/2008, the data are conclusive but not sufficient for classification.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The read-across approach conducted by the QSAR toolbox based on a comparison to the five identified nearest neighbors resulted in a negative prediction with high confidence for the target chemical for the predicted endpoint EC3 in the in vivo LLNA. Thus, according to Regulation (EC) 1272/2008, the data are conclusive but not sufficient for classification.