Document O7Oj37XgZBv76oMB3BGdMbNv

AR226-2784 FOR DU POUT USE ONLY Copies to Haskell E. I. du Pone de Neaours and Co., Inc. Laboratory for Toxicology and InduBtrial Elkton Road, P. 0. Box 50, Newark, Delaware 19711 Medicine HASKELL LABORATORY REPORT NO. 62-82 Material Tested* Octanolc acid, pentadecaflm-.o-, aiimoniira salt (carbonyl C-labelled) Haakell No. 14,129 Other Codes Study Initiated/Conpleted 6/23/81-9/27/81 Material Subaltted b; Polyner D-11070 [uctB^Deparfent EXCRETION AND DISPOSITION OF 14 C-AMMONIUM PERFLUOROOCTANOATE IN MALE AND FEMALE RATS, MICE, HAMSTERS. AND RABBITS Summary: Sex and species differences in the excretion and disposition of C-labelled ammonium perfluorooctanoate (C-8) were observed in the present study. Substantial sex differences in rats and hamsters were observed in the excretion of C activity following a single oral dose of C-labelled C-8. The female rat and the male hamster excreted over 99 percent -f the original C activity by 120 hours after dosing, conversely the male,rat and the female hamster excreted 39 aiid 60 percent of the original C activity, respectively, by 120 hours poet-dosing. Both sexes of rabbits excreted the C activity as rapidly and completely as the female rat and the male baastere The male and female mice excreted only 21 percent of the original C activity by 120 hours post-dosing. The rapid excretors (female rat, male hamster, and male and female rabbit) contained negligible amounts e-f C in organs,and tissues at sacrifice. The slow excretors exhibited the highest C concentrations in the blood and liver with substantial levels in thr kidneys, lungs and skin. Introduction: The excretion of perfluorooctanoate (C-8) has been shown to differ substantially between male and female rats (1). Female rats excreted over 90 percent of a single dose by 24 hours after dosing. Hale rats excreted only 50 percent of the dose by 4 days after dosing and 15 percent of the dose was still in male rats 32 days after dosing. The purpose of the present study was to make a preliminary examination of the excretion a-sd 1 - Company Sanitized. Does not contain TSCA CB/ raf, 14 disposition of C-labelled C-8 after administration to male rod female ice, hamstera and rabbits. The results should indicate whether sex differences for the excretion and disposition of C-8 occur in specie* other than the rat. Procedures; The C-labelled C-8 was obtained froa 3M Coapany as the eomonium salt. The compound was labelled on the carbonyl position and had a specific activity of 0.5 ^ Ci/ng. The coapound was 70 percent straightchained C-8 and 30 percent branched C-8 isoaers. The radiolabelled compound was readily water soluble, therefore water was used as the dosing vehicle. A male and,a female of each species received a single 10 og/kg oral gavage dose of C-labelled C-8. The rats, nice and hamsters were doused Individually in glass metabolism units ioaediafely after dosing. Bouse vacuum was used Co generate -a 500 uL/ain/airflow through the etaboli-- units. The incoming air was passed initially through successive Drierite- and Aecarite*-filled glass columns to remove water and CO,, respectively. The ajfr leaving the metabolism unit was passed successively through two gas scrubbing bottles, each containing 250 mL (150 mL for mice) 2H HaOH for trapping expired CO,. The 7-N NaOH solutions were changed 12, 24, 48, 72, 96 and 120 hours after dosing. Urine and feces were collected at the saxe tire intervals. The male and female rabbits were individually housed in stainless steel I metabolism cages innediately after dosing. Urine and feces were collected 24, 48, 72, 96, 120, 144 and 168 hours after dosing. Expired CO. was not trapped from the rabbits. Blood vaa withdrawn from the rabbits By cardiac puncture 