Docusate sodium

Toxicity to reproduction

Administrative data

Endpoint:

three-generation reproductive toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1984-10-04 To 1985-12-30

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study has been extensively conducted, but has not all parameters as requested in the guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

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:

No sperm investigation, estrus cycle, organ weights, histopathology.

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Docusate sodium

EC Number:

209-406-4

EC Name:

Docusate sodium

Cas Number:

577-11-7

Molecular formula:

C20H38O7S.Na

IUPAC Name:

sodium 1,4-bis[(2-ethylhexyl)oxy]-1,4-dioxobutane-2-sulfonate

Details on test material:

- Name of test material (as cited in study report): Aerosol® OT-100, Sodium Dioctyl Sulfosuccinate
- Physical state: white, waxy solid
- Analytical purity: 99.4%

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material:4DSS02 and 5DSS02
The first batch (4DSS02)was used through October 28, 1985. The second batch (5DSS02) was used from October 29, 1985 until completion of the study.


STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Stability under test conditions: Stable for at least 28 days at room temperature.

Test animals

Species:

rat

Strain:

other: Crl: CD(SD) BR purchased as weanlings

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Wilmington, Massachusetts (Portage, Michigan facility)
- Age at study initiation: P=F0 approximately 7 wks; F1 in utero
- Fasting period before study: No
- Housing: individually in suspended, stainless steel, screen bottom cages, held on racks, with deotized animal cage boards (DACB, Shepherd Specialty Papers, Inc., Kalamazoo, Michigan)lining the urine- and feces-collecting pans.
During mating periods, double-sized stainless steel cages were used to house one male and one female rat. Cage boards were changed at least twice weekly and animals were transferred to clean cages at least biweekly except during the mating period. Pregnant rats (during the last week of gestation) and rats with young, as well as females that did not exhibit evidence of positive mating, were individually housed in plastic cages fitted with water bottles filled with tap water. A bedding material consisting of heat-treated hardwood chips (Beta-Chip, Northeastern Products Corporation, Warrensburg, New York) covered the bottom of the cages, and was changed at least once weekly. Variations from these procedures are documented in the raw data.
- Diet: ad libitum from glass containers that limit spillage and contamination and allow easy inspection of the amount and condition of the feed. The basal diet for this study was ground Purina Certified Rodent Chow #5002. A record of all lot numbers is included in the raw data. This diet has and the minimum or maximum concentrations of these materials are specified.
- Water : partially demineralized by reverse osmosis and sterilized by ultraviolet light, ad libitum from an automatic watering system (Systems Engineering, Palo Alto, California), except during the last week of gestation and during lactation when tap water was provided in water bottles to animals in plastic cages. Hazleton Laboratories America, Inc. (HLA) analyzed the tap water and water from the automatic system quarterly for total dissolved solids, conductivity, heavy metals, organophosphates, chlorinated hydrocarbons, microbiological content and selected elements. Results of these analyses were within normal limits and are on file at HLA.
- Acclimation period: at least 4 weeks

ENVIRONMENTAL CONDITIONS
- Temperature : 72°F ± 3° (20,5 - 23,8 °C)
- Humidity (%): 50% ± 20%
- Air changes (per hr): at least 10 changes an hour, filtered 100% outside air

Administration / exposure

Route of administration:

oral: feed

Vehicle:

acetone

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: Approximately 1,500 g of the weighed rodent chow was transferred to a Hobart N50. DSS was added to a measured amount of acetone and the admixed with the basal diet in the Hobart N50 for 5 minutes. This premix was then added to the rodent chow in the Hobart H600T mixer and mixed for 15 minutes to achieve the proper concentration in the feed.
Each dose level for the study was prepared independently, first the low dose and then progressively higher doses.

DIET PREPARATION
- Rate of preparation of diet (frequency): weekly
- Mixing appropriate amounts with (Type of food): Certified Purina Rodent Chow® #5002
- Storage temperature of food: mixed feed was stored refrigerated in air-tight polyethylene buckets.

