Farnesol

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

The key information supporting the evaluation of reproductive toxicity of the test item is a regulatory subchronic repeated dose toxicity study with reproductive toxicity screen by oral administration of the read-across substance, Nerolidol, in rats, conducted according to OECD 422 and GLP. In this study, the No Observed Adverse Effect Levels (NOAELs) for fertility and reproduction were established following repeated daily treatment to the parent animals and NOAELs were also established for developmental toxicity to F1 offspring based on the limited data available in this screening study.Read-across is appropriate as the test substance and nerolidol are very similar in chemical structure, differing only by the interchange of a hydroxyl group and double bond on carbon positions 1 and 2, and very similar in physico-chemical properties.The oral and dermal acute and repeat dose toxicity data show that the toxicity of farnesol and nerolidol are similar in order of magnitude when comparing dose levels expressed in terms of mg/kg bodyweight.Given the similarities in chemical and biological effects, nerolidol is considered to be a suitable read-across substance.

Link to relevant study records

Reference

Reference 1

Endpoint:

screening for reproductive / developmental toxicity

Remarks:

based on generations indicated in Effect levels

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The read-across hypothesis is based on different compounds with qualitatively similar properties using the analogue approach, following Scenario 2 of the Read-Across Assessment Framework (ECHA 2017).

2. SOURCE AND TARGET CHEMICAL(S)
Target substance: Farnesol (CAS: 4602-84-0; EC: 225-004-1)
Source substance: Nerolidol (CAS: 7212-44-4; EC: 230-597-5)

3. ANALOGUE APPROACH JUSTIFICATION
For the prediction of human health endpoints, similar qualitative effects were observed in the acute dermal toxicity study and repeat dose oral toxicity study for farnesol and nerolidol. Limited information is available to assess the reproduction / developmental toxicity of farnesol, however given the similarities in toxicokinetic profile as demonstrated in other toxicity studies, no difference in effects from the source substance are predicted. Both the target and source substances undergo a similar metabolic pathway. The bioavailability of nerolidol may be greater than farnesol (as observed experimentally), therefore read-across from nerolidol may represent a worst-case approach.

4. DATA MATRIX
See "Read-across justification" in Section 13.2.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3650 (Combined Repeated Dose Toxicity Study With the Reproduction/Developmental Toxicity Screening Test)

Vehicle:

unchanged (no vehicle)

Duration of treatment / exposure:

In total, females were treated for 57 days and males treated for 36 days

Frequency of treatment:

Treated animals were fed ad libitum

Clinical signs:

no effects observed

Dermal irritation (if dermal study):

not examined

Mortality:

not specified

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Reduced body weight gain and food consumption male and females treated at 12000 ppm

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Reduced body weight gain and food consumption male and females treated at 12000 ppm

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

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Minimal central hepatocellular hypertrophy in females treated at 12000 ppm and minimal fatty change in females treated at 12000 and 4000 ppm

Histopathological findings: neoplastic:

not specified

Other effects:

no effects observed

Reproductive function: oestrous cycle:

not specified

Reproductive function: sperm measures:

no effects observed

Reproductive performance:

no effects observed

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
There were no clinical signs of ill health or reaction to treatment observed at 12000, 4000or 1500 ppm and there were no treatment related mortalities among the F0 parent animals.

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS)
Decreased body weight gain in males weeks 0-1 treated at 12000 ppm (45% below controls); Decreased body weight gain in females treated at 12000 ppm in weeks 0-1 (73% below controls), gestation period (37% below controls) and during lactation (40 % below controls).
Reduced food intake in males treated at 12000 ppm in weeks 0-2 (10-18% below controls); Reduced food intake in females treated at 12000 ppm in weeks 0-1 (25% below controls), gestation period (20% below controls) and post natal days 1-4 (32% below controls).

TEST SUBSTANCE INTAKE (PARENTAL ANIMALS)
The dietary inclusion levels of 1500, 4000 and 12000 ppm correspond to 102, 266 and 758 mg/kg/day in males; 105, 279 and 705 mg/kg/day in non-pregnant females; 120, 340 and 824 mg/kg/day in pregnant females; 193, 468 and 1194 mg/kg/day in lactating females.

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS)
There were no effects reported on estrous cycle of femal rats during the routine clinical observations.

