Nonanoic acid

Endpoint summary

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Effects on fertility

Description of key information

Read across from octanoid and decanoic acid triglycerides provides sufficient information. Based on these data the NOAEL for nonanoic acid is considered to be in the range of 4500 mg/kg bw and day.

Link to relevant study records

Reference

Reference 1

Endpoint:

three-generation reproductive toxicity

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

Not the recommended number of animals. histopathology only on selected organs. No information on GLP status, limited investigation depth

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 416 (Two-Generation Reproduction Toxicity Study)

Deviations:

yes

Remarks:

3 generations; lower animal numbers; histopathology only on selected organs; No information on GLP status

GLP compliance:

not specified

Limit test:

yes

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: SASCO (Omaha, NE)
- Age at study initiation: (P) 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

Route of administration:

oral: feed

Vehicle:

other: basal diet

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): monthly
- Mixing appropriate amounts with (Type of food): basal diet with reduced beef tallow 886 g/kg instead of 172g/kg
- Storage temperature of food: 4°C

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 fatty 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

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

Positive control:

no

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
Animals fed for 5-12 months: : weeks 4, 13. 26, 39, and 45


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 food intake in grams is given.
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No.

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, pubs born/female

Offspring viability indices:

pubs at weaning/pups born

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Description (incidence and severity):

no consistent variation, but 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, but cuphea-fed mice had slightly lower body weights and lower feed intake

Food efficiency:

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Immunological findings:

not specified

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 proximal cortical tubules of all mice; spleen in some mice enlarged

Histopathological findings: neoplastic:

not specified

Other effects:

no effects observed

Description (incidence and severity):

Test substance intake: no consistent variations, but cuphea-fed mice had slightly lower body weights and lower feed intake

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Key result

Dose descriptor:

NOAEL

Effect level:

8.6 other: %

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Clinical signs:

not specified

Mortality:

not specified

Body weight and weight changes:

not specified

Food consumption and compound intake (if feeding study):

not specified

Food efficiency:

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

not specified

Neuropathological findings:

not specified

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Other effects:

no effects observed

Reproductive function: oestrous cycle:

not specified

Reproductive function: sperm measures:

not specified

Reproductive performance:

effects observed, treatment-related

Description (incidence and severity):

CBA/2 mice produced fewer offspring than females fed the basal diet.

Clinical signs:

not specified

Mortality / viability:

no mortality observed

Description (incidence and severity):

no effect in C57B1/6, in contrast to strain CBA/2 (strain-specific effect). Viability of pups from F1 and F2 parents reduced compared to those from F0 pups, but independent of the diet

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

10% reduced body weights in Cuphea fed C57B1/6 pups after 8 and 13 weeks. Reduced body weights in Cuphea fed CBA/2 pups after 13 weeks

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

18% reduced food intake in cuphea fed C57B1/6 mice after week 8. Reduced food intake in cuphea fed CBA/2 pups after 8 and 13 weeks.

Food efficiency:

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Sexual maturation:

no effects observed

Anogenital distance (AGD):

not specified

Nipple retention in male pups:

not specified

Organ weight findings including organ / body weight ratios:

no effects observed

Description (incidence and severity):

comparable between grouops; where statistically 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 mice enlarged

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

8.6 other: %

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

In C57B1/6 mice, body weights in Cuphea fed pups were decreased by 20% at four weeks of age.
Reduced body weights in Cuphea fed CBA/2 pups after 8 weeks.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Reduced food intake in Cuphea fed CBA/2 pups after 8 weeks

Behaviour (functional findings):

not specified

Developmental immunotoxicity:

not specified

Key result

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

ca. 8.6 other: %

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Reproductive effects observed:

not specified

Comments to histopathology in F0, 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.

 

 

 

 

 

 

 

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. The NOAEL according to this study is > 8.6% cuphea oil in feed.

Executive summary:

In this 3 generation feeding study two strains of mice (CBA/2 and C57B1/6) were fed a diet of 8.6% cuphea oil. 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. In the 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. Failureof mothers to succesfully nurture pups to weanling age (four weeks) was the only reproductive problem noted and affected the F1 and F2 mice of both diets, thus this is not related to cuphea oil. The F0 mice were exposed to a different diet and environment than were the F1 and F2 moce before breeding, but it is not clear how these differences might have led to the impairment of survival of pups in the later generations.

Animals were treated up to 12 months. Thus, Cuphea oil appears to be nontoxic, but was of no particular health benefit.

The study is not comparable with current test guidelines. However, basic scientific principles are met. According to this study, the NOAEL is 8.6% cuphea oil in both strains of mice.

Reference 2

Endpoint:

two-generation reproductive toxicity

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other:

Remarks:

the number of animals per dose or generation is not documented. No histopathological assessment of reproductive organs was performed. No statement regarding GLP status is available.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 416 (Two-Generation Reproduction Toxicity Study)

Version / remarks:

study predates guidelines

Deviations:

yes

Remarks:

). However, the number of animals per dose or generation is not documented. No histopathological assessment of reproductive organs was performed. No statement regarding GLP status is available.

