Branched and linear octadecanoic acid, esters with glycerol oligomers

Toxicity to reproduction

Some information in this page has been claimed confidential.

Administrative data

Endpoint:

three-generation reproductive toxicity

Type of information:

read-across from similar mixture/product

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable publication which meets basic scientific principles.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1998

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

A three-generation reproduction study was conducted on polyglycerol polyricinoleate (PGPR) to investigate the potential adverse effects on reproduction. Breeding was conducted using a continuous breeding protocol in which pairs of animals were maintained until each female had produced five litters (or it became evident that breeding had ceased). This procedure was repeated over three generations. The main focus of the study design was to observe any effect on breeding. This study was conducted during the late 1950s/early1960s and the methods represented the state of the art which existed during this period. The study nevertheless allow an adequate assessment of the potential reproductive and chronic toxicity of PGPR.

GLP compliance:

no

Limit test:

yes

Test material

Test material information

Constituent 1

Test animals

Species:

rat

Strain:

other: Colworth Wistar rats

Details on species / strain selection:

No details given.

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: breeding facility at the Unilever Colworth Laboratory, Sharnbrook, Bedford, UK
- Diet: commercial pelleted stock diet (Spital), ad libitum
- Water: ad libitum

Administration / exposure

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): each week
- Mixing appropriate amounts with (Type of food): PGPR was incorporated into the ground diet first by hand followed by mixing in a mechanical mixer.

Details on mating procedure:

- M/F ratio per cage: 1/1
- Length of cohabitation: One male and one female were cohoused until succesful mating was determined. The respective mating couples were maintained for 5 reproduction cycles or until such time as it became evident that breeding had ceased.

Analytical verification of doses or concentrations:

no

Details on analytical verification of doses or concentrations:

No analytical verification conducted.

Duration of treatment / exposure:

Continuously with diet and via mother's milk.

Frequency of treatment:

Continuously with diet and via mother's milk.

Details on study schedule:

The first-generation parents (P0) were selected from five litters which were assigned randomly into two groups: a control (11 males and 17 females) and a treatment group fed 1.5% PGPR (six males and 13 females). All rats were weaned at 23 days and mated at 121 days. Breeding was continuous and the males were only separated from the females when it was apparent that the female was pregnant. In all instances the first litters were discarded after weaning and second-generation breeders (F1) were randomly selected (two males and two females) from each of the second and fourth litters. By selecting from two first-generation litters the number of animals was increased to 52 of each sex in the control and 32 of each sex in the PGPR group. The third-generation breeders (F2) were selected in a similar manner, by which the control and the PGPR groups were increased to 92 and 44 rats of each sex, respectively. The large control groups were considered necessary to get an indication of the variations in breeding results that occur within a normal breeding colony.

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

1.5 other: % (w/w)

Doses / concentrations 2

Dose / conc.:

2 000 mg/kg bw/day (nominal)

Remarks:

(the breeding females consumed PGPR at levels > 2 g/kg bw/day (based on a food intake level of up to 40 g/day during lactation and the inclusion of PGPR in the diet at the fixed level of 1.5%))

No. of animals per sex per dose:

- 1st generation (P0): 11 males / 17 females (control group); 6 males / 13 females (treatment group)
- 2nd generation (F1): 52 males / 52 females (control grooup); 32 males / 32 females (treatment group)
- 3rd generation (F2): 92 males / 92 females (contro group); 44 males / 44 females (treatment group)

Control animals:

yes, plain diet

Details on study design:

- Dose selection rationale: The dietary level of 1.5% PGPR was chosen to provide an intake by the pregnant and lactating rat which was in excess of 150 times the intake of a person consuming 5 mg PGPR/kg bw/day.

Positive control:

No

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: daily

BODY WEIGHT: Yes
- Time schedule for examinations: Growth was monitored from weaning to mating during the first 4 months of each generation. The weights of the females were recorded at weaning and mating, while the weight of the males was recorded at weaning and day 65.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Food intakes were not recorded in this study, but it has been shown in an earlier publication that levels of 5% PGPR in the diet has no effect on food intake.

Oestrous cyclicity (parental animals):

Not examined.

Sperm parameters (parental animals):

Not examined.

Litter observations:

PARAMETERS EXAMINED
The following parameters were examined in the 3 generations:
number of litters per dam, average litter size, average weaning weights of males and females, litters per group showing 100% survival and total survival (%) at day 21

Postmortem examinations (parental animals):

Not examined.

