Registration Dossier

Administrative data

Description of key information

In general LD50 values in oral acute studies are between 150 mg/kg and 1660 mg/kg. Only limited data are available concerning acute dermal toxicity. The lowest LD50 reported in the literature is 275 mg/kg. Cyclohexylamine is of low acute inhalation toxicity.

Key value for chemical safety assessment

Additional information

There are several studies reported in the literature concerning the acute oral toxicity of cyclohexylamine. Most studies suffer from limitations in documentation. With one exception in the rat, LD50 values are in the range of 150 mg/kg up to 1660 mg/kg. Effects were local for the most part, although the liver, heart, lungs and kidneys were also affected. In the mouse the LD50 values were >680 mg/kg.

There are no reliable studies available to evaluate acute dermal or inhalation toxicity. All available information is summarized in a weight-of-evidence approach below. Since cyclohexylamine meets the criteria for classification as a corrosive compound no further testing should be done according ANNEX VII column 2 of the REACH regulation.

In rabbits an LD50 of 275 mg/kg was reported after dermal appliocation in an early study with insufficient documentation (Smyth et al. 1969). In another study a single application of different amounts of undiluted cyclohexylamine to the back of rabbits for 24 hours was investigated and observation for mortality and signs of intoxication was recorded for 14 days. A precise LD50 value was not determined but the range was within 631 and 1000 mg/kg bw (Randall et al., 1990).

There are no reliable studies available conducted according to recent guidelines to evaluate the acute inhalation toxicity. LD50 values reported in early studies with limitations in documentation and no detailed information on the testing atmosphere reported, with one exception, LD50 values > 700 mg/m3 to 60000 mg/m3. Based on a weight-of-evidence evaluation it can be concluded that cyclohexylamine is of low acute inhalation toxicity.

Justification for classification or non-classification

Classification of cyclohexylamine is based on all available information; according to the EU classification criteria 67/548/EWG Annex 1 the compound is classified with R21/R22. According to EU regulation no. 1272/2008 (GHS) we would propose acute oral toxicity cat 3 and acute dermal toxicity cat 3.