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS)
There were no effects observed on the pathological assessment of the male reproductive tract that were indicative of any effects on sperm production.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
In males the mating index was 100% in all groups including controls. Fertility was proven for most of the F0 parental males within the scheduled mating interval for the F1 litter with the male fertility index ranging between 90% and 100% without showing any relation to dose level.
In females the mating index for the F1 litter was 100% in all groups. The fertility index varied between 90% in females treated at 1500 or 12000 ppm and 100% in control females and those treated at 4000 ppm. The mean duration of gestation was similar in all groups (i.e. between 21.6 and 21.9 days) and the gestation index was 100% in all groups. Implantation, prenatal development and delivery were not affected by the treatment since neither the mean number of implantation sites nor the postimplantation loss or the average litter size showed any statistically significant differences between the groups.

ORGAN WEIGHTS (PARENTAL ANIMALS)
Statistically significant absolute and relative increased liver weights in males and females treated at 12000 ppm and also in females treated at 4000 ppm.

GROSS PATHOLOGY (PARENTAL ANIMALS)
The liver was discoloured in males and females treated at 12000 ppm, however, this finding is not considered to be adverse.

HISTOPATHOLOGY (PARENTAL ANIMALS)
Minimal or slight central hepatocellular hypertrophy was observed in females treated at 12000 ppm. In addition a minimal fatty change was noted in females treated at 12000 or 4000 ppm.

Key result

Dose descriptor:

NOAEL

Effect level:

> 266 mg/kg bw/day

Based on:

test mat.

Sex:

male

Basis for effect level:

body weight and weight gain

food consumption and compound intake

organ weights and organ / body weight ratios

gross pathology

Key result

Dose descriptor:

NOAEL

Effect level:

> 105 mg/kg bw/day

Based on:

test mat.

Sex:

female

Basis for effect level:

body weight and weight gain

food consumption and compound intake

organ weights and organ / body weight ratios

gross pathology

histopathology: non-neoplastic

Key result

Dose descriptor:

NOAEL

Effect level:

> 758 mg/kg bw/day

Based on:

test mat.

Sex:

male

Basis for effect level:

reproductive function (sperm measures)

reproductive performance

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Dose descriptor:

NOAEL

Effect level:

> 705 mg/kg bw/day

Based on:

test mat.

Sex:

female

Basis for effect level:

reproductive performance

Remarks on result:

not determinable due to absence of adverse toxic effects

Clinical signs:

not examined

Dermal irritation (if dermal study):

not examined

Mortality:

not examined

Body weight and weight changes:

not examined

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not examined

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

not examined

Clinical signs:

no effects observed

Dermal irritation (if dermal study):

not examined

Mortality / viability:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Lower body weight gain in pups of the 12000 ppm group days PND1-4

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 examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Other effects:

not specified

Behaviour (functional findings):

not specified

Developmental immunotoxicity:

not specified

VIABILITY (OFFSPRING)
The rate of liveborn pups was not affected by the test substance as indicated by live birth indices of 100% in all groups. The viability index indicating pup mortality during lactation (PND 0-4) varied between 98% in the 1500 ppm group and 100% in all other groups. The sex distribution and sex ratios of live F1 pups on the day of birth and PND4 did not show any significant differences between control and treated groups.

CLINICAL SIGNS (OFFSPRING)
There were no test substance-related adverse clinical signs observed in any of the F1 pups.

BODY WEIGHT (OFFSPRING)
Mean body weights of the high-dose pups (12000 ppm) were statistically significantly below control on PND 4 (about 13% below control). Body weight gain for PND 1-4 was statistically significantly decreased in the high-dose F1 pups (about 38% below control).

SEXUAL MATURATION (OFFSPRING)
Not examined

ORGAN WEIGHTS (OFFSPRING)
Not examined

GROSS PATHOLOGY (OFFSPRING)
No findings were observed at gross necropsy in all F1 pups

HISTOPATHOLOGY (OFFSPRING)
Not examined

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

ca. 340 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Based on slightly reduced growth and development of offspring, secondary to maternal toxicity at the 4000 ppm treatment level

Clinical signs:

not examined

Dermal irritation (if dermal study):

not examined

Mortality / viability:

not examined

Body weight and weight changes:

not examined

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not examined

Histopathological findings:

not examined

Other effects:

not examined

Behaviour (functional findings):

not examined

Developmental immunotoxicity:

not examined

Key result

Reproductive effects observed:

no

From dietary inclusion levels of 1500, 4000 and 12000 ppm, the test substance intake in terms of mg/kg/day was calculated as follows:

Males - 102, 266 and 758 mg/kg/day

Non-pregnant females - 105, 279 and 705 mg/kg/day

Pregnant females - 120, 340 and 824 mg/kg/day

Lactating females - 193, 468 and 1194 mg/kg/day

Conclusions:

Under the conditions of this reproduction/developmental toxicity screening test the NOAEL (no observed adverse effect level) for reproductive performance and fertility was considered to be 12000 ppm for the F0 parental rats. The NOAEL for developmental toxicity in the F1 progeny of the test substance treated groups was found to be 4000 ppm toxicity based on slightly reduced growth and development of offspring, secondary to maternal toxicity.

