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Toxicological information

Toxicity to reproduction

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Administrative data

Endpoint:
three-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:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Hypothesis for the analogue approach: This read-across is based on the hypothesis that source and target substances have similar toxicological properties because, following oral intake, the source substances hydrolyse in the gut to non-common products predicted to have no toxicological effect (metabolic approach). The target substance is n-nonanoic acid, a saturated linear, medium-chain length carboxylic acid. The prediction is limited for saturated linear, medium-chain length carboxylic acids as source substances and for systemic toxicity endpoints, e.g. repeated dose toxicity and toxicity to reproduction. The prediction is supported by valid toxicological data on the substances and their hydrolysis products, based on known rapid and extensive hydrolysis and subsequent metabolism. For read across justification, see the atteched file in endpoint 13 ( Analogue approach justification): Acceptable, well-documented publication which meets basic scientific principles

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1993

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 416 (Two-Generation Reproduction Toxicity Study)
Deviations:
yes
Remarks:
3 generations; lower animal numbers;
GLP compliance:
not specified
Limit test:
yes

Test material

Constituent 1
Reference substance name:
cuphea oil
IUPAC Name:
cuphea oil
Constituent 2
Reference substance name:
Cuphea oil
IUPAC Name:
Cuphea oil
Details on test material:
- Name of test material (as cited in study report): cuphea oil
- Molecular formula (if other than submission substance): triglyceride
- Fatty acid composition:
octanoate 4.8%
decanoate 75.9%
dodecanoate 2.5%
myristate 2.2%
palmitate 3.4%
stearate 0.7%
oleate 3.3%
linoleate 5.5%h
- Composition of test material, percentage of components: see above; analysed using gas chromatography


Test animals

Species:
mouse
Strain:
other: two strains were tested: CBA/2 and C57B1/6
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source:
- Age at study initiation: (P) 8-10 wks; (F1, F2) 8-10 wks
- Housing:
P: two females and one male together; females singly when vaginal plug was observed
F1, F2: weaned at 4 weeks, then housed together until sexual maturation, mating two females: one male. Females tehn hosued singly.
Males of each generation housed singly an dfed for 13 weeks; some males were fed for 5-12 months

- Diet: ad libitum
Feeding: Cuphea oil was limited, schedule was therefore as follows:
Strain 57B1/6:
F1: 10 months
F2: 8 months
F3: 11-12 months

Strain CBA/2:
F1: 11-12 months
F2: 9-11 months
F3: 6-8 months

- Water: ad libitum

Administration / exposure

Route of administration:
oral: feed
Vehicle:
other: basal diet
Details on exposure:
DIET PREPARATION
- Rate of preparation of diet (frequency):
- Mixing appropriate amounts with (Type of food): basal diet with reduced beef tallow 886 g/kg instead of 172g/kg)
- Storage temperature of food:

VEHICLE
- Justification for use and choice of vehicle basal diet was chosen for the feeding study. Compsoition described in Table 1
- Concentration in vehicle: 8.6% Cuphea oil
Details on mating procedure:
- M/F ratio per cage: 1:2
- Length of cohabitation: until vaginary plug was noted
- Proof of pregnancy: vaginal plug
- After successful mating each pregnant female was caged: singly
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
GC determination of atty acids in Cuphea oil
Duration of treatment / exposure:
Feeding: Cuphea oil was limited, schedule was therefore as foollows:
Strain 57B1/6:
F1: 10 months
F2: 8 months
F3: 11-12 months

Strain CBA/2:
F1: 11-12 months
F2: 9-11 months
F3: 6-8 months
Frequency of treatment:
7 days/week
Doses / concentrations
Remarks:
Doses / Concentrations:
8.6%
Basis:
nominal in diet
No. of animals per sex per dose:
Strain 57B1/6: F1: 16; F2: 16; F3: 13. Controls 15-17/generation

Strain CBA/2: F1: 25; F2: 11; F3: 5. Controls 5-29/generation
Control animals:
yes, concurrent vehicle
Positive control:
not needed

Examinations

Parental animals: Observations and examinations:
CAGE SIDE OBSERVATIONS: Yes

DETAILED CLINICAL OBSERVATIONS: No data

BODY WEIGHT: Yes
- Time schedule for examinations:
Animals fed for 13 weeks: weeks 4, 8, and 13 (Table3)
Animals fed for 5-12 months: : weeks 4, 13. 26, 39, and 45 (Table 5)


FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No. total grams ingested is given (Tables 4 and 6)
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No. can be estimated.

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No. Not applicable


OTHER:
Oestrous cyclicity (parental animals):
No data
Sperm parameters (parental animals):
No data
Litter observations:
STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: no data

PARAMETERS EXAMINED
The following parameters were examined in [F1 / F2 / F3] offspring:
[number of live births, postnatal mortality, presence of gross anomalies, weight gain

GROSS EXAMINATION OF DEAD PUPS:
no
Postmortem examinations (parental animals):
no data
Postmortem examinations (offspring):
no data
Statistics:
no data
Reproductive indices:
pregnancy index (Table 2)
Offspring viability indices:
Table 2

