Octanoic acid, esters with anhydrosorbitol and dianhydrosorbitol

Toxicity to reproduction

Administrative data

Endpoint:

multi-generation reproductive toxicity

Remarks:

based on test type (migrated information)

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Justification of read-across: Both chemicals are of comparable structures with minor deviations and can be characterized as an ester of sorbitan and a fatty acid. Justification of reliability of 2: scientifically well-performed study

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Unnamed

Year:

1956

Report date:

1956

Reference 2

Reference Type:

publication

Title:

Unnamed

Year:

1957

Report date:

1956

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 416 (Two-Generation Reproduction Toxicity Study)

Deviations:

yes

Remarks:

4 generations investigated

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Sorbitan stearate

EC Number:

215-664-9

EC Name:

Sorbitan stearate

Cas Number:

1338-41-6

IUPAC Name:

1,4-anhydro-6-O-stearoyl-D-glucitol

Constituent 2

Reference substance name:

Sorbitan monostearate

IUPAC Name:

Sorbitan monostearate

Constituent 3

Reference substance name:

Span 60

IUPAC Name:

Span 60

Test material form:

not specified

Details on test material:

- Name of test material (as cited in study report): Span 60

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Food Research Laboratories
- Age at study initiation: 4 x wks; (F1) x wks
- Weight at study initiation: 50-70 g
- Housing: For the first 12 weeks, hosed individually, when mating, transferred to larger cages, one male housed with one or two females
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
ddddddddddad

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23-26
- Humidity (%): 40-60

Administration / exposure

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on mating procedure:

- M/F ratio per cage: 1/1 or 1/2
- Length of cohabitation: maximum 3 weeks, if pregnancy ont established, the male was replaced.
- Proof of pregnancy: bisuall, by palpation, or from weight increments
- After 21 days of unsuccessful pairing replacement of first male by another male with proven fertility.
- Further matings after two unsuccessful attempts: yes, following 3 (occasionally 4) unproductive tirals with females of knon fertility, males were considered sterile and retired. Females were continued for a minimum of 6 matings with fertile males, even though somne failures may have intervened.
- After successful mating each pregnant female was caged (how): individually

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

2 years

Frequency of treatment:

feed, continuously

Details on study schedule:

- F1 parental animals not mated until 17 weeks after selected from the F1 litters.
- Selection of parents from F1 generation when pups were 49 days of age.
- Age at mating of the mated animals in the study: 17 weeks

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 5, 10, 20 %
Basis:
nominal in diet

No. of animals per sex per dose:

12 males, 20 females

Control animals:

yes, plain diet

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: no data
- Cage side observations checked: physical appearance, behavior, laxation and water consumption.

DETAILED CLINICAL OBSERVATIONS: No data

BODY WEIGHT: Yes
- Time schedule for examinations: weekly during the first 12 weeks, biweeksly thereafter

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for 5 animals each sex determined for the first 12 weeks, and for a two week period at the 0.5 1, 1.5, and 2-year stages in the initial generation and for 12 weeks after weaning in succeeding generations.
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals
- Maternal animals: All surviving animals

GROSS NECROPSY
- all animals

HISTOPATHOLOGY / ORGAN WEIGHTS
The tissues: kidney and liver, other organs were examined microscopically where indicated by their gross appearance and in at leat two apparently normal rats of each sex randomly selected from the 20% groups.

Postmortem examinations (offspring):

SACRIFICE
- Male animals: All surviving animals
- Maternal animals: All surviving animals

GROSS NECROPSY
- all animals

HISTOPATHOLOGY / ORGAN WEIGHTS
The tissues: kidney and liver, other organs (stomach, thyroid, gonads, lymph nodes, bone marrow and spinal cord) were examined microscopically where indicated by their gross appearance and in at leat two apparently normal rats of each sex randomly selected from the 20% groups.

Reproductive indices:

fertility index (F.I.), the percentage of matings resulting in pregnancy;
gestation index (G.I.), the percentage of pregnancies resulting in the birth of live litters;

Offspring viability indices:

viability index (V.l.), the percentage of rats born that survived 4 days or longer;
lactation in dex (L.I.), the percentage of rats alive at 4 days that survived the 21-day lactation period.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

body weight reduced in 20% group

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

body weight reduced in 20% group

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Other effects:

no effects observed

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)

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
- no effect

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS)
- in the 20% dose group of males, the body weight gain in 12-week was lower than control group
- no effect in food consumption

ORGAN WEIGHTS (PARENTAL ANIMALS), GROSS PATHOLOGY (PARENTAL ANIMALS), HISTOPATHOLOGY (PARENTAL ANIMALS):

- In 20% group, liver enlargement was observed; histopathologically these livers showed moderate central or lobular necrosis.
- In 10 and 20% group, the kidney weighs were increased; but no organic changes were seen microscopically in there kidneys.
- No treatment related effect in other organs examined (stomach, thyroid, gonads, lymph nodes, bone marrow and spinal cord).

