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Administrative data

Key value for chemical safety assessment

Additional information

Results of the Ames test and the in vivo micronucleus test were negative; the results of the in vitro CA test were ambiguous. In the latter test, PDTA-FeNH4 showed some evidence of clastogenic activity in the absence of S-9 mix, but only at a single, toxic concentration. At this same concentration, there were indications of an effect of PDTA-FeNH4 on spindle formation or function. There was also limited evidence of weak clastogenic activity in the presence of S-9 mix, but again only at the highest concentration tested.

The long treatment period together with the high concentration of the chelant may have resulted in exchange and substantial binding of essential elements such as zinc. Heimbach et al (2000; see robust summary) concluded that the lack of effects by the Zn-EDTA salt in contrast to effects induced by Ca-, Na- and Mn-salts of EDTA, provided evidence that zinc is required for the initiation or continuation of DNA synthesis and maintaining cell function. As such, the significance of mutations produced by EDTA-FeNa (see Heimbach et al., 2000) and PDTA-FeNH4 (this study) at non-physiological concentrations in an in vitro screening system is difficult to extrapolate for relevance to intact organisms.

Therefore, the overall findings indicate that PDTA-FeNH4 lacks significant genotoxic potential under conditions that do not deplete essential trace elements required for normal cell function.


Short description of key information:
The following studies are available: Ames test, in vitro chromosome aberration test and an in vivo mouse micronucleus test.

Endpoint Conclusion:

Justification for classification or non-classification

The test substance gave negative results in one in vitro mutagenicity test, viz. the Ames test, and in one in vivo mutagenicity test, viz. the micronucleus test. It gave ambiguous results in the in vitro chromosome aberration test (at a high, cytotoxic concentration). The latter was most probably explained by induction of Zn deficiency. Overall, it was concluded that classification for genotoxicity is not warranted.