Tetraethylammonium heptadecafluorooctanesulphonate

Toxicity to reproduction

Administrative data

Endpoint:

two-generation reproductive toxicity

Remarks:

based on test type (migrated information)

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: secondary literature

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Two-generation reproduction and cross-foster studies of perfluorooctanesulfonate (PFOS) in rats

Author:

Luebker DJ, Case MT, York RG, Moore JA, Hansen KJ, Butenhoff JL

Year:

2005

Bibliographic source:

Toxicology 215, 126-148

Reference 2

Reference Type:

secondary source

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 416 (Two-Generation Reproduction Toxicity Study)

Principles of method if other than guideline:

One hundred seventy-five male and female Crl:CD(DBR VAF/Plus(D (Sprague- Dawley) rats were assigned to five dosage groups (Groups I through V),35 rats per sex per dosage group. The rats were administered the test article PFOS, or the vehicle, 0.5% Tween 80, orally (via gavage). The dosages were 0 (Vehicle), 0.1, 0.4, 1.6and 3.2mg/kg/day. The male rats were dosed once daily beginning 42 days before cohabitation and continuing through the day before sacrifice. The female rats were dosed once daily beginning 42 days before cohabitation and continuing through DG9 (rats assigned toCaesarean sectioning) DG 24 (rats assigned to natural delivery that did not deliver a litter), or DL 20 (rats that did deliver a litter). The dosage volume was 5 ml/kg.
Only the 0.1 and 0.4 mg/kg/day dosage groups were continued into the second generation because of the excessive toxicity seen in the 1.6 and 3.2mg/kg/day Fl generation pups.
There were 150 male and female Fl generation rats in the three dosage groups (Groups I through III) 25 rats per sex per dosage group. Fl generation male and female rats were given appropriate dosages of the test article orally (gavage) beginning on DL 22 and continuing through the day before sacrifice.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Potassium heptadecafluorooctane-1-sulphonate

EC Number:

220-527-1

EC Name:

Potassium heptadecafluorooctane-1-sulphonate

Cas Number:

2795-39-3

IUPAC Name:

potassium 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluorooctane-1-sulfonate

Details on test material:

Identity: Potassium Perflurooctylsulfonate, CAS No. 2795-39-3.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 0.5% Tween 80 in water

Details on mating procedure:

Fo GenerationRats/FlGeneration/litters
Fo generation rats were individually housed in stainless steel wire-bottomed cages except during the cohabitation and post partum periods. During
cohabitation, each pair of rats was housed in the male rat's cage. Beginning no later than DG 20, Fo generationfemale rats assigned to natural delivery were individually housed in nesting boxes. Each dam and delivered lifte wrere housed ina common nesting box duringthe postpartum period.
Fl Generation Rats/F2 Generation Litters
After weaning,the Fl generation rats were individually housed before cohabitation, housed in pairs( one male rat per female rat)during cohabitation,
and individually housed after cohabitation. The same type of caging was used as described for the Fo generation rats.Beginning no latert han DG 20,
Fl generation female rats were individually housed in nesting boxes. Each dam and delivered litter were housed ina common nesting box during the postpartum period.

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

The Fo generation male rats were given appropriate dosages of the test article once daily beginning 42 days before cohabitation (which continued for a maximum of 14 days) and continuing through the day before sacrifice.
Fl generation male and female rats were given appropriate dosages of the test article orally(gavage),beginningon day 1 postweaning (DL 22)8and continuing
throughtheday beforesacrifice. F2 generationpups were notdirectly giventhe
testarticleb,ut may have been possiblyexposed tothe testarticldeuring
gestation(inuteroexposure)or viamaternalmilkduringthe lactationperiod.

Frequency of treatment:

daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 0.1, 0.4, 1.6, and 3.2 mg/kg/day
Basis:
nominal conc.

