Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Additional information

Justification of the read-across from copper (II) oxide to copper sulphide:

In order to minimise animal testing, available data on copper(II) oxide have been read-across to copper sulphide (copper (II) oxide is unclassified on the basis of acute toxicity, irritation and sensitisation potential). These are both simple inorganic copper(II) compounds with very low water solubility and an anion of no toxicological concern. In fact, theoretical estimates for the solubility of copper sulphide are orders of magnitude lower than those of the oxide, ranging from 3.31E-11 µg/L to 2.4E-10 µg/L. It is generally accepted that lower water solubility can be equated to lower bioavailability and hence acute toxicity; an effect clearly seen by a comparison of copper(II) oxide toxicity with that of the more soluble copper(I) oxide. On this basis, it is considered that a read-across of the acute toxicological, irritation and sensitisation properties from copper(II) oxide to copper sulphide represents a reasonable worst-case approach, and leads to that conclusion that copper sulphide is similarly unclassified. This conclusion is supported by the fact that acute oral and irritation testing carried out with dicopper sulphide confirms that this marginally more soluble compound is also unclassified.

Skin irritation/corrosion:

A GLP-compliant skin irritation/corrosivity study was conducted in the rabbit with the read-across compound copper (II) oxide in accordance with OECD Guidelien 404 (Sanders, 2002c). No erythema or oedema was recorded in any animal at any time. It is therefore concluded that copper sulphide is not classified on the basis of skin irritation/corrosivity.

Eye irritation/corrosion:
A GLP-compliant eye irritation study was conducted in New Zealand White rabbits with the read-across compound copper (II) oxide in accordance with OECD Guideline 405 (Sanders, 2002d). Average scores for corneal opacity, iris, conjunctival redness and chemosis were 0.33, 0.22, 0.77 and 0.55 respectively. All effects were fully reversible. It is therefore concluded that copper sulphide is not classified on the basis of eye irritation/corrosivity.

Justification for classification or non-classification