VEHICLE
- Justification for use and choice of vehicle (if other than water): acetone

Details on mating procedure:

- Impregnation procedure: cohoused
- M/F ratio per cage: 1/1
- Length of cohabitation: maximum 21 days
- Vaginal smears were taken daily to demonstrate mating.
- After 21 days of unsuccessful pairing females were placed in a plastic cage
- Further matings after two unsuccessful attempts: not applicable
- Proof of pregnancy: vaginal plug / sperm in vaginal smear referred to as day 0 of gestation

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Analyses of the prepared diets were done prospectively (i.e., before feeding to the animals). This method is based on the hydrolysis of DSS to 2-ethyl- hexanol which is then quantitated by gas-liquid chromatography. Analyses were performed weekly for the first 4 weeks, weekly during the 2-week premating phase for F0 females, twice during breeding for F1 litters, twice during F1 gestation, twice during F1 lactation, and monthly thereafter.
Because the analytical method for DSS is based on measuring a possible degradation product (2-ethyl hexanol), it was necessary to determine if measurable quantities of 2-ethyl hexanol were present in nonhydrolyzed diet samples. To do this, several sets of diets were analyzed for DSS and 2-ethyl hexanol after 8 days at ambient conditions and/or after being stored frozen for 1 to 14 days.

Duration of treatment / exposure:

F0 generation animals received the test material at the appropriate dose levels in the diet continuously, from approximately 7 weeks of age (October 4, 1984 for males; November 29, 1984 for females), throughout mating, gestation, and lactation and until they were necropsied on March 4, 5, and 6, 1985.
F1 and F2 generation animals were exposed to the test material in utero, while nursing, continuously from when they weaned to test diets , throughout mating, gestation, and lactation, and until they were necropsied on July 22, 23, and 24, 1985 (F1 animals) and on December 26 and 30, 1985 (F2 animals).

Frequency of treatment:

Daily

Details on study schedule:

- F1 parental animals not mated until test diets had been fed to the animals for at least 10 weeks postweaning for all litters. Pups were allowed to nurse for 21 days before weaning. At weaning, F1 and F2 offspring were group-housed by sex by litter during the interim period elapsing between weaning of the first litter and weaning of the last litter prior to random selection of males and females for the 10-week pre-mating treatment period. All offspring were weaned directly onto their parents’ respective control or DSS diets. Breeding of the F0 generation for F1 litters was initiated on December 13, 1984 after males and females had received test material for 10 and 2 weeks, respectively. Breeding of the F1 generation for F2 litters was initiated on April 25, 1985 after test diets had been fed to the animals for at least 10 weeks postweaning for all litters. Breeding of the F2 generation for F3 litters was initiated on September 12, 1985 after the animals had received test material for at least 10 weeks postweaning for all litters.
- Selection of parents from F1 generation when pups were 21 days of age.
Four days after birth (Day 4 of lactation), the number and sex of pups, individual pup weights, and the presence of milk in the abdomen (for F2 and F3 litters) were recorded. Pups were culled from the litters at random to achieve a maximum litter size of 10, with 5 males and 5 females/litter if possible.
Pups were allowed to nurse for 21 days before weaning. At weaning, F1 and F2 offspring were group-housed by sex by litter during the interim period elapsing between weaning of the first litter and weaning of the last litter prior to random selection of males and females for the 10-week pre-mating treatment period.
- Age at mating of the mated animals in the study: minimum 13 weeks (21 days weaning and 10 weeks pre-mating)

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

0 other: % nominal in diet

Doses / concentrations 2

Dose / conc.:

0.1 other: % nominal in diet

Doses / concentrations 3

Dose / conc.:

0.5 other: % nominal in diet

Doses / concentrations 4

Dose / conc.:

1 other: % nominal in diet

No. of animals per sex per dose:

Dosing (F0, F1 and F2): 30/sex/group (0%, 0.1%, 0.5%, 1.0%)

Control animals:

yes

Details on study design:

- Dose/Route selection rationale: The oral route by diet was based upon human oral exposure.
- Rationale for animal assignment: The selection of F1 pups from each litter was started 4 days after birth (Day 4 of lactation). Pups were culled from the litters at random to achieve a maximum litter size of 10, with 5 males and 5 females/litter if possible.
Pups were allowed to nurse for 21 days before weaning. At weaning, F1 and F2 offspring were group-housed by sex by litter during the interim period elapsing between weaning of the first litter and weaning of the last litter prior to random selection of males and females for the 10-week pre-mating treatment period.