Executive summary:

Under the conditions of this Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test in Wistar Rats treatment with Nerolidol showed general systemic toxicity in the F0 males at 12000 ppm (equivalent to 758 mg/kg/day) and in the F0 females at 12000 ppm (equivalent to 705 to 1194 mg/kg/day) and 4000 ppm (equivalent to 279 to 468 mg/kg/day). These effects were manifest as reductions in food intake and body weight gain and increased liver weights with associated histopathological hepatocellular changes including hypertrophy and fatty change. However, there were no reproductive toxicological effects seen in either males or females at the dose levels associated with systemic toxicity. The only sign of developmental toxicity was a slight reduction of offspring body weights/body weight gain at the high dose level of 12000 ppm. This was considered by the authors to be indicative of a temporary developmental delay secondary to the impaired wellbeing of the dams in this treatment group so the NOAEL for reproduction and fertility in the F0 rats was considered to be 12000 ppm (equivalent to 758 mg/kg/day for males and 705 mg/kg/day for females). This study is considered to be reliable without restriction (Klimisch 1) as it was GLP-compliant and was conducted according to OECD 422 and OPPTS 870.3650. This data may be used as key data, as nerolidol is a suitable read-across source to the target substance based on similar chemical structure and hazard data.

Reference 2

Endpoint:

screening for reproductive / developmental toxicity

Remarks:

based on generations indicated in Effect levels

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Version / remarks:

1996

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3650 (Combined Repeated Dose Toxicity Study With the Reproduction/Developmental Toxicity Screening Test)

Version / remarks:

2000

Deviations:

no

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 10-12 weeks
- Weight at study initiation: Males 279.3-311.0g; Females 182.8-218.0g
- Housing: Individually housed in Makrolon type M III cages; pregnant females were provided with nesting material (Cellulose wadding); for enrichment wooden gnawing blocks were added to the cages.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24oC
- Humidity (%): 30-70%
- Air changes (per hr): 15/hour
- Photoperiod (hrs dark / hrs light): 12 hours dark/12 hours light
Details on oral exposure:
DIET PREPARATION
- Rate of preparation of diet (frequency): Test diets were prepared four times during the study. The maximum period for which each test diet was fed was less than 48 days.
- Mixing appropriate amounts with (Type of food): Kliba maintenance diet mouse/rat "GLP" meal
- Storage temperature of food: Not stated

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): Test diets were prepared four times during the study. The maximum period for which each test diet was fed was less than 48 days.
- Mixing appropriate amounts with (Type of food): Kliba maintenance diet mouse/rat "GLP" meal
- Storage temperature of food: Not stated

Details on mating procedure:

- M/F ratio per cage: 1/1
- Length of cohabitation: Maximum of 2 weeks
- Proof of pregnancy: Sperm in vaginal smear referred to as day 0 of pregnancy
- After 14 days of unsuccessful pairing replacement of first male by another male with proven fertility.
- Further matings after two unsuccessful attempts: no
- After successful mating each pregnant female was caged in Makrolon type MIII cages and provided with nesting material (cellulose wadding) toward the end of gestation.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The analyses were carried out at the Analytical Chemistry Laboratory of the Experimental Toxicology and Ecology of BASF SE. Analytical verifications of the stability of the test substance in the diet for a period of 48 days at room temperature were carried out prior to the start of the study. Homogeneity and concentration control analyses were carried out during the premating and the gestation periods. Duplicate samples were kept in reserve until after report finalization.

Duration of treatment / exposure:

In total, females were treated for 57 days and males treated for 36 days

Frequency of treatment:

Treated animals were fed ad libitum

Details on study schedule:

- Age at mating of the F0 mated animals in the study: 14-16 weeks

Dose / conc.:

1 500 ppm (nominal)

Dose / conc.:

4 000 ppm (nominal)

Dose / conc.:

12 000 ppm (nominal)

No. of animals per sex per dose:

10 males and 10 females per group

Control animals:

yes, plain diet

Details on study design:

- Dose selection rationale: Not given
- Rationale for animal assignment (if not random): Randomised according to body weight

Positive control:

No positive control included

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Daily; the parturition and lactation behaviour of the dams was also generally evaluated in the mornings in combination with the daily clinical inspection.
- Cage side observations checked in table [No.?] were included

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: Weekly for male and female parental animals with the following exceptions for female animals; during the mating period parental females were weighed on the day of positive evidence of sperm (GD 0) and on GD7, 14 and 20; Females with litter were weighed on the day after parturition (PND1) and on PND4.

