Benzoic acid, 2-hydroxy-, C14-18-alkyl derivs.

Short-term toxicity to fish

Description of key information

The LL50 to rainbow trout was determined to be in the range 100 to 300 mg/L. 

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Additional information

Two studies investigating the acute toxicity to Oncorynchus mykiss are available. Both were GLP studies conducted largely in accordance with OECD 203, using Water Accomodated Fractions of the test material. One study was conducted as a limit test and concluded the LL50 to be >1000 mg/L; the other tested nominal loading rates of 100, 300 and 1,000 mg/L and concluded the LL50 to be between 100 and 300 mg/L.

In the key GLP study based on OECD Guideline 203 and EU Method C.1, the acute toxicity of the test material to young freshwater rainbow trout (Oncorhynchus mykiss) was determined in a 96 h sealed semi-static toxicity test. Seven fingerling fish/group were exposed to nominal loading rates of 0, 100, 300 and 1000 mg/L in freshwater for up to 96 h and mortality was assessed after 3, 24, 48, 72 and 96 h. Water accommodated fractions (WAFs) of the test material were prepared, and concentrations of the test material in the WAFs were well below 1 % of the loading rate and confim its low water solubility. Test solutions were renewed at approximately 24 h intervals and the fish were not fed during the test.

The 24, 48 and 72 h LL50s were found to be in the range 300 to 1000 mg/L (nominal loading rates), whilst the 96 h LL50 was between 100 to 300 mg/L. At 300 mg/L, two fish had died within the first 24 h and all seven were dead within 96 h. No effects on mortality were noted at 100 mg/L, considered to be the 96 h no-observed-effect loading rate (NOELR) for this study.

In the supporting GLP study based on OECD Guideline 203 and EU Method C.1, a water accommodation fraction (WAF) of the test material was tested for toxicity in seven young freshwater rainbow trout (Oncorhynchus mykiss), in a semi-static test in sealed vessels with daily renewal of the test media. The WAFs were prepared at a single nominal loading rate of 1000 mg/L (48 h stirring period) and mortality was assessed after 24, 48, 72 and 96 h. WAFs used in the tests showed that concentrations of dissolved test material were less than 1 mg/L.

One fish (out of seven) exposed to the test medium died within 24 h, but no other toxic effects were seen during the 96-h observation period. The 24, 48, 72 and 96 h LL50 values were all therefore greater than 1000 mg/L (nominal loading rate), and the 96-h NOELR (no-observed-effect loading rate) can be considered to be 1000 mg/L, under the conditions of this study. However, as the exposure levels of dissolved components of the test material achieved in the WAFs were lower than expected (less than 1 mg/L) the toxicity of the test material may have been underestimated, therefore these results should be treated with caution.