Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Due to similar or lower transformation/dissolution results for tungsten trioxide (the target substance) than sodium tungstate (the source substance), the resulting toxicity potential would also be expected to be similar or lower, so read across is appropriate. In addition, read across is justified because the classification and labelling is the same or less severe for the target substance, and the PBT/vPvB profile is the same. Finally, the dose descriptors are, or are expected to be, sufficiently similar or higher for the target substance, and read-across to the source chemical is adequately protective. For more details, refer to the attached description of the read-across approach.

The following information is taken into account for acute fish toxicity for the derivation of PNEC:

No deaths were observed at the saturation concentration under exposure conditions in an acute toxicity test with tungsten trioxide; therefore, a definitive LC50 could not be determined and read-across to sodium tungstate is used for this endpoint. In a flow-through test using zebrafish and testing another soluble tungsten compound with the same classification and PBT profile (sodium tungstate) the LC50 observed was found to be greater than the highest concentration tested (>181 mg sodium tungstate/L or approximately 106 mg W/L).

Additional information