No. of animals per sex per dose:

F0: 35 animals per dosage group
F1: 25 animals per dosage group

Control animals:

yes, concurrent vehicle

Results and discussion

Results: P0 (first parental generation)

Effect levels (P0)

Dose descriptor:

NOAEL

Effect level:

0.1 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Results: F1 generation

Effect levels (F1)

1

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

0.1 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

female

Basis for effect level:

other: F1 generation parenteral

2

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

0.4 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: F1 generation offspring

Results: F2 generation

Effect levels (F2)

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

0.1 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: F2 generation offspring

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

In the F0 generation male rats, there were no treatment-related clinical signs of toxicity, no mortality, and no effects on mating or on any of the fertility parameters evaluated in any dose group tested. Reported effects included reductions in both body weight gains and in absolute and relative food consumption at the 1.6 and 3.2 mg/kg/day dose groups during the pre-mating period. Following mating, food consumption was significantly reduced in the 0.4. and 1.6 mg/kg/day dose groups. Terminal body weights were also significantly reduced in the 1.6 and 3.2 mg/kg/day dose groups. Significant reductions in the absolute weights of the seminal vesicles (with fluid) and the prostate were observed in F0 males at 3.2 mg/kg/day; no other organ weight changes were reported. A significant increase in the number of males with brown liver at 3.2 mg/kg/day dose group was also reported.

In the F0 generation female rats, no deaths were reported at any dose level. In dams sacrificed on GD 10 for Caesarean-sectioning, there did not appear to be any effects on estrous cycling, mating and fertility parameters, the numbers of corpora lutea and implantations, or in the number of viable or non-viable embryos. The only findings reported in the F0 dams occurred in the 0.4, 1.6, and 3.2 mg/kg/day dose groups and included localized alopecia during pre-mating, gestation, and lactation; and reductions in body

weight and body weight gain and food consumption values observed during the pre-mating period and continuing throughout gestation and lactation.

Reversible delays in reflex and physical development were observed in the F1 generation offspring. The ability to surface right was significantly delayed in the 1.6 and 3.2 mg/kg/day dose groups on LDs 3-10 (delays in the 3.2 mg/kg/day dose group were observed on LD 1, after which there were no surviving pups remaining for further observation). By the end of the observation period, however, all surviving pups in the 1.6 mg/kg/day dose group had the ability to surface right. There were no delays observed in the ability to surface right in dose groups < 0.4 mg/kg/day. Similar responses were seen for pinna unfolding and eye opening. Although there were transient delays seen with these signs of physical development across all dose groups, by the end of the observation period responses in pups were similar to controls. The time of development of the acoustic startle reflex and the ability to air right were both significantly reduced in the 1.6 mg/kg/day dose group. No effects on these reflexes were observed in the low dose group of 0.1

mg/kg/day and only a transient delay (on LD 16 only) in the ability to air right was seen in the 0.4 mg/kg/day group. At the end of lactation (LD 21), all live pups in all dose groups (0, 0.1, 0.4, and 1.6 mg/kg/day) had pupil constriction response.

The most significant finding reported in the offspring was that of reduced pup viability at the two highest dose groups. The reductions in pup viability began to appear on LD 4 postculling in the 1.6 mg/kg/day dose group, with over 26% of the pups found dead between LD 2-4. In the 3.2 mg/kg/day dose group 45% of the pups were found dead on LD1; no pups survived beyond LD 1. Statistically significant increases in the number of dams with stillborn pups were also observed at 3.2 mg/kg/day. As a result, the viability index was greatly reduced in these dose groups (0% at 3.2 mg/kg/day and 66% at 1.6 mg/kg/day). The lactation index was also significantly reduced (94.6%) in the 1.6 dose group. In addition, gestation length was significantly reduced in the high-dose group and there also was a significant reduction in the number of implantation sites followed by a concomitant reduction in litter size. Statistically significant reductions in pup body weights were also observed at the two highest dose groups. Other adverse signs in the 3.2 mg/kg/day dose level associated with reductions in pup viability and maternal care included litters with pups that were not nursing or who had no evidence of milk in the stomach, as well as maternal cannibalization of pups that were stillborn or found dead.

Since F1 generation pup viability was significantly reduced in the 1.6 and 3.2 mg/kg/day dose groups, only the 0.1 and 0.4 mg/kg/day dose groups were carried into the second generation.