Blood observations
The blood hemoglobin levels were within the normal range throughout the entire test and for all groups,
The mean values for total leukocyte counts fell within normal limits. No evidence of eosinophilia was observed although the counts varied within rather wide limits.
No deviations from the ranges of normal blood sugar valueswere found
The average cholesterol levels were normal regardless of the duration of the feeding period or the diet fed and that no trend either upward or downward was observed from one generation to another.

Urine examinations.
The presence of oxalates in the two-year urine specimens was not significantly increased.

Digestibility of fatty acid moieties examination:
The coefficient of digestibility of the test tem was found to be 53.5, and this value was used in computing the caloric value of the supplemented diets for the animals.

Effect levels (P0)

1

Dose descriptor:

LOAEL

Effect level:

10 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: body weight change, liver enlargement

2

Dose descriptor:

NOAEL

Effect level:

5 000 mg/kg bw/day

Based on:

test mat.

3

Dose descriptor:

LOAEL

Effect level:

10 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: decreased reproductive performance and pregnancy rate.

Remarks on result:

other: Generation: F1-F3 (migrated information)

4

Dose descriptor:

NOAEL

Effect level:

5 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Remarks on result:

other: Generation: F1-F3 (migrated information)

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

mortality observed, treatment-related

Body weight and weight changes:

no effects observed

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

effects observed, treatment-related

Histopathological findings:

effects observed, treatment-related

Details on results (F1)

VIABILITY (OFFSPRING)
significant reduction in survival of new born (F1) in 20% group.


ORGAN WEIGHTS (OFFSPRING), GROSS PATHOLOGY (OFFSPRING), HISTOPATHOLOGY (OFFSPRING):

- In 20% group, liver enlargement was observed; histopathologically these livers showed moderate central or lobular necrosis.
- In 10 and 20% group, the kidney weighs were increased; but no organic changes were seen microscopically in there kidneys.
- No treatment related effect in other organs examined (stomach, thyroid, gonads, lymph nodes, bone marrow and spinal cord).

OTHER FINDINGS (OFFSPRING)
- comparision of the reproduction data of F0, F1 and F2, the responses of repruduction in the three successive generations were quite similar.
- the third generation was generally less productive than the first two may be seen in the lower F.I. values
- The trend toward higher mortality during the 4 days post partum as the level of emulsifier increased, was not as marked in the F1 and F2 as in the F0 generation.
- The proportions of matings resulting in pregnancy were lowe in the 20% dietary ester group. The proportion of nurslings surviving the lactation period was reduced in some cases in the F2 generation at the 20% level
- Reproductive performance in general appeared to be inferior in the third generation rats compared to their progenitors.
- The reproductive performance of the F3 generation was not investigated because the rats in this generation were sacrificed either at weaning or at the end of the 12-week growth period.
- Decreased growth and viability were noted in offspring born to dams treated at 20% level.
- Further experiments indicated that the most common finding appeared to be improved viability of the newborn when the fat level of the 20% diets was increased by the addition of 9% of vegetable fat.

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

The analogue approach using sorbitan stearate as source chemical is justified:

Both chemicals are of comparable structures with minor deviations and can be characterized as an ester of sorbitan and a fatty acid. Compared to the source chemical, the target chemical has a shorter alkyl chains that affect its physicochemical properties. But based on the kinetic / metabolic investigations on both chemicals, the length of the alkyl chain is not considered to have significant impact on the metabolic pathway or toxicological mode of action. Oral gavage studies in rats administered C14 labeled sorbitan stearate in oil solutions have demonstrated that about 90% of the substance was absorbed and hydrolyzed to stearic acid and sorbitan. The metabolic fate of sorbitan caprylate was investigated using a lipase assay. The hydrolysis mediated by porcine pancreas lipase was quantitatively determined. The target chemical sorbitan caprylate is proved to be hydrolyzed and caprylic acid was formed . These findings suggest that metabolism of the sorbitan occur initially via enzymatic hydrolysis, leading to sorbitan and the corresponding natural acids.