Positive control:

No

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: No

BODY WEIGHT: Yes
- Time schedule for examinations:
males: weekly
females: weekly during pre-mating phases; on Days 0, 7, 14,and 20 of gestation; and on Days 0, 7, 14, and 21 of lactation

FOOD CONSUMPTION AND COMPOUND INTAKE: Yes
- Food consumption for each animal determined (g ): Yes
- Compound intake, (mg/kg/day): Yes


POST-MORTEM EXAMINATIONS: Yes
- Sacrifice of all adults (F0, F1 and F2): after litters have been weaned
- Organs examined: colon, duodenum, epididymides, (gross lesions), ileum, jejunum, kidneys, liver, mammary gland with skin, ovaries, prostate, seminal vesicles, stomach, testes, uterus, vagina.

OTHER:
- One male and one female F1 pup were selected at random from each litter previously weaned onto their respective diets and designated to be used for a possible recovery phase.

Oestrous cyclicity (parental animals):

Not examined.

Sperm parameters (parental animals):

No sperm investigation performed.

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes
- If yes, maximum of 10 pups/litter (5/sex/litter as nearly as possible); excess pups were killed and discarded.

PARAMETERS EXAMINED
The following parameters were examined in F1 / F2 / F3 offspring:
number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies, weight gain, physical or behavioural abnormalities

GROSS EXAMINATION OF DEAD PUPS:
yes, for external and internal abnormalities; possible cause of death was not determined for pups born or found dead.

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals after litters had been weaned
- Maternal animals: All surviving animals after litters had been weaned

GROSS NECROPSY
- Gross necropsy consisted of external and internal examinations including the cervical, thoracic, and abdominal viscera.

HISTOPATHOLOGY / ORGAN WEIGHTS
Microscopic examination of the collected tissues was not required.

Postmortem examinations (offspring):

SACRIFICE
- The F1 and F2 offspring not selected as parental animals and 20 weanlings/sex/group of the F3 litters were sacrificed at 5 days of age (Day 4 of lactation).

GROSS NECROPSY
- Gross necropsy consisted of external and internal examinations including the cervical, thoracic, and abdominal viscera.

Statistics:

Differences between treated groups and the control group were considered statistically significant at p≤0.05 and are indicated with an asterisk(*).
Data for adult animals were analyzed by sex. Body weight; body weight gain; food consumption; reproduction indices; precoital interval; length of gestation; pup viability; body weights, body weight gains, and sex ratios; and litter size (alive and dead by sex) were analyzed separately using one-way nalyzes of variance (ANOVA) with transformation when necessary (log10, square, square root, reciprocal, arcsine rank) to attain variance homogeneity. If the ANOVA was significant, Dunnett’s test was used to compare each treated group with the control. When no transformation could establish variance homogeneity (as indicated by Levene’s test at p<0.01), all data were also examined by nonparametric techniques. These statistics included the Kruskal-Wallis H-test analysis of variance and, if this test was significant, the Nemenyi (F0 and F1 generations) or the Nemeneyi-Kruskal-Wallis (F2 generation) test for multiple comparisons or the Wilcoxon-Mann-Whitney two-sample rank test. Reproduction indices and the total number of live and dead pups were analyzed by the Cochran-Armitage test for trend and Fisher-Irwin exact test for heterogeneity.