Postmortem examinations (offspring):

Not examined.

Statistics:

A Student's t-test was conducted in which the two groups were compared.

Reproductive indices:

No data.

Offspring viability indices:

No data.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Other effects:

not examined

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Details on results (P0)

- GROWTH:
There were no significant differences in clinical signs in treated or control rats which indicated a treatment-related effect of PGPR.

- SURVIVAL AND CLINICAL SIGNS:
There were no deaths during the experimental period and no evidence of abnormal behaviour or functional disorder associated with the consumption of PGPR.

- BREEDING PERFORMANCDE:
Breeding performance for both the control and PGPR groups appeared to be more successful in the first generation (P0) as in the second generation (F1). In generation 1 (P0) a high percentage of the offspring was weaned for both groups.

Effect levels (P0)

Key result

Dose descriptor:

NOAEL

Remarks:

(systemic/fertility)

Effect level:

>= 2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

other: (corresponding to 1.5%)

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not examined

Histopathological findings:

no effects observed

Description (incidence and severity):

A histological examination of selected tissues from the rats of the second generation which showed a reduction in the percentage of animals weaned failed to show any lesions which could be ascribed to the consumption of PGPR.

Other effects:

not examined

Developmental neurotoxicity (F1)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F1)

Developmental immunotoxicity:

not examined

Details on results (F1)

- GROWTH:
There were no significant differences in clinical signs in treated or control rats which indicated a treatment-related effect.

- SURVIVAL AND CLINICAL SIGNS:
There were no deaths during the experimental period and no evidence of abnormal behaviour or functional disorder associated with the consumption of PGPR.

- BREEDING PERFORMANCE:
In the second generation (F1), breeding performance was poor for both diets with the only signifcant difference being that control rats had a signifcantly greater percentage of litters weaned entirely, which was reversed to the PGPR rats in the third generation (F2). An increase in the number of females which failed to breed was evident in the second generation (F1) compared to the first generation (P0). However, as the number of females failing to breed is comparable between the treatment and control group, the decrease in breeding success is not considered as related to test substance intake. One further difference in the second generation (F1) was the higher proportion of males among the weaned rats fed PGPR. As rats were not sexed until weaning, it is not known if this is due to a higher proportion of males being born, or to the males surviving better than the females. In the second generation (F1) there was a reduction in the percentage of animals weaned. As this reduction occurred in both groups and to a similar extent it is concluded that this was due to an unknown environmental factor.

- HISTOPATHOLOGY:
A histological examination of selected tissues from the rats of the second generation (F1) which showed a reduction in the percentage of animals weaned continued for 1 year failed to show any lesions which could be ascribed to the consumption of PGPR.

Effect levels (F1)

Key result

Dose descriptor:

NOAEL

Remarks:

(systemic/fertility)

Generation:

F1

Effect level:

>= 2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

other: (corresponding to 1.5%)

Results: F2 generation

General toxicity (F2)

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not examined

Histopathological findings:

not examined

Other effects:

not examined

Developmental neurotoxicity (F2)

Behaviour (functional findings):

not examined

Developmental immunotoxicity (F2)

Developmental immunotoxicity:

not examined

Details on results (F2)

- GROWTH:
There were no significant differences in clinical signs in treated or control rats which indicated a treatment-related effect of PGPR.

- SURVIVAL AND CLINICAL SIGNS:
There were no deaths during the experimental period and no evidence of abnormal behaviour or functional disorder associated with the consumption of PGPR.

- BREEDING PERFORMANCE:
Breeding performance for both the control and PGPR groups appeared to be more successful in the third generation (F2) as in the second generation (F1). In
generation 3 (F2) a high percentage of the offspring were weaned for both groups. An increase in the number of females which failed to breed was evident in the third generation (F2) compared to the first generation (P0). However, as the number of females failing to breed is comparable between the respective treatment and control group, the decrease in breeding success is not considered as related to test substance intake.

Effect levels (F2)

Key result

Dose descriptor:

NOAEL

Remarks:

(systemic/fertility)

Generation:

F2

Effect level:

>= 2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

other: (corresponding to 1.5%)

Overall reproductive toxicity

Reproductive effects observed:

no

Any other information on results incl. tables

In conclusion, the similarity observed between the data obtained for the first (P0) and third generations (F2) failed to provide any evidence of a cumulative effect due to long-term ingestion of PGPR over three successive generations.