168 hours after dosing. The rabbits were sacrificed in a C0 chamber following cardiac puncture. The rabbit blood was heparinized and refrigerated in small Nalgene bottles. The rats, mice and hamsters were all sacrificed 120 hours after dosing by chloroform exposure. Blood was drawn by heart puncture upon sacrifice and refrigerated in heparinized tubes. All animals were dissected with the following tissues excised, weighed and frozen: heart, lungs, liver, kidneys, spleen, testes or ovaries, brain, G. I. tract, and muscle, skin and fat samples. The carccsses were then weighed and frozen. Metabolism units (glass and stainless steel) were washed in succession with dilute detergent, water, and acetone. The cage washes were collected in Nalgene bottles and refrigerated. .Urine, CO.-trapping solutions, and cage washes were analyzed directly for C radioactivity using an Intertechnique SL4000 liquid scintillation counter. Blood, feces, tissue, organ and homogenized carcass sauples were analyzed for C content by tissue oxidation using a Packard Model 306 Tissue Oxidizer and liquid scintillation counter. Rabbit carcasses were not analyzed for C content. Cc.rnp?.riy Sanitized. Does not contain TSCA CBE 14 Results: The distribution data of C activity are presented In Table 1. The male rat, female hamster, and both sexee if alee retained substantial amounts of the total administered radioactivity In their tissues at the tiae of sacrifice. In contrast, the female rat, the male hamster and both sexes of rabbit contained only a fraction of a percent of the original dose In their tissues at sacrifice. Orlne was the primary route of .excretion In all species except the mouse. The percent of dose excreted as C-labelled C0 ranged from 1.3 to 5.2 percent In both sexes of rat, mouse and hamster. 14 The total urinary and fecal excretion of C activity me expressed as a cumulative percent of the total dose and plotted against collection time. The profiles for rats and hamsters are presented In Figure 1 and reveal striking sex differences. The male rat and the female hamster exhibited a slow steady Increment for excretion over the 120 hour post-dosing period. The female rat and the mats hamster exhibited a rapid rate for excretion. 3y 48 hours the female rat had excreted almost the entire dose In the urine and feces and the male hamster excreted over 95 percent of the original dose in the same time span. 14 Substantial species differences for excretion of C activity are reflected in Figure 2 which compares the cumulative urine and feces excretion between mice and rabbits. The mice excreted only 11 percent of the total dose in the urine and feces by 120 hours after dosing. By 24 hours the male and the female rabbit had excreted 78 and 86 percent of the dose, respectivelyj in the urine and feces. After 48 hours post-dosing the increment of increase in the rabbit urine and feces was negligible. The profiles presented In Figures 1 and 2 depict the animals as either rapid or slow excretors. The female rat, the male hamster and both sexes of rabbit would be in the former category while the male rat, the female hamster and both sexes of mice occupy the latter category. 14 Tissue distribution of C activity was determined and expressed as y% equivalents of C-labelled C-S per gram (mL) tissue. Tnese data are presented in Table 2 and reflect negligible tissue levels in the rapid excretor3. The slow excretors exhibited t1? highest tissue levels In the liver and blood with measureable levels frasent in all other tissues. Preferential sequestering of C-labelled C-8 in the fat was not observed in any of the animals on study. The lowest limit of accurate detection was 0.1 us equivalent per gram of tissue due to the low specific radioactivity of