Document kLRjJDZ7kEm9zRGOrxGYBBLD

FOR DU FONT USE ONLY AR226-2884 Copiei. Co E. I. du Font de Nemours and Company Baskell Laboracory for Toxicology and Industrial Medicine Elkton Road, Newark, Delaware 19711 HASKELL LABORATORY REPORT NO. 494-80 Haskell No. TT383---- ^Ocher Codes/Synonyms' Study Initiated/Completed 4/21/80 - 4/29/80 Material Submitted b; CD&P Dept. Jackson Lab INHALATION MEDIAN LETHAL COSCENTKATIOM (LC50) Introduction; The purpose of this study was to determine the LC50 for Procedure; Groups of 10 ChS-CD rats, 8 weeks old and weighing 235-282 g, were exposed 60 vapor atmospheres of the best material for single 4-hr. periods. Except during exposure, rats were housed in suspended stainless-steel wire mesh cages. Purina Certified Rodent Chow* 1^5002 and water were supplied ad libitum. During exposure, all rats were observed and clinical signs noted. Following exposure, rats were weighed and observed daily (excluding weekends) for a 14-day recovery period. Generation; Vapor atmospheres of the test material were generated by syringe driving the compound through a Spraying Systems nebulizer. The syringe and nebulizer were heated to a temperature of approximately 50C. The aerosol was then -sprayed onto the heated surface of a 3-neck round-boteom flask. Houseline air swept the vapors into a 20 1 glass battery jar* Dry ice was placed on top of dumber to keep temperature < 28 "C. chiraber temperature were monitored throughout each exposure. Oxygen and Analytical; Chamber samples were collected approximately every 30 minutes by drawing ajpownw^.ume of chamber ata.^ sphere through 2 tandem midget impingers contain! 'gg|----|||ps a trapping solvent. These samples were analyzed using a Hewlett ^sfcSw^Ss.el 5710 gas chreaafcog^aph equipped with a flame ionization detector. The column used was a 6' x 1/4" OD glass coil packed with a 20% SE30 on fimpanySanitized. Does not contain TSCA CB 80/100 mesh chromosorb W-HP. The GC was ten) hold at 50C for 2 minutes. Increased at 32 minutes. "-ature programed with an Initial In co 200C, and held there for 2 GC analysis was basedjn the C-8 component. Chamber concentrations are expressed as the equivalent&|^----------concentration (ng/1). Results; Six exposures were conducted* Occasslonally, during exposures, low boiling components caused flash evaporation and high boiling solids caused plugging of the needle. These problems account for the high standard deviation for the exposure concentrations. Concentration g/l 51.2 66.7 70.9 76.9 110 123 S. D. 13.4 41.6 22.7 29.8 14.0 30.0 Fractional Mortality f deaths/ f exposed 0 10 1 10 0 10 7 10 4 10 6 10 Observations; Labored breathing, reduced response Co sound, and salivation were observed during all exposure except one. Mild to severe weight loss 24 hours post-exposure followed by normal height gain was observed in levels ^70.9 mg/1. Gasping, severe weight loss 48 hours post-exposure followed by normaT weight gain was observed at 76.9 ag/1. In levels ^ 110.0 mg/1, severe weight loss 48-72 hours post-exposure followed by normal weight gain was observed. All deaths occurred 24-48 hours post-exposure. Summary: Groups of 8 week-old ChR-CD male rats were exposed to vapors of[^ '^BHEor single 4-hr. periods. The LC5Q** was estimated to be 107 ng/1. HTnety-' "fivepercent confidence intervals could not be calculated due to inconsistency of dose-response. . . Clinical signs observed during exposure included labored breathing, saliva tion, and reduced response to sound. Mild to severe weight loss was observed 24-72 hours post-exposure but normal weight gain was achieved thereafter. 2 j^inpariySanitized. Does not contain TSCA^Rr - * Typical Composition Z ** D. J. Finney, Probit Analysis, 3rd Ed., 1971, Cambridge University Prese. Report by: "r ^7^>f^.^\. 7 t-f.-ff ^ ^ -^^---- ------------ Sat_e_p_hl_e_n_ ------ A D. -- / h - '---- NlTa_s^hr ' ^ Technician Approved by: J^JUL -~--^-- ^^-/. Gerald \ ^ ^ L t--^-----^.r L. Kennedy Chief, Acute Investigations Section SDH:jrg Study Director: Bayanne L. Ferenz .Date Issued; August 21,J.98Q 'Report Ho. 494-80 ^ORipanySanitized. Does not contain TSCA CBf 3 -