Reproductive indices:

Mating = number of females mated( =number of females with vaginal sperm or plug, or
that gave birth to a litter)x100/ number of females placed with males

Female fertility = number of females pregnant(=number of females that gave birth to a litter )x100/
number of females mated

Male fertility = number of males shown to be fertile(=a female giving birth to a litter)x100 /
number of males placed with females

Gestation = number of live litters born x100/ number of pregnant females

Offspring viability indices:

Viability * = (number of pups surviving to Day 4)x100/ number of pups born alive

Weaning+ = (number of pups surviving to Day 21)x100/ number of pups alive at Day 4 postculling

Sex ratio = ( number of male pups )x100/ total number of pups

* Also reported as “Survivability Days 0-4”
+ Also reported as “Survivability Days 4 (postculling)-21”

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Description (incidence and severity):

There were no treatment-related clinical observations for F0 males and females. Alopecia was noted with similar frequency in the control and treated groups.A common occurence in rodents maintained on ground feed is malocclusion. No parental females (F0) aborted or had physical or behavioral abnormalities during F1 gestation and lactation.

Dermal irritation (if dermal study):

not examined

Mortality:

mortality observed, non-treatment-related

Description (incidence):

Survival was 100% for all groups of males and females at termination of the F0 generation animals except for the high-dose males where it was 97%. One male in this group (Animal No. C25201) was sacrificed at Week 10 in moribund condition due to an apparent fracture of the nasal bones.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Dose levels of 0.5% and 1.0% caused a reduction in body weight for the F0 males and the values were statistically significant at Weeks 9, 10, 18 and 19 for the 1.0% dose level and at Week 17 for the 0.5% dose level. No effect on body weight was seen for females at any dose level during the premating phase or during gestation. Although body weights for females during lactation were slightly lower than those of controls, the differences were not statistically significant.
There were no consistent significant differences in body weight gains for males. Body weight gains for 1.0% dose level females during Gestation Days 14 to 20 and 0 to 20 were significantly lower than those of controls .

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Although food consumptions for treated males were slightly lower than those of controls throughout the premating phase, these differences were significant only during Week 4 for the 0.5% dose level and during Weeks 4 and 5 for the 1.0% dose level. Food consumptions for 1.0% dose level females were lower than those of controls throughout lactation and statistically significant for all intervals except Days 10 through 14 and Days 17 through 21.
Compound consumption across groups was approximately proportional to the level of DSS administered in the test diets. As one would expect, it was decreased during the premating growth phase for both sexes(although to a greater extent in males ), remained low during gestation, and then increased appreciably during lactation.

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Description (incidence and severity):

There were no significant differences from the control group for male fertility indices during breeding for F1 litters. Fertility in males was defined by a female giving birth to a litter.
No significant differences from controls were observed for mating, fertility, or gestation indices, days required to mate, or the length of gestation. No parental females aborted or had physical or behavioral abnormalities during F1 gestation and lactation.

Details on results (P0)

BODY WEIGHT (PARENTAL ANIMALS)

Table 1.Parental Body weights
Dose: 0 0.1% 0.5% 1%
Males Generation
Premating (age)
- Initial F0 (7 weeks) 232 238 241 238
F1 (6 weeks) 149 156 144 131*
F2 (7 weeks) 206 217 197 180
- Final F0 506 507 493 479
F1 510 512 492 447*
F2 531 536 492* 467*
Females
Premating
- Initial F0 (7 weeks) 165 163 165 166
F1 (6 weeks) 127 129 121 114*
F2 (7 weeks) 160 162 148 145
- Final F0 206 204 204 206
F1 281 296 271 255*
F2 285 290 271 269*
Gestation
- Initial F0 218 217 216 218
F1 278 294 267 258*
F2 288 291 277 270
- Final F0 361 365 360 350
F1 396 107 379 369*
F2 401 405 392 378*
Lactation
- Initial F0 280 280 275 267
F1 309 319 292 283*
F2 320 317 305 283*
- Final F0 288 294 290 273
F1 304 319 302 293
F2 313 316 314 300
* p < 0.05 (One-way ANOVA variance)

Effect levels (P0)

1

Dose descriptor:

NOAEC

Remarks:

Generat: maternal/paternal toxicity

Effect level:

0.1 other: %

Based on:

act. ingr.

Remarks:

in the diet

Sex:

male/female

Basis for effect level:

body weight and weight gain

2

Key result

Dose descriptor:

NOAEC

Remarks:

reproduction/offspring

Effect level:

1 other: %

Based on:

act. ingr.

