Registration Dossier

Administrative data

Key value for chemical safety assessment

Additional information

It is understood that DTPA is capable of binding zinc, and under some circumstances in vitro, this chelation of zinc can limit its availability to dividing cells where it is used as a co-factor for enzymes involved in DNA synthesis. However in the available in vitro genotoxicity studies on DTPA acid and the potassium salt there was no evidence of mutagenicity or clastogenicity. Therefore DTPA is not considered to be genotoxic. This is consitent with other chelating agents such as Nitrilotriacetic acid, Ethylenediamine tetraacetic acid and propylene diamine tetraacetic acid which are also negative for mutagenicity (bacterial and mammalian) and clastogenicity. Specifically, in the EU risk assessment of the similar chelating agent EDTA, EDTA and its sodium salts were considered to have a low mutagenic potential only at extremely high doses. However on the basis of the various negative findings and the assumption of a threshold mode-of action for aneugens, it was concluded that EDTA and its sodium salts are not mutagenic for humans. As such it is argued that DTPA is also not mutagenic for humans based on the structural similarity of these substances.

Short description of key information:

In vitro bacterial mutation data for DTPA acid and pentapotassium DTPA; In vitro cytogenetics data (CHO assay) for pentapotassium DTPA

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

DTPA-H5 does not meet the requirements for classification for Mutagenicity as described in the Guidance on the Application of the CLP criteria, Version 4.0 (2013).