GLP compliance:

no

Limit test:

yes

Species:

rat

Strain:

other: McCollum-Wisconsin

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: no data
- Age at study initiation: young adult

Housing: females: singly in plastic cages after mating

Route of administration:

oral: feed

Vehicle:

other: casein diet

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): no data
- Mixing appropriate amounts with (Type of food): casein diet containing 19.5% MCT and 2.5% safflower oil

Details on mating procedure:

no data

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

F0: 3 weks prior to mating until parturition
F1: in utero until day 163
F2: in utero until day 63

Frequency of treatment:

7 days/week

Dose / conc.:

19.5 other: %

No. of animals per sex per dose:

no data

Control animals:

yes

Details on study design:

The F0 (parental) generation were maintained on either of the thre diets: MCT, oleo oil and low fat for 3 weeks prior to mating.
The F1 generation was divided into three subgroups at 12 weeks of age. One subgroup was continued on the same diet, whereas the other two subgroups were swutch to the diets containing one of the other fats (nine experimental groups).

Positive control:

no

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: No data


DETAILED CLINICAL OBSERVATIONS: No data


BODY WEIGHT: No data


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 data
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No data

Oestrous cyclicity (parental animals):

no data

Sperm parameters (parental animals):

no data

Litter observations:

mean litter size; weight at birth and weight development until day 163 (F1) and day 63 (F2), respectively

Postmortem examinations (parental animals):

no data

Postmortem examinations (offspring):

weight development

Statistics:

no data

Reproductive indices:

no data

Offspring viability indices:

no data

Clinical signs:

not specified

Mortality:

mortality observed, non-treatment-related

Description (incidence):

For the parental generation, mortality during the lactation period was 6% for MCT, 7% for the oleo oil and 2% for the low fat diet.

Body weight and weight changes:

not specified

Food consumption and compound intake (if feeding study):

not specified

Food efficiency:

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Other effects:

not specified

Reproductive function: oestrous cycle:

not specified

Reproductive function: sperm measures:

not specified

Reproductive performance:

not specified

no data except that the mean litter size (9.0) was comparable to that of females fed oleo oil (9.1) or a low fat diet (9.6)

Dose descriptor:

NOAEL

Effect level:

19.5 other: %

Based on:

other:

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Clinical signs:

not specified

Mortality:

mortality observed, non-treatment-related

Description (incidence):

Mortality was relatively high in two of the groups receiving MCT: the one previously on MCT (22%) and the MCT group which previously had received the low dat diet (20%). In all other groups, mortality was 7% or less.

Body weight and weight changes:

not specified

Food consumption and compound intake (if feeding study):

not specified

Food efficiency:

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

not specified

Neuropathological findings:

not specified

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Other effects:

not specified

Reproductive function: oestrous cycle:

not specified

Reproductive function: sperm measures:

not specified

The different diets had no effect on litter size

Clinical signs:

not specified

Mortality / viability:

not specified

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not specified

Food efficiency:

not specified

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

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Sexual maturation:

not specified

Anogenital distance (AGD):

not specified

Nipple retention in male pups:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

not specified

Histopathological findings:

not specified

Other effects:

not specified

Behaviour (functional findings):

not specified

Developmental immunotoxicity:

not specified

body weight development of F1 and F2 pups was comparable to that of the oleo oil group, but higher than that of the low-fat group

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

19.5 other: %

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Clinical signs:

not specified

Dermal irritation (if dermal study):

not specified

Mortality / viability:

not specified

Body weight and weight changes:

not specified

Food consumption and compound intake (if feeding study):

not specified

Food efficiency:

not specified

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

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Sexual maturation:

not specified

Anogenital distance (AGD):

not specified

Nipple retention in male pups:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

not specified

Histopathological findings:

not specified

Other effects:

not specified

Behaviour (functional findings):

not specified

Developmental immunotoxicity:

not specified

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

19.5 other: %

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Reproductive effects observed:

not specified

Also reported in this study:

Fatty acid composition of breast milk was different from that in the diet which indicates that the dietary fatty acids were digested and newly synthesised before secretion into breast milk.

 

 

 

 

Conclusions:

The fertility of rats fed MCT was not affected in a 2-generation study. The study protocol is not comparable with current test guidelines. According to this study, the NOAEL for reproductive toxicity in > 19.5% MCT in diet.

Executive summary:

This is a pre-guideline and Pre-GLP study, the study protocol is therefore not comparable with current test guidelines, but it is similar to current 2 -Generation Reproductive Toxicity studies (OECD TG 416).

The fertility of rats fed MCT was not affected in this 2-generation study as evidenced by the mean litter size. The body weight of the F1 and F2 pups was recorded until day 163 and day 63 after parturition, respectively, and body weight development was not affected. The fatty acid composition of the milk from rats fed MCT or oleo oil did not reflect the fatty acid composition of the diets. Hence, the dietary fat was digested and milk fat was newly synthesised.

