Document MJN6pp8qxyRKe2VZMmqKE9jRL

Telomer Research Program AR226-1421 Report Title: 1-Decanol, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluoroAlga, Growth Inhibition Test with Scenedesmus subspicatus, 72h, Limit Test with the Water Accommodated Fraction (WAF) Author(s): Dirk Scheerbaum OPPT NCIC 2003 July 18 12:00PM Contractor: Dr. U. Noack-Laboratorium fr Angewandte Biologie (Sarstedt, Germany) Study Completion Date: 07-August-2002 Study Objective: To determine the effects of the water accommodated fraction of 1-Decanol, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluoro-, on growth rate and biomass of the unicellular freshwater green alga Scenedesmus subspicatus according to the principles of OECD Guideline 201. Materials and Methods: The study was conducted under static conditions over 72 hours with an initial cell density of nominally 104cells/mL and a water accommodated fraction as limit concentration containing 0.47 mg/L of the test substance. The test vessels were pre-coated with the test substance for 14 days (23 2 C) before the initiation of the test. At the end of the pre coating period the flasks were emptied and used for the test. For the preparation of the water accommodated fraction (WAF), a suspension with a nominal loading of 100 mg/L was shaken for 96 hours. Three replicates were tested at the limit test concentration with 6 replicates of the control. Cell density was measured via Chlorophyll-a-fluorescence at the beginning of the test and every 24 hours during the test. No self-fluorescence was found in the water accommodated fraction. The limit test concentration and control was analyzed for the test substance by gas chromatography with mass spectrometric detection at test start and test end. The growth rate, the inhibition of biomass and the rate related inhibition after 72 h were calculated from the cell density values. One-way ANOVA and Dunnett's test of growth rate and biomass integrals, respectively, were carried out for the determination of statistically significant differences compared to control replicates. Findings: The effects of 1-Decanol, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluoro- based on the initial measured test substance concentration are summarized in Table 1. Microscopic evaluation of the cells at the start and end of the incubation period revealed no morphological abnormalities. At the end of the test, the concentration of the test substance was below the detection limit of 0.009 mg/L. Does not contain TSCA CBI 1 TRP (5-June-03) Table 1: NOEC/LOEC and EC50 Values (0-72 h) for Biomass Inhibition and Rate Related Inhibition Eb C50 95 % confidence interval LOEC NOEC Er C50 95% confidence interval LOEC NOEC Inhibition of biomass growth [mg/Ll >0.47 Not applicable >0.47. 0.47 Rate-related inhibition [mg/L] >0.47 Not applicable >0.47 0.47 Conclusion: In this study, the water accommodated fraction containing 0.47 mg/L of 1Decanol, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluoro-, based on initial measured concentrations, was found not to inhibit the growth of the freshwater green alga Scenedesmus subspicatus. Does not contain TSCA CBI 2 TRP (5-June-03)