Benzaldehyde, 2-hydroxy-5-nonyl-, oxime, branched

Endpoint summary

Additional information

Short-term toxicity

GLP guideline studies evaluating the short-term toxicity of Benzaldehyde, 2-hydroxy-5-nonyl, oxime, branched (C9 Aldoxime, CAS 174333-80-3, including all impurities) to three trophic levels (fish, invertebrates, algae) are available. The test results indicate that the test substance is acutely toxic to aquatic organisms and that fish are more sensitive than algae and invertebrates.

The toxicity of the test substance to microorganisms was evaluated in a study according to OECD guideline 209 under GLP conditions. In a static study domestic activated sludge was exposed for 3h. The EC50 is determined to be > 1000 mg/L, while the respective EC10 is determined to be 200.4 mg/L based on nominal concentrations. Based on this result it can be concluded that the inhibition of the degradation activity of activated sludge is not anticipated when introduced to biological treatment plants in appropriate low concentrations.

 

Long-term toxicity

Long-term tests evaluating the chronic toxicity of Benzaldehyde, 2-hydroxy-5-nonyl, oxime, branched (CAS 174333-80-3) to all three trophic levels (fish, invertebrates, algae) are available. The test results indicate that the test substance is very toxic to aquatic organisms based on long-term exposure and confirm fish to be more sensitive than algae and invertebrates.

The key study used for the PNEC derivation investigated the long-term toxicity of the test substance to early life stage of zebra fish (Danio rerio) under flow through conditions according to GLP and OECD guideline 210 (BASF 2019). Based on measured concentrations a 34d-NOEC is determined to be 4.27 µg/L for hatching success. 

 

Endocrine mode of action

No study is available focusing on potential effects of Benzaldehyde, 2-hydroxy-5-nonyl, oxime, branched based on an endocrine mode of action. However, various studies are available investigating endocrine disrupting effects of 4-nonylphenol in fish and invertebrates (see ECHA 2012, SVHC Support Document). In general, effects occur in the range of 1 to 10 µg/L. Based on the toxicity pattern as well as the available binding assays it can be concluded that the effect values will not be lower for the C9 Aldoxime Thus, the PNEC value derived for freshwater and marine water on the basis of the long-term toxicity fish test is considered to be sufficiently low to cover effects related to this specific mode of action.