Remarks:

in the diet

Sex:

male/female

Basis for effect level:

other: no effects up to highest concentration

Results: P1 (second parental generation)

General toxicity (P1)

Clinical signs:

no effects observed

Description (incidence and severity):

There were no treatment-related clinical observations for F1 males and females. Alopecia was noted with similar frequency in the control and treated groups .
As in the F0 generation, there were several instances of malocclusion and/or related signs. When necessary, the incisors of affected animals were clipped to alleviate the condition.
No parental females (F1) aborted or had physical or behavioral abnormalities during F2 gestation and lactation.

Dermal irritation (if dermal study):

not examined

Mortality:

no mortality observed

Description (incidence):

Survival was 100% for all groups of males and females at termination of the F1 generation animals.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Body weights for F1 males and females at the 1.0% dose levels were significantly lower than those of controls throughout the premating phase, excluding Week 2 for females, and throughout the treatment period for males. Body weights for F1 males and females in the 0.5%. dose group were also low (although not statistically significant) during the entire premating phase.
Gestation body weights tor females were significantly lower than those of controls at the1.0% dose level throughout gestation. Body weights during lactation were significantly lower on days 0, 7, and 14 at the 1.0% dose level; body weights on Lactation Day 21 at the 1.0% dose level were also lower than those of controls, although this difference was not statistically significant.
Body weight gains were significantly lower than those of controls during Weeks 5 and 6 for males and during Weeks 3, 5, and 8 for females at the 1.0% dose level, and during Weeks 5 and 10 for females at the 0.5% dose level.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Food consumptions were significantly lower than those of controls throughout the premating phase· (except f or Week 3) for males at the 1.0% dose level, and during Weeks 6 through 9 for males at the 0.5% dose level. Female food consumptions were significantly lower than those of controls during Weeks 7 and 8 at both the 0.5% and 1.0% dose levels.
Food consumptions during gestation were significantly greater than those of control only during Days 0 through 4 at the 0.1% dose level. Food consumptions during lactation were significantly lower during Days 7 through 10 at the 0.5% dose level, and during Days 4 through 7, 7 through 10, and 14 through 17 at the 1.0% dose level.

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Description (incidence and severity):

There were no treatment-related macroscopic observations in any animals examined in the study (F0, F1 and F2 adults and F3 weanlings).

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Reproductive function / performance (P1)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Description (incidence and severity):

There were no significant differences from the control group for male fertility indices during breeding for F2 litters .
No significant differences from controls were observed for mating, fertility, or gestation indices, days required to mate, or the length of gestation. No parental females aborted or had physical or behavioral abnormalities during F2 gestation and lactation.

Effect levels (P1)

1

Dose descriptor:

NOAEC

Remarks:

maternal/paternal toxicity

Effect level:

0.1 other: %

Based on:

act. ingr.

Remarks:

diet

Sex:

male/female

Basis for effect level:

body weight and weight gain

2

Key result

Dose descriptor:

NOAEC

Remarks:

reproduction/offspring

Effect level:

1 other: %

Based on:

act. ingr.

Remarks:

diet

Sex:

male/female

Basis for effect level:

other: no effects up to highest concentration

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Description (incidence and severity):

No significant differences from controls were observed for the total and mean number of pups born alive, litter size, survivability, or sex ratio. No pups from F1 litters had external abnormalities.

Dermal irritation (if dermal study):

not examined

Mortality / viability:

no mortality observed

Description (incidence and severity):

No significant differences from controls were observed for the total and mean number of pups born alive, litter size, survivability, or sex ratio.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Male and female pup weights on days 4, 7, 14, and 21 and pup weight gains from Days 0 through 4, 4 through 7, 7 through 14, and 14 through 21 at the 1.0% dose level were significantly lower than those of controls. Male and female pup weights on day 21 and weight gains from Days 7 through 14 (females only), and from days 14 through 21 (males and females) for the 0.5% dose level were significantly lower than those of controls.