Based on the above it is concluded that the NOAEL of MCT is > 19.5% in diet.

Reference 3

Endpoint:

two-generation reproductive toxicity

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details on endpoint specific justification please see read-across report in section 13 or find a link in cross-reference “assessment report”.

Reason / purpose for cross-reference:

assessment report

Reason / purpose for cross-reference:

read-across source

Dose descriptor:

NOAEL

Effect level:

19.5 other: %

Based on:

test mat.

Remarks:

corresponds to ca. 8000 mg/kg bw/d nonanoic acid

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

19.5 other: %

Based on:

test mat.

Remarks:

corresponds to ca. 8000 mg/kg bw/d nonanoic acid

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

19.5 other: %

Based on:

test mat.

Remarks:

corresponds to ca. 8000 mg/kg bw/d nonanoic acid

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Reproductive effects observed:

not specified

Conclusions:

The fertility of rats fed MCT was not affected in a 2-generation study. The study protocol is not comparable with current test guidelines. According to this study, the NOAEL for reproductive toxicity in > 19.5% MCT in diet (corresponds to ca. 8000 mg/kg bw/d nonanoic acid).

Executive summary:

This is a pre-guideline and Pre-GLP study, the study protocol is therefore not comparable with current test guidelines, but it is similar to current 2 -Generation Reproductive Toxicity studies (OECD TG 416).

The fertility of rats fed MCT was not affected in this 2-generation study as evidenced by the mean litter size. The body weight of the F1 and F2 pups was recorded until day 163 and day 63 after parturition, respectively, and body weight development was not affected. The fatty acid composition of the milk from rats fed MCT or oleo oil did not reflect the fatty acid composition of the diets. Hence, the dietary fat was digested and milk fat was newly synthesised.

Based on the above it is concluded that the NOAEL of MCT is > 19.5% in diet (corresponds to ca. 8000 mg/kg bw/d nonanoic acid).

Reference 4

Endpoint:

three-generation reproductive toxicity

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details on endpoint specific justification please see read-across report in section 13 or find a link in cross-reference “assessment report”.

Reason / purpose for cross-reference:

assessment report

Reason / purpose for cross-reference:

read-across source

Key result

Dose descriptor:

NOAEL

Effect level:

8.6 other: %

Based on:

test mat.

Remarks:

corresponds to ca. 4500 mg/kg bw/d nonanoic acid

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

8.6 other: %

Based on:

test mat.

Remarks:

corresponds to ca. 4500 mg/kg bw/d nonanoic acid

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Dose descriptor:

NOAEL

Generation:

F2

Effect level:

ca. 8.6 other: %

Based on:

test mat.

Remarks:

corresponds to ca. 4500 mg/kg bw/d nonanoic acid

Sex:

male/female

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

Reproductive effects observed:

not specified

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. The NOAEL according to this study is > 8.6% cuphea oil in feed (corresponds to ca. 4500 mg/kg bw/d nonanoic acid).

Executive summary:

In this 3 generation feeding study two strains of mice (CBA/2 and C57B1/6) were fed a diet of 8.6% cuphea oil. 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. In the 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. Failureof mothers to succesfully nurture pups to weanling age (four weeks) was the only reproductive problem noted and affected the F1 and F2 mice of both diets, thus this is not related to cuphea oil. The F0 mice were exposed to a different diet and environment than were the F1 and F2 moce before breeding, but it is not clear how these differences might have led to the impairment of survival of pups in the later generations.

Animals were treated up to 12 months. Thus, Cuphea oil appears to be nontoxic, but was of no particular health benefit.

The study is not comparable with current test guidelines. However, basic scientific principles are met. According to this study, the NOAEL is 8.6% cuphea oil in both strains of mice (corresponds to ca. 4500 mg/kg bw/d nonanoic acid).

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

4 500 mg/kg bw/day

Study duration:

chronic

Species:

rat

Quality of whole database:

Sufficient for assessment

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

 

Information from supporting substances has been used to fulfil the informationrequirementsfor this endpoint.For read across justification, see the attached file in endpoint 13 ( Analogue approach justification):

 

Nonanoic acid is not considered to affect fertility at dose levels up to 4700 mg/kg bw and day in rats. No fertility study on nonanoic acid itself was located, but this result was obtained from a read across approach from studies where rats were fed triglycerides (MCT) containing octanoic and decanoic acid. These acids are completely absorbed and metabolised after hydrolysis of the triglycerides. Nonanoic acid is closely related to these acids and undergoes the same metabolism, which justifies cross reading. For clarity, summaries of the two available studies are given below.

It should be mentioned that it was stated in the CLH report for nonanoic acid that the available information and human fatty acid exposure information is sufficient to conclude that dietary fatty acids do not pose a risk for fertility, and that therefore no further studies are required. There is no contradictory information in the ECHA RAC report on nonanoic acid.