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: Yes
- Time schedule for examinations: Weekly for male and female parental animals with the exception of: during the mating period (male and femal F0 animals); F0 females with evidence of sperm food consumption recorded on Gestation days 0-7, 7-14 and 14-20; F0 females giving birth to a litter food consumption was determined for post natal days 1-4.

Oestrous cyclicity (parental animals):

Not evaluated

Sperm parameters (parental animals):

Parameters examined in all male parental animals:
Weights and histopathological evaluaton of testes, epididymides, cauda epididymides and seminal vesicles

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: No

PARAMETERS EXAMINED
The following parameters were examined in F1 offspring:
Number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies at necropsy on PND4, body weight data, physical abnormalities

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

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals terminated approximately one week after the mating period (total of 36 days treatement)
- Maternal animals: All surviving animals terminated 2 weeks following PND4

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

HISTOPATHOLOGY / ORGAN WEIGHTS
The following tissues were weighed:
Adrenal glands, Brain, Cauda epididymis, Epididymides, Heart, Kidnes, Liver, Ovaries, Pituitary gland, Prostate, Testes, Seminal vesicles, Spleen, Thymus, Thyroid, Uterus

The following tissues were prepared for microscopic examination:
Adrenal glands, Aorta, Brain, Bone marrow (femur), Caecum, Coagulation glands, Colon, Duodenum, Eyes with optic nerve, Oesophagus, Mammary gland, Femure, Heart, Ileum, Jejunum, Kidneys, Larynx, Liver, Lungs, Lymph nodes (axillary and mesenteric), Nose, Oviducts, Pancreas, Pharynx, Pituitary gland, Prostate, Rectum, Salivary glands, Sciatic nerve, Seminal vesicles, Skeletal muscle, Skin, Spinal cord, Spleen, Sternum with marrow, Stomach, Trachea, Thymus, Thyroid gland, Urinary bladder, Uterus, Vagina

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring were sacrificed at PND 4 days of age.
- These animals were subjected to postmortem examinations (macroscopic and/or microscopic examination) as follows:

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

HISTOPATHOLOGY
- No histopathological examinations were performed.

Statistics:

Appropriate statistical methods were applied to all types of data generated.

Reproductive indices:

For the males, mating and fertility indices were calculated for F1 litters according to the following formulas:
- Male mating index (%) = number of males with confirmed mating/nmber of males placed with females x 100
- Male fertility index (%) = number of males proving fertility/number of males placed with females x 100
For the females, mating, fertility, gestation indices and delivery data were calculated for F1 litters according to the following formulas:
- Female mating index (%) = number of females mated/number of females placed with males x 100
- Female fertility index (%) = number of females pregnant/number of females mated x 100
- Gestation index (%) = number of females with live pups on the day of birth/ number of females pregnant x 100
- Live birth index (%) = number of liveborn pups at birth/total number of pups born x 100
- Postimplantation loss (%) = number of implantations-number of pups delivered/number of implantations x 100

Offspring viability indices:

- Pup number and status at delivery
- Pup viability/mortality - Viability index (%) = number of live pups on day 4 after birth/number of live pups on the day of birth x 100
- Sex ratio = number of live male or female pups on day0/4/number of live male and female pups on day 0/4 x 100

Clinical signs:

no effects observed

Dermal irritation (if dermal study):

not examined

Mortality:

not specified

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Reduced body weight gain and food consumption male and females treated at 12000 ppm

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Reduced body weight gain and food consumption in males and females treated at 12000 ppm

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

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Minimal central hepatocellular hypertrophy in females treated at 12000 ppm and minimal fatty change in females treated at 12000 and 4000 ppm

Histopathological findings: neoplastic:

not specified

Other effects:

no effects observed

Reproductive function: oestrous cycle:

not specified

Reproductive function: sperm measures:

no effects observed

Reproductive performance:

no effects observed

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
There were no clinical signs of ill health or reaction to treatment observed at 12000, 4000 or 1500 ppm and there were no treatment related mortalities among the F0 parent animals.