Food consumption and compound intake (if feeding study):

not examined

Description (incidence and severity):

Pups were allowed to nurse for 21 days before weaning. Food consumption after weaning is described under the parental generation.

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Description (incidence and severity):

No pups from F1 litters had external abnormalities.

Histopathological findings:

not examined

Developmental neurotoxicity (F1)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F1)

Developmental immunotoxicity:

not examined

Details on results (F1)

BODY WEIGHT (OFFSPRING)

Table 2.Offspring Body weights
Dose: 0 0.1% 0.5% 1%
Males
- Day 0 F1 6.5 6.8 6.4 6.6
F2 6.5 6.7 6.4 6.3
F3 6.7 6.7 6.8 6.1*
- Day 21 F1 15.6 14.7 13.7* 11.5*
F2 17.7 17.8 14.8* 12.4*
F3 19.7 19.9 17.6 13.4*
Females
- Day 0 F1 6.2 6.4 6.1 6.2
F2 6.1 6.4 6.1 6.0
F3 6.4 6.4 6.4 5.8*
- Day 21 F1 15.4 14.74 13.1* 10.8*
F2 16.5 17.1 14.5 11.4*
F3 18.6 19.3 16.0* 12.9*
* p < 0.05 (One-way ANOVA variance)

Effect levels (F1)

Dose descriptor:

NOAEC

Generation:

F1

Effect level:

0.1 other: %

Based on:

act. ingr.

Remarks:

diet

Sex:

male/female

Basis for effect level:

body weight and weight gain

Results: F2 generation

General toxicity (F2)

Clinical signs:

no effects observed

Description (incidence and severity):

No significant differences from controls were observed for the total and mean number of pups born alive, litter size, survivability, or sex ratio.
Alopecia, tremors, and rough hair coat were recorded on day 21 for three pups (two males and one female) from one F2 litter at the 0.5% dose level.

Dermal irritation (if dermal study):

not examined

Mortality / viability:

no mortality observed

Description (incidence and severity):

No significant differences from controls were observed for the total and mean number of pups born alive, litter size, survivability, or sex ratio.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Beginning on day 7, male and female pup weights and pup weight gains at the 0.5% and 1.0% dose levels were consistently lower than those of controls; the differences were statistically significant for all values except day 7 female pup weight, male and female pup weight gains for the 0.5% dose level. On Day 4 of lactation no milk was observed in the abdomen of three pups from two litters in the control group, seven pups from five litters in the 0.1% dose group, 18 pups from 10 litters in the 0.5% dose group, and 10 pups from five litters in the 1.0% dose group.

Food consumption and compound intake (if feeding study):

not examined

Description (incidence and severity):

Pups were allowed to nurse for 21 days before weaning. Food consumption after weaning is described under the parental generation.

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Alopecia, tremors, and rough hair coat were recorded on day 21 for three pups (two males and one female) from one litter at the 0.5% dose level.

Histopathological findings:

not examined

Developmental neurotoxicity (F2)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F2)

Developmental immunotoxicity:

not examined

Details on results (F2)

See under Details on results (F1).

Effect levels (F2)

Dose descriptor:

NOAEC

Generation:

F2

Effect level:

0.1 other: %

Based on:

act. ingr.

Remarks:

diet

Sex:

male/female

Basis for effect level:

body weight and weight gain

Overall reproductive toxicity

Key result

Reproductive effects observed:

no

Lowest effective dose / conc.:

1 other: %

Any other information on results incl. tables

Extension on the F2 parents to generate an F3 litter generation:

Male fertility indices at the 0.5% and 1.0% dose levels during breeding for F3 litters were significantly higher than that of the control group.

No significant differences from controls were observed for mating, fertility, or gestation indices, days required to mate, or the length of gestation. No parental females aborted or had physical or behavioral abnormalities during F3 gestation and lactation.

Body weights for males were significantly lower than those of controls throughout the treatment period at the 1.0%; dose level, and from Week 3 through the duration of the treatment period for males at t he 0.5%; dose level. Body weights were significantly lower than those of controls for F2 females at the 1.0% dose level throughout the premating phase (except Weeks 0 and 2} , and during Weeks 1, 3 through 6, and 8 for females at the 0.5% dose level.