 

Waiving Reprotox screening

 

According to Annex VIII, section 8.7.1, column 2, No reproductive/devlopemental toxicity screening study is required if a pre-natal developmental toxicity study (Annex IX, 8.7.2) or, either an Extended One-Generation Reproductive Toxicity Study (B.56, OECD TG 443) (Annex IX, Section 8.7.3) or a two-generation study (B.35, OECD TG 416), is available.

 

Harkins, 1968: The fertility of rats fed MCT containing 75% octanoic acid and 25% decanoic acid was not affected in a 2-generation study as evidenced by the mean litter size. The body weight of the F1 and F2 pups was recorded until day 163 and day 63 after parturition, respectively, and body weight development was not affected. The fatty acid composition of the milk from rats fed MCT or oleo oil did not reflect the fatty acid composition of the diets. Hence, the dietary fat was digested and milk fat was newly synthesised (Harkins et al. 1968).

This is a pre-guideline and Pre-GLP study, the study protocol is therefore not comparable with current test guidelines. However, there was no indication of adverse effects on fertility even at very high doses. The combined NOAEL of octanoic and decanoic acid was apparently >8000 mg/kg bw and day which can be used for the assessment of nonanoic acid in a read-across approach. The latter was also acknowledged in the CLH proposal for nonanoic acid (Austria, 2012) and in the Opinion of the ECHA Risk Assessment Committee for nonanoic acid (2013).

 

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 octanoic and decanoic acid dose was estimated to be 4500 mg/kg bw and day, which was the NOAEL in both strains of mice. This result can be read across to nonanoic acid.

 

Effects on developmental toxicity

Description of key information

No adverse effects in dams or offspring at a limit dose of 1500 mg nonanoic acid/kg bw/day (Celanese/Hazleton, 1983, RL2).  No substance related developmental toxicity observed in rabbits with the read-across substance MCT (Henwood, 1997). 

 

Link to relevant study records

Reference

Reference 1

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 May 1982 to 24 June 1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

: minor deviations and some deficiencies in data reporting

GLP compliance:

not specified

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories Inc. New York
- Age at study initiation: about 14 weeks
- Weight at study initiation: 230.5 +/-17.9 g
- Housing: individually, 2 females per male during mating
- Diet (ad libitum): Purina Rodent Laboratory chow
- Water (ad libitum): tap water
- Acclimation period: about 9 weeks


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 24.4 +/- 0.5
- Humidity (%): 57 +/- 4.8
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
The amount of compound required was weighed and diluted with vehicle, dosing was performed from stirred dilutions

Analytical verification of doses or concentrations:

no

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: 1/2
- Length of cohabitation: maximum of three weeks
- Verification of same strain and source of both sexes: yes
- Proof of pregnancy: vaginal plug or sperm in vaginal smear referred to as day 0 of pregnancy

Duration of treatment / exposure:

gd 6 - 15

Frequency of treatment:

1x/d

Duration of test:

9 days

Remarks:

Doses / Concentrations:
1500 mg/kg bw/day in corn oil
Basis:
nominal conc.

No. of animals per sex per dose:

22

Control animals:

yes, concurrent vehicle

Details on study design:

Administered dose was based on individual body weights from the most recent weighing interval and approximately the same time each day.

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: once daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once daily

BODY WEIGHT: Yes
- Time schedule for examinations: on days 0, 6, 9, 12, 15 and 50 of gestation

FOOD AND WATER CONSUMPTION. Yes
- Time schedule for examinations: on days 6-8, 9-11, 12-14, 15-17, 18-20

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 20
- Organs examined: gross examination of all internal organs, detailed examination of ovaries (see below)

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: Yes
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes

Fetal examinations:

- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: about one-third per litter
- Skeletal examinations: Yes: about two-third per litter
- Head examinations: Yes: [all per litter / half per litter / #? per litter ] / No / No data
- Body weights and crown-rump distance: Yes

Statistics:

The following statistic tools were used:
National Cancer Institute Package; Box's test for homogeneity of variance, followed by one-way ANOVA and Dunnett's T-test; test of multiple proportions; Fisher's exact test

Indices:

Mean incidence of visceral anomalies: group mean of [(number fo fetuses with anomalies per litter/number of fetuses examined viscerally per litter) x 100]
Mean incidence of visceral variants: group mean of [(number fo fetuses with variants per litter/number of fetuses examined viscerally per litter) x 100]
Mean incidence of skeletal anomalies: group mean of [(number fo fetuses with anomalies per litter/number of fetuses examined viscerally per litter) x 100]
Mean incidence of skeletal variants: group mean of [(number fo fetuses with variants per litter/number of fetuses examined viscerally per litter) x 100]

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
There were no compound-related maternal effects (body weight gain, food and water consumption, gross pathology).

