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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Short-term toxicity to fish:

As no data are available on gadolinium oxalate, an analogy was made with the related substance gadolinium oxide. The study performed with this read across substance (Bazzon, 2000) did not observe any adverse effects in fish up to and including at the highest nominal concentration tested, i.e. 100 mg Gd2O3/L (equivalent to 159.6 mg/L anhydrous gadolinium oxalate). Consequently, and by analogy with gadolinium oxide, gadolinium oxalate is considered not to be harmful to fish.

 

Short-term toxicity to aquatic invertebrates:

An acute toxicity study in daphnids (Ablitt, 2017) demonstrated that gadolinium oxalate did not cause any adverse effects in daphnids exposed to a saturated solution with a nominal loading rate of 100 mg/L. Based on the results of this study, gadolinium oxalate should not be considered as harmful to aquatic invertebrates.

 

Toxicity to aquatic algae and cyanobacteria: 

For algae, all available data for both water soluble, sparingly soluble, and insoluble rare earth compounds have been summarised and thoroughly evaluated in the document attached to IUCLID Section 13. In this expert statement, it is concluded that there is no scientific added value in the performance of further algal growth inhibition studies with rare earth compounds. For insoluble and sparingly soluble rare earth compounds, EC50 values (loading rate-based) were consistently > 100 mg/L (or > 100% v/v of a saturated solution with nominal loading rate 100 mg/L). Based on this information, gadolinium oxalate can be concluded not to be harmful to algae either.

Toxicity to aquatic microorganisms:

Finally, based on water solubility and exposure considerations, it is considered very unlikely that gadolinium oxalate would be hazardous to aquatic microorganisms and/or pose risks for adverse effects to occur in microorganisms in biological sewage treatment plants. Therefore, it was considered not necessary to perform an activated sludge respiration inhibition test with gadolinium oxalate.

Additional information