Phenol, heptyl derivs.

Short-term toxicity to fish

Description of key information

The acute toxicity of the test item to the freshwater fish rainbow trout (Oncorhynchus mykiss) has been investigated and gave a 96-Hour LL*50value of 2.4 mg/l loading rate WAF with 95% confidence limits of 1.8 – 3.2 mg/l loading rate WAF. The No Observed Effect Loading rate was 1.8 mg/l loading rate WAF.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

2.4 mg/L

Additional information

There is one key and one supporting acute toxicity study on fish.

The key study was performed to assess the acute toxicity of the test item to rainbow trout (Oncorhynchus mykiss). The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No 203 and Method C.1 of Commission Regulation (EC) No. 440/2008.

Following preliminary range-finding tests, fish were exposed, in groups of seven, to Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates of 1.0, 1.8, 3.2, 5.6 and 10 mg/l for a period of 96 hours at a temperature of approximately 14°C under semi-static test conditions. The number of mortalities and any sub-lethal effects of exposure in each test and control vessel were determined 2 and 6 hours after the start of exposure and then daily throughout the test until termination after 96 hours.

Chemical analysis of the 1.8, 3.2, 5.6 and 10 mg/l loading rate WAFs showed measured concentrations to range from 0.0250 to 8.67 mg/l at 0 hours (fresh media) and 0.00972 to 8.09 mg/l at 24 hours (old media). Analysis of the 1.8 mg/l loading rate WAF at 72 (fresh media) and 96 hours (old media) showed measured concentrations of 0.0808 and 0.0543 mg/l respectively.

The dissolved test item may have been one or several components of the test item. Given that toxicity cannot be attributed to a single component or mixture of components but to the test item as a whole, the results were based on nominal loading rates only.

The acute toxicity of the test item to the freshwater fish rainbow trout (Oncorhynchus mykiss) has been investigated and gave a 96-Hour LL*₅₀value of 2.4 mg/l loading rate WAF with 95% confidence limits of 1.8 – 3.2 mg/l loading rate WAF. The No Observed Effect Loading rate was 1.8 mg/l loading rate WAF.

 

In a supporting study the acute toxicity of the substance to Atlantic cod (Gadus morhua L.) was reported in the publication: Environmental Toxicology and Chemistry, Vol. 17, No. 4 pp. 740 -746, 1998. Title: Acute Toxicity and Toxicokinetics of 4 -Heptylphenol in Juvenile Atlantic Cod (Gadus Morhua L.) Authors: Tollefsen KE, Ingerbrigtsen K, Olsen AJ, Zachariassen, KE & Johnsen S.

The study was performed under flow through conditions. Fish were exposed to the test substance for 168 h at nominal concentrations of 0.5, 1, 2.1, 4.2 umol/L. and a loading of 5.7 g fish/L.

The 168 h LC50 was 2.7 umol/L (or 0.52 mg/L) . The 96 h LC50 was estimated by interpolation to be 2.9 umol/L (or 0.56 mg/L). Control groups, exposed to methanol alone showed no mortality.