Copper sulphide

Endpoint summary

Additional information

Non-human information

In vitro data

Method	Results	Remarks	Reference
bacterial reverse mutation assay (e.g. Ames test) (gene mutation) Salmonella typhimurium Strains TA98, TA100, TA1535, TA1537, TA102 (met. act.: with and without) Doses: 1.6, 8, 40, 200, 1000 µg/plate and 50, 100, 200, 400, 800 µg/plate in mutation experiments 1 and 2, respectively. OECD Guideline 471 (Bacterial Reverse Mutation Assay)	Evaluation of results: negative Test results: negative for Salmonella typhimurium Strains TA98, TA100, TA1535, TA1537, TA102(all strains/cell types tested); met. act.: with and without; cytotoxicity: yes (See additional information on results.)	1 (reliable without restriction) key study experimental result Test material (common name): Cu2+ as copper sulphate pentahydrate	Ballantyne, M. (1994)

 

The existence of two negative in vivo studies (summarised below) negates the need for in vitro mammalian cell assays.

Under normal physiological conditions, the concentration of free copper is extremely low in vivo and the majority of the copper is bound to ceruplasmin and albumin (See Section 5.1). In addition, cells contain high concentrations of potent antioxidants (e.g. glutathione). Therefore, the biological relevance of any in vitro observations would be uncertain where high concentration of the free ion would be available in cell culture growth medium. From reviews of public domain data (WHO, 1998; VRAR, 2008), there is conflicting evidence regarding the activity of copper in cell based assays for genotoxicity, however, due to the relevance of such studies in determining the genotoxicity potential of copper it is considered not appropriate or applicable to use these studies for copper and copper compounds.

In addition, due to the inappropriate level of free cupric ion present in any in vitro assays, the results of such studies will also be affected by the toxicity of the cupric ion to the mammalian cell lines.

Therefore it was considered more appropriate to review the genotoxic potential of copper and copper compounds using in vivo studies.

In vivo

Method	Results	Remarks	Reference
unscheduled DNA synthesis (DNA damage and/or repair) rat (Wistar) male oral: gavage 632.5 or 2000 mg/kg (actual ingested) equivalent or similar to OECD Guideline 486 (Unscheduled DNA Synthesis (UDS) Test with Mammalian Liver Cells in vivo)	Evaluation of results: negative Test results: Genotoxicity: negative (male); toxicity: not examined	1 (reliable without restriction) key study experimental result Test material (common name):Cu2+ as copper sulphate pentahydrate	Ward, P.J. (1994)
micronucleus assay mouse (CD-1) male/female oral: gavage 447 mg/kg EU Method B.12 (Mutagenicity - In Vivo Mammalian Erythrocyte Micronucleus Test) (Cited as Directive 2000/32/EC, B.12)	Evaluation of results: negative Test results: Genotoxicity: negative (male/female)	1 (reliable without restriction) key study experimental result Test material (common name):Cu2+ as copper sulphate pentahydrate	Riley, S.E. (1994)

 

There are additional equivocal in vivo genotoxicity studies in the public domain. However these studies do not adhere fully to OECD guidelines, have unreliable routes of administration (i.v) and are not conducted to GLP. When toxicity studies are conducted with either i.p. and i.v. routes of administration, they bypass the normal uptake and distribution mechanism that is specifically designed to protect the animal from the toxic/reactive Cu2+ ion. This invalidates these studies from regulatory decision-making procedures where the normal production and use of the chemical would not result in direct i.v. or i.p. exposure.

Therefore, these studies have been given lower quality criteria than those summarised above and should not be used for either risk assessment purposes or to classify copper compounds. However, the VRAR, 2008 provides a full review of these studies and the discussion on the unsuitability/unacceptability of these studies.

From the results above, copper sulphate pentahydrate, copper and other copper compounds are not considered genotoxic.

 

Short description of key information:
There was no evidence of mutagenic activity in Salmonella typhimurium strains in the presence or absence of the metabolic activation system when tested with copper sulphate pentahydrate. In vivo studies conducted with copper sulphate pentahydrate did not induce micronuclei in the polychromatic erythrocytes of the bone marrow of mice treated with 447 mg/kg (x2). Copper sulphate pentahydrate did not induce DNA damage according to rat hepatocyte UDS assay.
From the results above, copper and copper compounds are not considered genotoxic.

Endpoint Conclusion: No adverse effect observed (negative)