Key result

Dose descriptor:

NOAEL

Effect level:

1 500 mg/kg bw/day

Basis for effect level:

other: maternal toxicity

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
Skeletal variants and delayed ossification (both 38.2%) were identical to the values of the control group (38.2%). No statistically significant compound-related skeletal anomalies were noted: Of a selection of 80 fetuses from 22 litters, there were two instances of cleft palate, two with small tongue, and a single incidence of hydroureter that were not seen in control fetuses.

Key result

Dose descriptor:

NOAEL

Effect level:

1 500 mg/kg bw/day

Basis for effect level:

other: teratogenicity

Key result

Dose descriptor:

NOAEL

Effect level:

1 500 mg/kg bw/day

Basis for effect level:

other: fetotoxicity

Abnormalities:

not specified

Developmental effects observed:

not specified

Summarised results (maternal body weights, ovarian, uterine and litter data, fetal examinations) are presented in the attached document.

Conclusions:

Under the conditions of this developmental study there were no effects with respect to dams or offspring.

Executive summary:

22 female Sprague-Dawley rats were treated orally by gavage with 1500 mg/kg bw/day of the test item on days 6 -15 of gestation in a developmental toxicity test. The 22 control animals received the vehicle corn oil. After the sacrifice at day 20 of gestation no adverse effects could be observed in the exposed dams. There were no differences between the offspring of treated and control rats with respect to teratogenic or fetotoxic effects (resorptions, viability, fetal weights, skeletal or visceral malformations or variations). Therefore the NOAEL of this study is 1500 mg/kg bw/day for dams and offspring (Celanese/Hazleton, 1983).

Reference 2

Endpoint:

developmental toxicity

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

For details on endpoint specific justification please see read-across report in section 13 or find a link in cross-reference “assessment report”.

Reason / purpose for cross-reference:

assessment report

Reason / purpose for cross-reference:

read-across source

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Remarks:

corresponds to ca. 830 mg/kg bw/d nonanoic acid

Basis for effect level:

other: maternal toxicity

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Remarks:

corresponds to ca. 830 mg/kg bw/d nonanoic acid

Basis for effect level:

other: teratogenicity

Abnormalities:

not specified

Developmental effects observed:

not specified

 

 

 

Conclusions:

Intravenous doses of MCT (up to 4280 mg/kg bw and day, GD 7-19) caused maternal effects at the high dose as well as effects on fetuses. The NOAEL was therefore 1000 mg/kg bw and day (corresponds to ca. 830 mg/kg bw/d nonanoic acid) for maternal toxicity and for developmental toxicity.

Executive summary:

The study used as source investigated devlopmental toxicity in rabbits. The study results of the source compound were considered applicable to the target compound and were used for classification and labelling acc. to REGULATION (EC) No 1272/2008. Justification and applicability of the read-across approach (structural analogue) is outlined in the read-across report in section 13 or find a link in cross reference “assessment report”.

Reference 3

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other:

Remarks:

No information on GLP, only 2 doses (but exceeding limit dose)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

2 doses tested, no information of GLP

GLP compliance:

not specified

Limit test:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: HRP Inc, Denver, PA, USA
- Age at study initiation: 5.5 to 6.5 months
- Weight at study initiation: 330 to 4446 g on GD 0
- Housing: singly
- Diet: ad libitum except during dose administration
- Water: ad libitum except during dose administration
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
air-conditioned rooms

Route of administration:

other: intravenous infusion (ear vein)

Vehicle:

soya oil

Details on exposure:

- Route: intravenous injection, caudal vein
- Dose volumes: 5 and 21.4 mL/kg bw
- Duration: 4 hours

VEHICLE
- Justification for use and choice of vehicle (if other than water): for reasons of solubility
- Concentration in vehicle: 3.1 ratio of MCT:LCT from soya oil

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Stability was analytically determined which implies analytical verification of composition and doses. Methods were not described.

Details on mating procedure:

Time-mated animals; no further details described.

Duration of treatment / exposure:

GD 7 through 19

Frequency of treatment:

daily, 5h/day

Duration of test:

until GD 29

Dose / conc.:

1 000 mg/kg bw/day (nominal)

Remarks:

i.v. dosing

Dose / conc.:

4 280 mg/kg bw/day (nominal)

Remarks:

i.v. dosing

No. of animals per sex per dose:

15

Control animals:

yes, sham-exposed

Details on study design:

- Dose selection rationale: 4280 mg/kg bw/day was the highest dose in preclinical studies that did not produce narcosis

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: at least daily

BODY WEIGHT: Yes
- Time schedule for examinations: pre-dose and on GD5 through GD20

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 29

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: Yes
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes

Fetal examinations:

- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: half per litter
- Skeletal examinations: Yes: half per litter
- Head examinations: Yes

Statistics:

The litter was the experimental unit for evaluation and all comparisons were made with the control group. Amongst other calculations, ANOVA followed by Dunnett's test was used to analyse body weights, feed consumption, caesarian section data. Foetal abnormality data were analysed using the Cochran.-Armitage test and the Fisher-Irwin exact test.

