Document ExEJq3LROx78r6ggGGvyV7JQN

p. 1 ACUTE TOXICITY TO THE MIDGE (CHIRONOMUS TENTANS) TEST SUBSTANC E Identity : Perfluorooctanoic acid, ammonium salt ; may also be referred to as PFOA, PFOA ammonium salt, Ammonium perfluorooctanoate, FC-116, FC-126, FC-169, or FC-143 . (Octanoic acid, pentadecafluoro-, ammonium salt, CAS # 382526-1 ) Remarks : The test substance is a solid . Sample was taken fro m 3M lot number 332 . Sample was stored under frozen conditions prior to testing . Purity determined to be 95 .0% by LC/MS, 19F-NMR, and elemental analyses techniques . The impurities were identified as : metals (0 .002%) ; lower chain-length (C6 and C7) perfluorinated sulfonates (4 .68%); NMR impurities (0 .36) . METHO D Method : ASTM E729-9 6 Type : Static renewal GLP : Yes Date completed : Study completed 2007 Species: Chironomus tentan s Supplier : Environmental Consulting and Testing (ECT), Superior, WI Analytical monitoring : PFOA measured at initiation, prior to and after renewal at 48 hours and at test termination (96-hours ) Exposure period : 96-hours Statistical methods : The NOEC determined by visual interpretation of mortality, immobility and observation data . Test organism age : 2nd to 3rd instar larvae (approximately 10 days old) Average wet weight at test initiation: Not provide d Loading : 1 midge per test chamber Pretreatment : Non e Acclimation : Prior to the test, midges were held for 3 days with sand and water from the same sources and at approximately the same temperature as used during the test. Temperatures ranged from 22 .0 to 22 .8C . pH ranged from 8 .1 to 8 .4 . Dissolved Oxygen ranged from 7 .2 to 8 .6 mg/L . Midges were fed a 56 g/L suspension of Tetramin flake food daily during holding . Test conditions : Dilution water : Filtered, aerated well wate r CONTAINS NO CBI /3 7 p. 2 Dilution water chemistry ( during the 4-week perio d immediately preceding the test ) : Specific Conductance : 293 (285-300) Nmhos/cm Hardness : 136 (132-140) mg/L as CaCO3 Alkalinity : 183 (182-184) mg/L as CaCO3 pH : 8 .0 (7 .9-8 .1 ) Stock and test solution preparation : A primary stock solution was prepared at a nominal concentration of 1000 mg active ingredient per liter using a calculated amount of PFOS, and sonicated for 5 minutes and mixed by inversion . After mixing, the primary stock solution was proportionally diluted with dilution water to prepare each test concentration . Each test solution was mixed by inversion . All test solutions were adjusted to 100% active ingredient during preparation, based on test substance purity . All test solutions appeared clear and colorless in the test chambers at test initiation and termination . Solvent : non e Concentrations dosing rate : Static renewal after 48-hours Stability of the test chemical solutions under test conditions : Stable as demonstrated by analytical monitoring . Exposure vessels : 30 mL Nalgene plastic beakers filled with approximately 20 mL of water. Beakers had approximately oneeighth teaspoon of sand on the bottom as substrate . Vessels were covered with plastic wrap. Number of replicates : te n Number of tadpoles per replicate : on e Number of concentrations : Five plus a negative control Photoperiod : 16 hours light and 8 hours dark with a 30-minute transition in simulated natural sunlight from fluorescent bulbs . Feeding schedule : Midges were fed attest initiation on day 0 and attest renewal on day 2 with 4 g/L Tetramin flake foo d Water chemistry during the study : Dissolved oxygen range (0 - 96 hours): 7 .9 - 8 .7 mg/L (negative control exposure) 7 .6 - 8 .7 mg/L (all test substance exposures) pH range (0 - 96 hours ) 8 .2 - 8 .5 (negative control exposure) 7 .9 - 8 .5 (all test substance exposures) Test temperature range (0 - 96 hours) 22 .0 - 22 .6C (negative control exposure) 21 .7 - 23 .0C (all test substance exposures) RESULTS l~ p. 3 Nominal concentrations : Bk control, 63, 125, 250, 500, and 1000 mg/L Measured concentrations : <LOQ, 74, 153, 277, 579, 1090mg/L Element value* : 24-hour LC50 => 1090 mg/L (C .1 . not calculable) 48-hour LC50 => 1090 mg/L ( C.I . not calculable) 72-hour LC50 = > 1090 mg/L (C. I . not calculable) 96-hour LC50 => 1090 mg/L (C .I . not calculable) 96-hour NOEC = 277 mg/L *All element values based on mean measured concentration s Statistical Evaluation of Mortality : Visual interpretation of observations and subsequent recorded data was utilized for assignment of NOEC . Analytical Methodology: Analyses of test solutions were performed at Wildlife International Ltd . The method consisted of dilution of the samples 1 :1, v/v with acetonitrile, followed by secondary dilution using acetonitrile : HPLC-grade bottled water (50 :50, v/v) and analysis by direct injection high performance liquid chromatography with mass spectrometric (LC/MS/MS) detection . The LOQ (limit of quantitation) was 10 mg/L in this study . The measured concentrations of matrix fortifications analyzed concurrently during sample analysis were 97 .0-107% of nominal . Samples collected in exposure vessels at test initiation had measured values from 102 to 106% of nominal . New samples collected at 48 hours had measured concentrations from 1052to 104% of nominal . Old samples collected at 48 hours had measured concentrations ranging from 120 to 141% of nominal . Measured concentrations of PFOS in samples collected at test termination were 107 to 160% of nominal . Summary of analytical chemistry data : Nominal Test Measured Values of New and Old Mean Concentration, Test Solutions Respectively, mg1L(') Measured Percent of mglL Concentration, Nominal m !L Negative Control All < LOQ(2) 63 65 .4 . 74 <LOQ 117 125 130 . 154, 129, 200 153 122 250 259, 302, 259, 289 277 111 500 532, 707, 511, 566 579 116 1000 1020, 1260, 1020, 1070 1090 10 9 (1) Samples are listed in this order : Day 0(new), 48-hours (old), 48-hours (new), 96-hours (old) (2) LOQ = Limit of Quantitation = 10 mg/L active ingredient Biological observations after 96-hours : A 10% mortality rate was observed in the negative control and the 74 mg/L treatment groups . No mo rt alities or signs of toxicity were observed among midges in the 153 and 277 treatment groups during the test . Midges that survived to test termination in the in all treatments appeared normal . Attest termination, 141 p. 4 mo rtality in the 579 and 1090 mg/L treatment group was 30 and 40% , respectively . The only sign of adverse effects observed in the affected midges from the 1090 mg/L treatment group was pale appearance . Cumulative percent mo rtality: Mean Measured Test Conc . , m g!L 25-hours 48-hours 72-hours 96-hours Negative 0 0 0 10 Control 74 0 0 0 10 153 0 0 0 0 277 0 0 0 0 579 20 20 20 30 1090 20 20 30 4 0 Lowest concentration causing 100% mortality : > 1090 mg/L Mortality of controls : 10% CONCLUSIONS The perfluorooctanoic acid, ammonium salt 96-hour LC50 for Chironomus tentans was determined to be > 1090 mg/L . The 96-hour no mortality concentration was 3277mg/L and no observed effects concentration was 277 g/L . Submitter : 3M Environmental Laboratory, Maplewood, Minnesota, 55144 DATA QUALITY Reliability : Klimisch ranking = 1 REFERENCE S This study was conducted at Wildlife International Ltd ., Easton, MD atthe request of 3M . OTHER Last changed : 07/10/07 !q 2-