Based on the above mentioned information, it is reasonable to consider that these two substances are comparable in their metabolic fate and thereby toxicological profiles. Hence, the source chemical is considered as “suitable with interpretation” analog.

According to the available toxicity studies, the findings are also comparable for target and source chemicals:

·        The findings in acute toxicity studies are comparable. Both chemicals are of no acute toxicity.

·        The findings in subacute dose toxicity studies are comparable. No treatment effects were observed in 28-day repeated toxicity studies in Wistar rats. The same NOEL of 1000 mg/kg bw/d was derived for both chemicals.

·        The findings in genetic toxicity are comparable. Both chemicals did not induce gene mutations in Ames tests, but induced structural chromosomal aberrations in cell lines of Chinese Hamster.

·        The findings in reproduction / developmental toxicity studies are comparable.

Blood observations

The blood hemoglobin levels were within the normal range throughout the entire test and for all groups,

The mean values for total leukocyte counts fell within normal limits. No evidence of eosinophilia was observed although the counts varied within rather wide limits.

No deviations from the ranges of normal blood sugar valueswere found

The average cholesterol levels were normal regardless of the duration of the feeding period or the diet fed and that no trend either upward or downward was observed from one generation to another.

Urine examinations.

The presence of oxalates in the two-year urine specimens was not significantly increased.

Digestibility of fatty acid moieties examination:

The coefficient of digestibility of the test tem was found to be 53.5, and this value was used in computing the caloric value of the supplemented diets for the animals.

Others see Remarks

Applicant's summary and conclusion

Conclusions:

The LOAEL and NOAEL of the target chemical are considered to be 10000 and 5000 mg/kg bw/day, respectively.

Executive summary:

The reproduction toxicity of sorbitan caprylate was assessed based on the analogue approach using sorbitan monostearate as a read-across supporting substance.

Wistar rats (25 groups consisting of 12 males and 20 females/dose; F0 generation) were administered with sorbitan monostearate in the diet at 0, 5, 10 or 20% (~ 0, 2500, 5000 or 10,000 mg/kg-bw/day) for two years (spanning four generations). During the course of the study, observations were made of physical appearance, behavior, reproduction, and lactation through three successive generations, and gross and histologic evaluations were made at termination. Growth was normal, except for males in the 20 percent group. These animals had reduced weight gains. Fertility and gestation parameters for the initial generation were similar for control and test groups. Infant deaths for the 10 and 20 percent ester groups were higher than for the control group which was considered to be due to maternal neglect and reduced milk production. Reproduction and lactation data were also recorded for the F1 and F2 generations. The proportions of matings resulting in pregnancy were lower in the 20 percent dietary ester group, as was the proportion of nurselings surviving the lactation period. No deviation from the normal range was found in hemoglobin values, leukocyte counts, blood sugar, or plasma cholesterol values. Urinalysis after 1 and 2 years had sporadic positive tests for the presence of albumin and reducing sugars. No striking differences in number of deaths in any group were found up to 1% years. However, during the last quarter of the study the number of deaths was greater for the 20 percent group. Lungs of both test and control animals were congested. In rats of the 10 and 20 percent ester groups, the livers were enlarged, but the incidence of hepatic necrosis was no greater in these groups than in lower dosed groups or controls. Also at the two higher dietary concentrations, the weights of the kidneys were increased, but no microscopic changes were observed. The stomach, GI tract, heart, spleen, pancreas, adrenals, thyroid, gonads, lymph nodes, bone marrow, and spinal cord had no compound-related lesions. The investigators concluded that chronic consumption of a few tenths of 1 percent of Sorbitan Stearate would pose no hazard to human health.

Based on the result, it was concluded:

LOAEL (maternal toxicity) ~10,000 mg/kg-bw/day (based on body weight change, liver enlargement)

NOAEL (maternal toxicity) ~ 5,000 mg/kg-bw/day

LOAEL (reproductive toxicity) ~ 10,000 mg/kg-bw/day (based on decreased reproductive performance and pregnancy rate)

NOAEL (reproductive toxicity) ~ 5,000 mg/kg-bw/day

LOAEL (developmental toxicity) ~ 10,000 mg/kg-bw/day (based on decreased growth of offspring)

NOAEL (developmental toxicity) ~ 5,000 mg/kg-bw/day