Clinical signs:

no effects observed

Mortality:

mortality observed, non-treatment-related

Description (incidence):

One animal in the control group died on GD11 and one animal in the high dose group was sacrificed aftr aborting on GD20. Decreased feed consumption, resulting in a decline in the health of this animal, may have contributed to the abortion. The abortion was not considered to be test article-related as it was in the range of historical control incidence. There were no remarkable necropsy findings for either animal.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

body weight changes were significantly lower for the 4.28 g lipid/kg group during the dosing interval (GD 7 to 20)

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

feed consumption was significantly lower for the 4.28 g lipid/kg group during the dosing interval (GD 7 to 20). Feed consumption continued to be significantly lower for this group during the early posttreatment period (GD 20 to 24), but recovery was noted at a later interval (GD 24 to 29).

Food efficiency:

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

not specified

Neuropathological findings:

not specified

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Other effects:

no effects observed

Number of abortions:

effects observed, non-treatment-related

Description (incidence and severity):

see above

Pre- and post-implantation loss:

no effects observed

Total litter losses by resorption:

no effects observed

Early or late resorptions:

no effects observed

Dead fetuses:

no effects observed

Changes in pregnancy duration:

not specified

Changes in number of pregnant:

no effects observed

Details on maternal toxic effects:

Maternal toxic effects:yes

Details on maternal toxic effects:
All low-dose animals survived whereas one control and one high-dose rabbit were sacrificed after aborting on GD 20; the treated animal had the lowest feed consumption in the group. The abortion was inside the historical control range and there were no remarkable necropsy findings for either animal.
The only clinical sign noted was that 3/15 animals had no fecal output for 1 day during the treatment period. Body weights were comparable, but feed consumption and body weight gain were significantly reduced (p<0.01) during the treatment period (GD 12 through GD20) and also in the recovery period thereafter (until GD 29). Reduced feed consumption was expected due to the high caloric nature of the test material.

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Fetal body weight changes:

not examined

Reduction in number of live offspring:

no effects observed

Changes in sex ratio:

no effects observed

Changes in litter size and weights:

no effects observed

Changes in postnatal survival:

no effects observed

External malformations:

no effects observed

Description (incidence and severity):

The incidence of external malformations was increased at the high dose

Skeletal malformations:

effects observed, treatment-related

Description (incidence and severity):

skeletal findings were increased in the low dose group without gaining a level of significance. The incidence skeletal malformations was increased at the high dose.

Visceral malformations:

effects observed, non-treatment-related

Description (incidence and severity):

The total incidence of litters in the 1 g lipid/kg group with fetuses having soft tissue abnormalities was significantly higher than that of the control group however, no significant differences were present when individual malformations and variations were analyzed statistically. Although the incidence of litters in the 4.28 g lipid/kg group with viscerally abnormal fetuses was also higher than controls, the difference was not statistically significant.

In general, soft tissue abnormalities were present in the test article treated groups as single fetal or litter incidences restricted to three or four litters/group, suggesting a litter-related oc- currence. Because no soft tissue abnormalities (with the exception of absent azygous lobe of the lung) were noted for the control litters, the relationship of the abnormalities in the test article groups to the test article is inconclusive.

Details on embryotoxic / teratogenic effects:

Details on embryotoxic / teratogenic effects:
At the low dose (1000 mg/kg bw and day) foetal postimplantation was slightly increased and the mean body weight was slightly reduced without gaining a level of significance This was, however, the case at the high dose where early and late resorptions were clearly increased; as a consequence, the number of live foetuses was decreased (p<0.01), and the mean foetal weight was significantly decreased (p<0.01). The incidence of external, soft tissue and skeletal malformations was increased at the high dose (statistically significant).

Key result

Dose descriptor:

NOAEL

Effect level:

ca. 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Basis for effect level:

other: teratogenicity

Abnormalities:

not specified

Developmental effects observed:

not specified

 

 

 

Conclusions:

Intravenous doses of MCT (up to 4280 mg/kg bw and day, GD 7-19) caused maternal effects at the high dose as well as effects on fetuses. The NOAEL was therefore 1000 mg/kg bw and day for maternal toxicity and for developmental toxicity.

Executive summary:

Time-mated rabbits (15/group) received intravenous infusions into the ear vein (duration 5 h/day) during Gestation Days 7 through 19 of a 20% lipid emulsion that contained a ratio of 3:1 of MCT and Long Chain Triglycerides (LCT) from soy bean oil at doses of 1 and 4.28 g/kg bw and day. Controls received 0.9% saline. Medium chain fatty acids are 6 to 12 carbons in length. The 20% lipid emulsion is composed primarily of 8- and 10-carbon fatty acids, with only traces of 6- and 12-carbon fatty acids. The does were observed for clinical signs and sacrificed at termination, the does and of the uterus content were examined.