Gestation body weights were significantly lower than those of controls at the 1.0% dose level throughout gestation. Body weights during lactation were significantly lower on Days 0, 7, and 14 at the 1.0% dose level; mean body weight on lactation Day 21 at the 1.0% dose level also was lower than that of the control, although this difference was not statistically significant.

Body weight gains were significantly lower than these of controls during weeks 4, 5 through 8, 13, 15, 17 , 20, 23, and 24 formales at the 1.0% dose level , during Weeks 4, 6, 7, 13, 16, 23, and 24 for males at the 0.5% dose level, and during Week 3 for males at the 0.1% dose level. There were no consistent significant differences in weight gains for females during the treatment period.

Body weight gains during lactation were significantly higher than these of the control between Days 14 and 21 at the 1.0% dose level, and between Days 0 and 21 for the 0.5% and 1.0% dose levels.

Food consumptions were significantly lower than those of controls during Weeks 2, 5 through 7, and 10 for males at the 1.0% dose level, and during Weeks 5 through 7 for males at the 0.5% dose level, Female food consumptions were significantly lower than those of controls during Week 2 at both the 0.5% and 1.0% dose levels, and were significantly higher during Week 7 at the 0.1% dose level.

F3 Litter data:

No significant differences from controls were observed for the mean number of pups born alive, litter size, survivability, or sex ratio. The proportions of the total number of pups born alive and found dead at the 1.0% dose level were significantly lower and higher, respectively, than those of the controls. These differences may merely reflect the effect of a slight reduction in the number of litters in the control group, and a disproportionate influence of very few litters in the high-dose group; i.e. , two litters accounted for 13 (six plus seven) of the 17 pups found dead; there was one dead pup each in four other litters. Male and female pup weights and pup weight gains at the 1.0% dose level were significantly lower than these of controls throughout lactation. At the 0.5% dose level, pup weight gains for males and females from Days 4 through 7, for males from Days 7 through 14, and tor fema1es from Days 14 through 21 were significantly lower than these of the control, as were male pup weights on Day 14 and male and female pup weights on Day 21. One pup in the0.5% dose group and 17 pups from seven litters In the 1.0% dose group had no milk in the abdomen on Day 4 of lactation. One female pup in the control group was icteric on Day 4. Another control pup from a different litter was missing the left eye. Five males and five females from one litter at the 1.0% dose level had urine stains on Day 21.

Applicant's summary and conclusion

Conclusions:

DSS administered in the diet to three successive generations of rats at levels of 0.5% and 1.0% caused a reduction in body weights for parental males of all generations and for F1 and F2 females. Pup weights at the 0.5% and 1.0% dose levels were lower than those of the control in all three generations. However, the reduced body weight did not interfere with growth and development or reproductive performance, and the test substance had no adverse effects at levels on the reproductive function of either sex in any generation up to 1% in the diet.
Based on the results of this study, when DSS was administered in the diet to three succesive generations of rats, the no-observable-effect level (NOEL) for body weights of parental animals and offspring was 0.1%; the NOEL for reproductive parameters was 1.0% DSS.

Executive summary:

Docusate sodium was administered in the diet to three successive generations at levels of 0.1%, 0.5% and 1.0% in the diets of 30 males and 30 females per group, dosed for 10 and 2 weeks respectively. The dose levels of 0.5% and 1.0% caused a reduction in body weights for parental males of all generations and for F1 and F2 females. Pup weights at the 0.5% and 1.0% dose levels were lower than those of the control in all three generations. However, the reduced body weight did not interfere with growth and development or reproductive performance, and the test substance had no adverse effects at levels on the reproductive function of either sex in any generation up to 1.0% in the diet. There were no other effects on parental or reproductive parameters.

Based on the results of this study, when DSS was administered in the diet to three succesive generations of rats, the no-observable-effect level (NOEL) for body weights of parental animals and offspring was 0.1%; the NOEL for reproductive parameters was 1.0% DSS.