Clinical observations in the F1 generation male rats appeared unremarkable. No treatment-related deaths were reported and no statistically significant differences were reported for any of the following parameters: body weights/body weight gains, average day of preputial separation; values for learning, short-term retention, long-term retention or response inhibition as evaluated by performance in a passive avoidance or watermaze performance paradigm; mating or fertility parameters; necroscopic examinations; absolute or

relative weights for the right or left testis, seminal vesicles, right epididymis, or prostate; and terminal body weights. The only reported effects were significant reductions in absolute food consumption on postweaning days 1-8 occurring at the 0.1 and 0.4 mg/kg/day dose levels.

Clinical observations for the F1 generation females were likewise unremarkable. Observations at the 0.4 mg/kg/day dose group included, reductions in body weights on day 1 postweaning, significant losses in body weight on LDs 1-4, and significant reductions in food consumption on days 1-8 postweaning and during lactation. There were no statistically significant differences reported for any of the following parameters: values for learning, short-term retention, long-term retention or response inhibition as evaluated by performance in a passive avoidance or water maze performance paradigm; mating and fertility parameters; gestation index; pregnancy rates; and necroscopic examinations.

Evidence of treatment-related effects in the F2 generation pups consisted of reductions in mean pup body weights (on a per litter basis) observed at 0.1 mg/kg/day on LD 4 and 7. Body weights were comparable to control levels by LD 14. At 0.4 mg/kg/day, statistically significant reductions in mean pup body weights were observed on LDs 7 and 14. Mean body weights on LD21 continued to remain lower than controls, although the difference was not statistically significant (46.5 g in 0.4 mg/kg/day dose group vs. 50 g in controls). Clinical and necroscopic observations of the F2 generation pups were unremarkable. No other

toxicologically significant effects were reported.

Applicant's summary and conclusion

Executive summary:

One hundred seventy-five male and female Crl:CD(DBR VAF/Plus(D (Sprague- Dawley) rats were assigned to five dosage groups (Groups I through V),35 rats per sex per dosage group. The rats were administered the test article PFOS, or the vehicle, 0.5% Tween 80, orally (via gavage). The dosages were 0 (Vehicle), 0.1, 0.4, 1.6 and 3.2 mg/kg/day. The male rats were dosed once daily beginning 42 days before cohabitation and continuing through the day before sacrifice. The female rats were dosed once daily beginning 42 days before cohabitation and continuing through DG9 (rats assigned to Caesarean sectioning) DG 24 (rats assigned to natural delivery that did not deliver a litter), or DL 20 (rats that did deliver a litter). The dosage volume was 5 ml/kg.

Only the 0.1 and 0.4 mg/kg/day dosage groups were continued into the second generation because of the excessive toxicity seen in the 1.6 and 3.2mg/kg/day Fl generation pups.

There were 150 male and female Fl generation rats in the three dosage groups (Groups I through III) 25 rats per sex per dosage group. Fl generation male and female rats were given appropriate dosages of the test article orally (gavage) beginning on DL 22 and continuing through the day before sacrifice.

Under the conditions of the study, the NOAEL and LOAEL for both the F0 generation male and female parents are 0.1 mg/kg/day and 0.4 mg/kg/day, respectively, based on reductions in body weight gain and food consumption. The NOAEL for the F1 generation parental males could not be established since treatment-related reductions in absolute food consumption values were reported at the lowest dose tested, 0.1 mg/kg/day. The NOAEL and LOAEL for the F1 generation parental females are 0.1 mg/kg/day and 0.4 mg/kg/day, respectively, based on significant reductions in body weights and food consumption. The NOAEL and LOAEL for the F1 generation offspring are 0.4 mg/kg/day and 1.6 mg/kg/day, respectively, based on significant reductions in the number of implantation sites, litter size, pup viability, pup body weight and survival. The NOAEL and LOAEL for the F2 generation offspring are 0.1 mg/kg/day and 0.4 mg/kg/day, respectively, based on significant reductions in mean pup body weight.