No treatment-related mortalities were noted. The only clinical sign was a reduced faecal output of 3/15 does on one day. Body weight change and feed intake was significantly reduced (p<0.01) in high-dose rabbits which was expected because of the high caloric test material. No adverse effect was noted in does at 1000 mg/kg bw and day, hence this was considered to represent the maternal NOAEL value.

 

Foetal findings: at the low dose (1000 mg/kg bw and day) foetal postimplantation loss was slightly increased and the mean foetal weight was slightly reduced without gaining a level of significance. This was, however, the case at the high dose where early and late resorptions were clearly increased; consequently, the number of live foetuses was decreased (p<0.01), and the mean foetal weight was significantly decreased (p<0.01). The incidence of external (p<0.05), soft tissue and skeletal malformations (p<0.05) was increased at the high dose.

The incidence of soft tissue findings was also increased in low dose foetuses, but without gaining a level of significance when individual malformations were analysed statistically. Similarly, an increase of skeletal findings was seen in the low dose group below a level of significance. Based on these findings the NOAEL for developmental toxicity was set at 1000 mg/kg bw and day, and the authors assume that the findings at 4280 mg/kg bw and day are attributable to the low feed consumption and malnutrition rather than a direct teratogenic effect of the test material (Henwood et al. 1997).

The study is considered to be valid. The intravenous route was used because the parenteral route is used in patients that cannot meet their nutritional needs by the conventional oral route, and 1000 mg/kg bw and day is the approximate clinical dose, whereas 4280 mg/kg bw and day is reportedly the highest preclinical dose that did not cause narcosis.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 500 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

Sufficient for assessment; meets information requirements

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Additional information

Information from supporting substances has been used to fulfil the information requirements for this endpoint. For read across justification, see the atteched file in endpoint 13 ( Analogue approach justification):

 

Overall

Information requirements are fulfilled for this endpoint. The NOAEL for developmental toxicity was 1500 mg nonanoic acid in the rat (Celanese, 1983; highest dose tested) which is in good agreement with observations from a rat study using MCT (Henwood et al. 1997; MCT = Medium Chain Triglycerides; contain mainly C8 and C10 acid from which read across to nonanoic acid can be made). No developmental toxicity was observed in rats up to 4820 mg MCT/kg bw/d (corresponds to ca. 4000 mg nonanoic acid).

MCT was also tested in the rabbit (Henwood et al. 1997). Developmental effects were seen at the high dose only where the does showed clear maternal toxic effects (significantly reduced feed intake and reduced body weight gain p>0.01). Developmental toxicity was considered to result from the low feed intake and malnutrition of the does. The NOAEL for nonanoic acid that was derived from this study was therefore 830 mg/kg bw and day. This value was not considered for the derivation of a DNEL because the toxic effects were secondary to the low maternal feed intake, rather than to direct toxic effects and the height of the NOAEL was mainly due to the spacing of the dose groups.

The studies outlined above fulfil the information requirements for the endpoint Developmental Toxicity.

For clarity, the executive summaries of all available studies are presented below.

 

1- In this reliable developmental toxicity study 22 female Sprague-Dawley rats were treated orally by gavage with 1500 mg/kg bw/day of the test item on days 6 -15 of gestation. The 22 control animals received the vehicle corn oil. After the sacrifice at day 20 of gestation no adverse effects could be observed in the exposed dams. There were no differences between the offspring of treated and control rats with respect to teratogenic or foetotoxic effects (resorptions, viability, foetal weights, skeletal or visceral malformations or variations). Therefore the NOAEL of this study is 1500 mg/kg bw/day for dams and offspring (Celanese/Hazleton, 1983). This study was performed similar to OECD guideline 414, judged to be reliable and selected as key study (Celanese, 1983)

 

2 -Time-mated rats (25/group) received intravenous infusions into the caudal vein (duration 4h/day) during gestation Days 6 through 15 of a 20% lipid emulsion that contained a ratio of 3:1 of MCT and Long Chain Triglycerides (LCT) from soy bean oil at doses of 1 and 4.28 g/kg bw and day. Controls received 0.9% saline). Medium chain fatty acids are 6 to 12 carbons in length. The 20% lipid emulsion is composed primarily of 8- and 10-carbon fatty acids, with traces of 6- and 12-carbon fatty acids. The dams were observed for clinical signs and sacrificed at termination. Examinations of the dams and of the uterus content were performed.

 

No clinical signs or mortalities were noted. Changes in high-dose rats (enlarged lymph nodes, spleen, and renal pelvis; small thymus, small red lung foci) were considered to be related to treatment, hence the NOAEL was 1 000 mg/kg bw and day for maternal toxicity (corresponds to ca. 830 mg/kg bw/d nonanoic acid). As to the foetuses, there were no significant differences compared to controls regarding early or late resorptions, post implantation loss, dead or alive foetuses, mean uterine weight and foetal weight (though there was a trend towards lower weights at the high dose), and there were no external, soft tissue or skeletal changes that could be related to treatment. Hence, the NOAEL for developmental toxicity and teratogenicity was 4280 mg/kg bw and day (corresponds to ca, 4000 mg/kg bw/d nonanoic acid) (Henwood et al., 1997).