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:
no effects observed
Body weight and weight changes:
no effects observed
Description (incidence and severity):
no consistent variations though cuphea-fed mice had slightly lower body weights and lower feed intake
Food consumption and compound intake (if feeding study):
no effects observed
Description (incidence and severity):
no consistent variations though cuphea-fed mice had slightly lower body weights and lower feed intake
Organ weight findings including organ / body weight ratios:
no effects observed
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Description (incidence and severity):
Liver: excessive lipid accumulation (liver of most mice); Kidneys: fat vacuoles in proxicmal cortical tubules of all mice; Spleen in some mic enlarged
Other effects:
no effects observed
Description (incidence and severity):
Test substance intake: no consistent variations though cuphea-fed mice had slightly lower body weights and lower feed intake

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):
table 2

Effect levels (P0)

open allclose all
Dose descriptor:
NOAEL
Effect level:
ca. 4 700 mg/kg bw/day (nominal)
Based on:
other: decanoic acid; read across
Sex:
male/female
Basis for effect level:
other: no effects was obeserved
Dose descriptor:
NOAEL
Effect level:
ca. 4 700 mg/kg bw/day (nominal)
Based on:
other: decanoic acid; read across
Sex:
male/female
Basis for effect level:
other: no adverse effects were observed
Remarks on result:
other: Generation: F3 (migrated information)

Results: F1 generation

General toxicity (F1)

Clinical signs:
not specified
Mortality / viability:
no mortality observed
Description (incidence and severity):
no effect in C57B1/6, in contrast to starin CBA/2 (strain-specific effect). Viability of pups from F1 and F2 parents reduced compard to those from F0 pups
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
reduced body weights in Cuphea fed pups
Sexual maturation:
no effects observed
Organ weight findings including organ / body weight ratios:
no effects observed
Description (incidence and severity):
comparable between grouops; where stat. significant changes were noted, Cuphea-fed mcie had lower body and liver weights
Gross pathological findings:
not specified
Histopathological findings:
effects observed, treatment-related
Description (incidence and severity):
Liver: excessive lipid accumulation (liver of most mice); Kidneys: fat vacuoles in proxicmal cortical tubules of all mice; Spleen in some mic enlarged

Effect levels (F1)

Dose descriptor:
NOAEL
Generation:
F1
Effect level:
ca. 4 700 mg/kg bw/day (nominal)
Based on:
other: decanoic acid; read across
Sex:
male/female
Basis for effect level:
other: No adverse effects were observed

Results: F2 generation

Effect levels (F2)

Dose descriptor:
NOAEL
Generation:
F2
Effect level:
ca. 4 700 mg/kg bw/day (nominal)
Based on:
other: decanoic acid; read across
Sex:
male/female
Basis for effect level:
other: No adverse effects were observed

Overall reproductive toxicity

Reproductive effects observed:
not specified

Any other information on results incl. tables

Comments to histopathology in Fo, F1, and F3 animals of both tested strains:

Liver: lipid accumulation due to fat and cholesterol content of the diets. No differences between diets and generations in fatty liver development. The two strains showed marked differences, possibly because of differences in hepatic fat metabolism.

Renal vacuolar changes: likely caused by the high total lipid content of the fee No differences between diets or generations (table 7).

Preputial glands: strain-specific differences, no effect of treatment.

Lungs:. Changes noted, but not related to treatment or strain.

 

Dose estimate of decanoic acid:

According to tble 6, the total feed intake per animal was approx. 200 g in treated animals of either strain in generations 1, 2, and 3 at 13 weeks. Assuming a mean body weight of 30 g this corresponds to 200g/90 d x (1000/30) = 74 g/kg bw and day. Cuphea oil was 8.6% in the diet, i.e. ingestion was 6365 mg Cuphea oil /kg bw and day.

Assuming a mean fatty acid chain length of 10 in the Cuphea triglycerides, the mean molecular of the triglyceride is weight is approx. 554. Decanoic acid represented 75% of the fatty acids, and represents 74% of the Cuphea oil dose, i.e. 4700 mg decanoic acid/kg bw and day.

 

 

 

 

 

 

 

Applicant's summary and conclusion

Conclusions:
Feeding Cuphea oil to mice (two strains, 3 generations each) did not affect reproduction and had no adverse effect on parental animals. Cuphea oil appears to be nontoxic, but was of no particular health benefit. Cuphea oil contained 74% of decanoic acid. The
estimated NOAEL was 4700 mg/kg bw and day for decanoic acid, and this value can also be used for nonanoic acid because both acids undergo the same metabolism.
Executive summary:

Hendrich et co-workers (1993) reported a 3 generation feeding study using two strains of mice (CBA/2 and C57B1/6). Male and female mice were used. Controls were fed a basal diet with 17.2% beef tallow and 3.5% corn oil; in the diet for treated mice 8.6% Cuphea oil replaced 50% of the beef tallow, i.e. the diets were essentially isocaloric. The triglycerides of the Cuphea oil contained 75% decanoic acid, 4.8% octanoic acid, and small proportions of some long chain fatty acids.

Feeding Cuphea oil to mice (two strains, 3 generations each) did not affect reproduction and had no adverse effect on parental animals. Animals were treated up to 12 months. Thus, Cuphea oil appears to be nontoxic, but was of no particular health benefit. (Hendrich et al. 1993).

The study is not comparable with current test guidelines. However, basic scientific principles are met and the results can be used to read across to nonanoic acid, which is closely related to decanoic acid and undergoes the same metabolism.

To this end, the decanoic acid dose was estimated to be 4700 mg/kg bw and day, which was the NOAEL in both strains of mice. This result can be read across to nonanoic acid.