C-labelled C-8. Conclusion: The data indicated substantial sex or species differences with regard to C-8 excretion and disposition. In general the animals on study can be classified as either slow or rapid excretors of C-8. Mathematical evaluations of the excretion rate were 'not performed because only one animal of each sex and species was used in the study. However, the observed differences were very substantial and indicative of the sex and species differences which can occur for C-8 excretion. Claarly, the excretion rate for C-8 cmnot be predicted for either sex of an unexamined species. The biochemical mechaniso(s) for thi; observed sex and species differences In elimination and disposition of C-S remain to be elucidated. ,^,Ooosn,.c.n^TSCACBI Compaq Reference: 1. Dow Chemical Company (personal communication). * Synonyms: o Ammonium perfloorooctanoate ---- o C-8 ^^ tP^& CAS Registry NP^: fU^^9\ Report by: fU^Jli^ jk-t.^AL^t^ftU^JiS^. ^ [ Stephen G. HBuunnddleleyy^^'' ' Research BBiioocchheea^tBMl Approved by; SGH:tac:WP:l.l4 Date Issued: November 12>^1982 1'Haskell Lab. Report Ho. 62-82 ^I^J^^) Airai Sarrif Section Supervisor Biochemical Toxicology - 4 - ^con^50^ - Sanded. 00-; COWP^-""1' TABLE 1 Distribution of ^C Activity Following ^-Labelled C-8 Administration to Both Sexes of Bats, Mice, Hamsters and Rabbits Percent of Original Dose (a) Sample Urine Rat Male Female 25.6 73.9 House Male Female 3.4 6.7 Hamster Male Female 90.3 45.3 Rabbit Male Female 76.8 87.9 Feces 9.2 27.8 8.3 5.4 8.2 9.3 4.2 4.6 Tissues 59.6 0.6 73.6 50.0 0.7 26.5 <0.1 0.3 CO^ 3.5 1.5 5.2 4. 1.3 2.9 (b) Cage Wash 0.6 0.8 4.9 4.9 0.6 2.1 0.5 4.8 14 (a) Each animal received a single 10 mg/kg oral gavage dose of C-labelled C-8. The rats, mice, and hamsters were held 120 hours and the rabbits 169 hours after dosing. (b) Expired CO. was not collected for the rabbits. - 5 - Company Sanitized. Does not contain TSCACBl TABLE 2 , 14, Tissue Distribution of C-Radioactivity Proa Both Sexes of Rats, Mice, Haastere and Rabbits Dosed With C-Labelled C-8 ' fig Equivalent per g(oL) Wet Weight (b) Rat Sample Male Female Blood 23.5 <0.1 Liver 40.0 <0.1 Kidneys 24.0 <0.1 Lungs &.7 <0.1 Heart 6.4 <0.1 Skin 4.8 <0.1 Testes 3.2 - Muscle 1.9 <0.1 Fat 1.7 <0.1 Brain 0.6 <0.1 Hou se Male Female 13.8 10.1 43.2 45.3 2.9* 2.2* 1.4* 1.3* 1.2* 0.6* 3.5 3.2 0.9* - 1.1 0.5 1.6 1.3 0.2* 0.8* Haaster Male Female 0.1 8.8 0.3 7.3 0.2 7.1 <0.1 3.8 <0.1 2.9 <0.1 3.4 <0.1 - <0.1 O.S <0.1 1.5 <0.1 0.3 Ra bbit Male Feaale <0.1 0.1 0.1 1.5 0.1 0.4 <0.1 0.1 <0.1 <0.1 <0.1 <0.1 <0.1 - <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 (a) The rabbits were sacrificed 168 hours after dosing, all other aniaals were sacrificed 120 hours after dosing. of (b) The _ug equivalent calculations were,based upon the specific activity C-labelled C-8 which was 1.1 x 10 DPM/Bp. The jig equivalent per g vet Height could not accurately be determine'' below 0.1_ug/g. * Represents the jig equivalents for thf entire organ. - 6 - ^s--------------------"81 FIGURE 1 Cumulative Urinary and Fecal Excretion of ^C Radioactivity in Rats and Hamsters Q 0 (5 w 0 Q &< m o & ro OS & 0 W NoiiaHDxa iMaMad aALivinymo - 7 - Company Sanitized. Doss noi cor'i?."' TSCA C.'3{ FIGURE 2 Cumulative Urinary and Fecal Excretion of ^C Radioactivity in Mice and Rabbits 11 i j i 11 11111 11111 0 0 j l 0 ^ 0 0 - 2 " Z 0 L E- ^^ ^^^^ M ^ - -i U X M ^ <; U M - fc Q 2 ^ M ^ t fk^^^^^ ^ - : ~ -! r ., \ ' \ \ ' \ 0 0 0 < 0 - -o 9 0 ^r H CU . 1 S53 ' - -o I 0 P 0 1 B T JO'- ' L^ CO 1 J 2 1 - S K t 1 TM ;=> - 1 -lo 0 B 0 1 - CO 1 ^ I ~ 0 I 0 1 -:0' l^-o \ o \- cu 0 0^0 0 0 0 JJ0 -U- 0 0 0 0 -Li0. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O! CD r^ CD !D '<? 03 nj NoiianDxa iMgoHad aAii^npino sann.z.a.oo^.""-31"""'"' Company