 

The study is considered to be valid. The intravenous route was used because the parenteral route is used in patients that cannot meet their nutritional needs by the conventional oral route, and 1000 mg/kg bw and day is the approximate clinical dose, whereas 4280 mg/kg bw and day is reportedly the highest preclinical dose that did not cause narcosis.

 

3- Time-mated rabbits (15/group) received intravenous infusions into the ear vein (duration 5 h/day) during Gestation Days 7 through 19 of a 20% lipid emulsion that contained a ratio of 3:1 of MCT and Long Chain Triglycerides (LCT) from soy bean oil at doses of 1 and 4.28 g/kg bw and day. Controls received 0.9% saline. Medium chain fatty acids are 6 to 12 carbons in length. The 20% lipid emulsion is composed primarily of 8- and 10-carbon fatty acids, with only traces of 6- and 12-carbon fatty acids. The does were observed for clinical signs and sacrificed at termination, the does and of the uterus content were examined.

No treatment-related mortalities were noted. The only clinical sign was a reduced faecal output of 3/15 does on one day. Body weight change and feed intake was significantly reduced (p<0.01) in high-dose rabbits which was expected because of the high caloric test material. No adverse effect was noted in does at 1000 mg/kg bw and day, hence this was considered to represent the maternal NOAEL value.

 

Foetal findings: at the low dose (1000 mg/kg bw and day) foetal postimplantation loss was slightly increased and the mean foetal weight was slightly reduced without gaining a level of significance. This was, however, the case at the high dose where early and late resorptions were clearly increased; consequently, the number of live foetuses was decreased (p<0.01), and the mean foetal weight was significantly decreased (p<0.01). The incidence of external (p<0.05), soft tissue and skeletal malformations (p<0.05) was increased at the high dose.

The incidence of soft tissue findings was also increased in low dose foetuses, but without gaining a level of significance when individual malformations were analysed statistically. Similarly, an increase of skeletal findings was seen in the low dose group below a level of significance. Based on these findings the NOAEL for developmental toxicity was set at 1000 mg/kg bw and day, and the authors assume that the findings at 4280 mg/kg bw and day are attributable to the low feed consumption and malnutrition rather than a direct teratogenic effect of the test material (Henwood et al. 1997). This interpretation is supported by Cappon et al. (2005; "Effects of feed restriction during organogenesis on embryo-fetal development in rabbit." Birth Defects Research. Part B: Developmental and Reproductive Toxicology 74(5): 424-430.) who concluded "that feed restriction to feed levels that produce substantial reductions in maternal body weight gain can result in developmental toxicity expressed by abortion, reduced fetal weight, and alterations in ossification". Therefore, the findings in rabbits are not regarded as relevant for a possible classification. 

 

The study is considered to be valid. The intravenous route was used because the parenteral route is used in patients that cannot meet their nutritional needs by the conventional oral route, and 1000 mg/kg bw and day is the approximate clinical dose (corresponding to ca. 830 mg/kg bw/d nonanoic acid), whereas 4280 mg/kg bw and day (corresponding to ca. 4000 mg/kg bw/d nonanoic acid) is reportedly the highest preclinical dose that did not cause narcosis.

 

 4- According to the CLH report, the NOAEL of nonanoic acid was 1500 mg/kg bw and day for both maternal and developmental toxicity in a valid developmental study using rats. It may also be acknowledged that a developmental toxicity study with Nonanoic acid was submitted in the context of the BPD 98/8/EC Annex I inclusion procedure. The study is owned by the respective applicant W. Neudorff GmbH KG and the data are protected. However since the data requirement for the evaluation of developmental toxicity is fulfilled with the references provided above and the study is not used to the advantage of the applicant of Decanoic and Octanoic acid (Fatty Acid Consortium) it may be cited and discussed also for the evaluation of Decanoic acid and Octanoic acid (Austria, 2012: CLH reports for Octanoic and Decanoic acid, respectively, section 4.11.3).

 

The Competent Authority further argued that animals and humans are exposed to fatty acids via food feed, that fatty acids are rapidly and completely metabolised to carbon dioxide and water, that no bioaccumulation has to be considered, and that no adverse effects were seen in repeated dose studies even at high doses of MCT, and that no adverse effects of fatty acid ingestion on reproduction is known. Based on this it was concluded that no further developmental toxicity study would be required (Austria 2011; section 4.11). EFSA (2013) argued likewise that no new studies are necessary on this endpoint. See also assessment reports included in Section 13.

 

 

Mode of Action Analysis / Human Relevance Framework

In the absence of information on a species specific effect the data are regarded as relevant for humans.

Justification for classification or non-classification

Based on the available information a classification of the test substance is not required according to Regulation (EC) No 1272/2008.