Cyclohexanamine, 4,4'-methylenebis[N-(1-methylpropyl)-

Endpoint summary

Description of key information

In acute toxicity studies local irritation/corrosion is the main effect.
The LD50 value for undiluted test substance (Clearlink 1000) was 227 mg/kg bw for males.
In acute dermal studies the LD50 value was greater than 1600 mg/kg bw, but less than 2000 mg/kg bw. 
No valid data are available on acute inhalation toxicity. Clearlink 1000 has corrosive properties and no testing is required.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

227 mg/kg bw

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

discriminating dose

Value:

1 600 mg/kg bw

Additional information

Oralexposure

In a Guideline study of Kuhn et al. 2001 (EPA OPPTS 870.1100) with acceptable restrictions (no purity of test material given) 20 male and 15 female rats were gavaged with undiluted Clearlink 1000 at concentrations 100, 250, 500 and 5050 (males) and 250, 500 and 5050 (females). The post exposure period was 14 days. The estimated oral LD50 value for males is 227 mg/kg bw and 427 mg/kg bw for females. The mean oral LD50 value is 306 mg/kg bw.

In a study of Glaza et al. 1993 (comparable with EPA OPPTS 870.1100, with acceptable restrictions (no details on test material, nor of the statistical method of determining the LD50 -value) 15 male and 15 female rats were gavaged with the test material (trade name Clearlink 1000) solution in corn oil at concentrations 250, 500 and 600 (males) and 250, 400 and 500 (females). The post exposure period was 14 days. Corn oil was used as a vehicle to expand the volume administrated. The estimated oral LD50 value for males is 515 mg/kg bw and 460 mg/kg bw (females). The mean oral LD50 value is 482 mg/kg bw.

The difference in LD50 values in these two studies is likely caused by the method of administration. In a study of Kuhn et al. (2001) the test substance was administered without vehicle while the study of Glaza et al. (1993) was conducted with corn oil as a vehicle. It is likely, that corn oil delayed the absorption of test material from the GI tract resulting lower LD50 values. The study of Kuhn et al. (2001) was selected as a key study and the result is used as a key value for hazard assessment and classification and labeling.

Dermal exposure

In a Guideline study of Kuhn et al. 2005 (OECD 402) with acceptable restrictions (less than required 3 dose levels used) 10 male and 10 female rats were treated with undiluted Clearlink 1000 at concentrations 1600 and 2000 mg/kg bw on unharmed skin of the dorsal trunk not less than 10% of the total body surface area, in a semi-occlusive conditions for 24 h. The readings were made at 60 minutes, 4, 7, 11 and 14 days after removal of the wrappings. The post exposure period was 14 days. The acute dermal LD50 value is greater than 1600 mg/kg bw but less than 2000 mg/kg bw. This study was selected as a key study and the result is used as a key value in hazard assessment and classification and labeling.

In a limit test of Kuhn et al. 2005 (according to Guidelines OECD 402 and EPA OPPTS 870.1200) with acceptable restrictions (administered dose was less than 2000 mg/kg bw) 5 males and 5 females were treated with undiluted Clearlink 1000 at 1000 mg/kg bw on unharmed skin of the dorsal trunk not less than 10% of the total body surface area in a semi-occlusive conditions for 24 h.

The readings were made at 60 minutes, 4, 7, 11 and 14 days after removal of the wrappings. The post exposure period was 14 days. The acute dermal LD50 value is greater than 1000 mg/kg bw.

Inhalation exposure

No valid data are available on acute inhalation toxicity. According to column 2 of REACH Annex VIII Section 8.5, no testing required, because Clearlink 1000 has corrosive properties.

Justification for classification or non-classification

Clearlink 1000 is classified Xn; R21/22 according to Annex VI of Regulation 67/548/EEC and Acute Tox.3 (oral) and Acute Tox.4 (dermal) according to Annex I of Regulation (EC) No 1272/2008.