Document 99Jd8GG6MzXnk8QrN9VvKZN55

AR226-3387 A 90-Day Gavage Study with One-Generation Reproduction Evaluations in Rats with a Fluoroalkylethanol Mixture E. Mvlchreest, J.C. Stadler, G.T. Makovec, N.E. Everds, and G.S. Ladies The DuPont Company, Haskell Laboratory for Health and Environmental Sciences, Newark, Delaware, USA , B M Abstract The objective of this study was to evaluate the subcltronic and reproductive toxicityo f a fluoroalkylethanol mixture which is employed as an intermediate in tlte production ofother fluoroorganic compounds utilized as protectants and surfactants. Test material was administered by gavage at dosages o f0,25,100, or 250 mg/kg/day. No test substance-related mortality or neurotoxicity occurred in the study. Body weights and/or nutritional parameters were significantly reduced at 100 and 250 mg/kg/day but similar to control after recovery. Broken and absent teeth were observed at 2S0 mg/kg/day. Microscopic tooth lesions (ameloblast degeneration/disorganization) occurred at 100 and 250 mg/kg/day and persisted after recovery. Plasma and urine fluoride levels were elevated in a dose-dependent manner. Decreased red cell mass parameters occurred at 250 mg/kg/day and persisted after 36 days of recovery. The 100 and 250 mg/kg/day groups had increased (p < 0.05) liver weights which persisted ia the high dose after recovery and correlated with microscopic hepatocellular hypertrophy in males and females<250 mg/kg/day subchronic animals only). Hepatic 15oxidation was increased in a dose-dependent manner and persisted after recovery at 250 mg/kg/day. Increased kidney weightsoccuned at 25 (females only), 100 and 250 mg/kg/day wliich persisted in (he liigh dose after recovery and correlated with microscopic tubular hypertrophy (males only). Thyroid follicular hypertrophy was present at 100 and 250 mg/kg/day but was not present after recovery. The test material contains 256 residual iodides. Litter size at birth and pup weights during lactation were reduced at > 100 mg/kg/day. No other reproductive parameter was affected. There were no adverse effects observed foreldter subchronic or reproductive toxicity in animals dosed with 25 mg/kg/day. A wide margin of safety exists between potential human exposure levels and the doses which result in adverseeffects. Study Design i Liver Effects Increased liver weiglus at all dose levels and ccntrilobuiar hepatocellular hypertrophy at 2 100 mg/kg/day (males), and 250 mg/kg/day(females). Increased liver weight (males and females) and hepatocellularhypertrophy (males) persisted after one and three month recovery period at 250 mg/kg/day. Increased rate of hepatic 0-oxidation in males and females at 2 100 mg/kg/day, which persisted after the one- and three-month recovery period at 250 mg/kg/day. Tooth Effects Absent or broken teeth observed clinically at 250 mg/kg/day Degeneration/disorganization ofenamel organ ameloblast cells (males and females) at 2 100 mg/kg/day. Ameloblastic degeneration/disorganization persisted with decreased incidence and severity at 2S0 mg/kg/day (males and females) after a one- and three-month recovery period, and at 100mg/kg/day (males) after a three-month recovery period. m r t p Numbers and Survival: F l Generation Dose (ing/kg/day) 0 25 100 250 N 13 17 14 13 Bom Bom Alive Day 4 Preculling Day 4 Postculling Day 7 Day 14 Day 21 Mean Number of Pups/Littcr 14.7 13.4 12.4 12.5* 14.6 13.2 11.3 12.1* 14.6 12.9 10.0* 11.8* 8.0 7.6 6.3 7.5 8.0 7.6 6.3 7.4 8.0 7.6 6.3 7.4 8.0 7.6 6.3 7.4 Sex Ratio (males) 0.S9 0.50 0.50 0.56 Gestation Index* 100.0 Mean % Bom Alive 99.5 0-4 Day Viability 100.0 Lactation Index* 100.0 Litter Survival' 100.0 Survival (%) 100.0 92.9 99.2 88.4 97.6 90.6 100.0 100.0 100.0 92.3 100.0 92.4 97.3 92.3 92.3 |Introduction The test substance is an intermediate in the production o f other fluorotelomer-based products that are used as protectants and surfactants. The test material was administered by gavage, the route selected as the most efficient way to deliver an accurate dosage. Dosage levels for (his study were selected based on the toxicity and pharmacokinetic analysis of plasma fluorine concentrations from a range-finding study. Toxicity (Lc,, body weight effects or clinical observations) was not observed in rats exposed to 200 mg/kg/day for 35 days, however, plasma fluorine levels approached levels previously seen when mortality occurred. The high-dose level of 250 mg/kg/day was expected to produce toxicity without excessive mortality. The low dose of 25 mg/kg/day was expected to be the no-observedeffect level, while tlse 100 mg/kg/day dose was expected to induce minimal or no toxicity. Perfluoroalkylethanol Stu d y Material C om position \ Blood Effects Plasma Fluoride Mildly increased at 2 100 mg/kg/day (males and females) No increase afterone-month recovery Urine Fluoride Increased at 2 25 mg/kg/day (males and females) Increased at 2 100 mg/kg/day (males) and at 250 mg/kg/day (females) after one- and three-month recovery 94.67% RCFjCFjJ.CHjCHjOH 2.01% F(CF2CFJ),,CH2CH2I 5150 ppm Total Elemetal Iodine [ 1 j 12 ppm free Iodide [ I-] ; Objective Evaluate the potential subchronic and reproductive toxicityo f a fluorotelomer alcohol (a-k.a. perfluoroalkylethanol) mixture in male and female rats. Recovery evaluations w included to investigate the reversibility of any observed toxicological effects. Minimally decreased red cell mass parameters, along with correlative changes in other hematology parameters and red cell morphology at 250 mg/kg/day (males and females). After one month of recovery, mean red cell moss o f female rats was similar to control, although some changes were still present in other hematological parameters. Male rats still had decreased redcell mass effects, and associated alterations in otlter hematological parameters. No toxicoiogically significant clmnges in clinical chemistry parameters observed at any dose Thyroid Effects Increased thyroid hypertrophy at 2 100 ing/kg/day (males) and 250 mg/kg/day (females). No thyroid hypenxophy after one month recovery. I Reproduction Evaluation There were no compound.related effects on the following parameters: Body weights, body weight gains, food consumption and food efficiency in P, female rats during gestation and lactation Clinicalobservations in P, and F, male and female rats Estrous cycle and sperm parameters in P, rats Mating, fertility, gestation length and number of uterine implantation sites in P, female rats Body weight gain, preputial separation and vaginal opening in F, rats There were contnound-related effects on tile following parameters: Body weiglus in P, male rats <89-91% of control) at 250 mg/kg/day. In the absence o f any concomitant reduction in body weight gain this was not considered toxicoiogically significant. Numberof pups bom, bom alive and alive on day 4 at 2 100 mg/kg/day (see table). Implantation efficiency (# pups bom/implants) in P, female rats at 2 100 mg/kg/day (83.4 and 84.5% respectively compared to 96.6% in the control group) and reflects the reduction In the number of pups bom. ' Pup weights during lactation at 250 mg/kg/day (see table). Post-weaning body weights in F, male and female rats. In the absence of any concomitant reduction in body weight gain, this was considered due to the lower body weight at weaning and was not considered toxicoiogically significant. W P u p Weights: F, Generation Dose (mg/kg/day) 0 25 100 250 N 13 17 13 13 DayO Day 4 Precuiling Day 4 Postculling Day 7 Day 14 Day 21 69 (0.7)* 11.3(1.5) 11.4(1.6) 18.3 (1.9) 37.9 (3.4) 60.9 (69) Mean Pud Weiehts (crams) 6.7 (0.6) 6.8 (0.7)" 11.4 (1.6) 11.9 (1.8) 11.4 (1.7) 11.9 (1.9) 18.0 (2.2) 18.3 (2.4) 37.0 (3.0) 36.1 (3.2) 60.3 (5.5) 58.3 (4.3) 6.4 (0.6) 10.1 (1.7)* 15.5(2.1)* 29.5 (3.4)* 4S.4 (7.7)* HHB Discussion The increases in plasma and urine fluoride were considered to be secondary to the administration o f a mixture containing fiuorinated compounds and/or free fluoride. The presence of fluoride in urine three months after exposure suggests that fluoridecontaining compounds are slowly being released from tissue sites. The effects seen in teeth are consistent with elevated levels o f fluoride. Liver effects that included increases in liver weights, peroxisome proliferation as indicated by elevated 0-oxidation, and liver hypertrophy are also related to the fiuorinated test material. Thyroid effects may have been due to the presence of iodine in the test materiaL Reproductive toxicity occurred at the same dose levels as the subchronic toxicity indicating that protection from subchronic toxicity would likely also protect from the reproductive effects. I Conclusions NOEL for Subchronic Toxidty: The no-observed -effect level (NOEL) for males and females was 25 mg/kg/day based oa adverse decrements in body weigftt parameters and food efficiency (males only), increased hepatic peroxisomal 0-oxidation, and the degeneration and/or disorganization of enamel organ ameloblast celts at 100 mg/kg/day. NOEL for Reproductive Toxicity: The NOEL for the reproductive evaluations was 25 mg/kg/day based on decreases in the numbero f pups bom, bone alive and the number of pups alive on day 4 of lactation at 100 mg/kg/day.