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS)
Decreased body weight gain in males weeks 0-1 treated at 12000 ppm (45% below controls); Decreased body weight gain in females treated at 12000 ppm in weeks 0-1 (73% below controls), gestation period (37% below controls) and during lactation (40 % below controls).
Reduced food intake in males treated at 12000 ppm in weeks 0-2 (10-18% below controls); Reduced food intake in females treated at 12000 ppm in weeks 0-1 (25% below controls), gestation period (20% below controls) and post natal days 1-4 (32% below controls).

TEST SUBSTANCE INTAKE (PARENTAL ANIMALS)
The dietary inclusion levels of 1500, 4000 and 12000 ppm correspond to 102, 266 and 758 mg/kg/day in males; 105, 279 and 705 mg/kg/day in non-pregnant females; 120, 340 and 824 mg/kg/day in pregnant females; 193, 468 and 1194 mg/kg/day in lactating females.

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS)
There were no effects reported on estrous cycle of female rats during the routine clinical observations.

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS)
There were no effects observed on the pathological assessment of the male reproductive tract that were indicative of any effects on sperm production.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
In males the mating index was 100% in all groups including controls. Fertility was proven for most of the F0 parental males within the scheduled mating interval for the F1 litter with the male fertility index ranging between 90% and 100% without showing any relation to dose level.
In females the mating index for the F1 litter was 100% in all groups. The fertility index varied between 90% in females treated at 1500 or 12000 ppm and 100% in control females and those treated at 4000 ppm. The mean duration of gestation was similar in all groups (i.e. between 21.6 and 21.9 days) and the gestation index was 100% in all groups. Implantation, prenatal development and delivery were not affected by the treatment since neither the mean number of implantation sites nor the postimplantation loss or the average litter size showed any statistically significant differences between the groups.

ORGAN WEIGHTS (PARENTAL ANIMALS)
Statistically significant absolute and relative increased liver weights in males and females treated at 12000 ppm and also in females treated at 4000 ppm.

GROSS PATHOLOGY (PARENTAL ANIMALS)
The liver was discoloured in males and females treated at 12000 ppm, however, this finding is not considered to be adverse.

HISTOPATHOLOGY (PARENTAL ANIMALS)
Minimal or slight central hepatocellular hypertrophy was observed in females treated at 12000 ppm. In addition a minimal fatty change was noted in females treated at 12000 or 4000 ppm.

Key result

Dose descriptor:

NOAEL

Effect level:

> 266 mg/kg bw/day

Based on:

test mat.

Sex:

male

Basis for effect level:

body weight and weight gain

food consumption and compound intake

organ weights and organ / body weight ratios

gross pathology

Key result

Dose descriptor:

NOAEL

Effect level:

> 105 mg/kg bw/day

Based on:

test mat.

Sex:

female

Basis for effect level:

body weight and weight gain

food consumption and compound intake

organ weights and organ / body weight ratios

gross pathology

histopathology: non-neoplastic

Key result

Dose descriptor:

NOAEL

Effect level:

> 758 mg/kg bw/day

Based on:

test mat.

Sex:

male

Basis for effect level:

reproductive function (sperm measures)

reproductive performance

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Dose descriptor:

NOAEL

Effect level:

> 705 mg/kg bw/day

Based on:

test mat.

Sex:

female

Basis for effect level:

reproductive performance

Remarks on result:

not determinable due to absence of adverse toxic effects

Clinical signs:

not examined

Dermal irritation (if dermal study):

not examined

Mortality:

not examined

Body weight and weight changes:

not examined

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not examined

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

not examined

Clinical signs:

no effects observed

Dermal irritation (if dermal study):

not examined

Mortality / viability:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Lower body weight gain in pups of the 12000 ppm group days PND1-4

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 examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Other effects:

not specified

Behaviour (functional findings):

not specified

Developmental immunotoxicity:

not specified

VIABILITY (OFFSPRING)
The rate of liveborn pups was not affected by the test substance as indicated by live birth indices of 100% in all groups. The viability index indicating pup mortality during lactation (PND 0-4) varied between 98% in the 1500 ppm group and 100% in all other groups. The sex distribution and sex ratios of live F1 pups on the day of birth and PND4 did not show any significant differences between control and treated groups.

CLINICAL SIGNS (OFFSPRING)
There were no test substance-related adverse clinical signs observed in any of the F1 pups.

BODY WEIGHT (OFFSPRING)
Mean body weights of the high-dose pups (12000 ppm) were statistically significantly below control on PND 4 (about 13% below control). Body weight gain for PND 1-4 was statistically significantly decreased in the high-dose F1 pups (about 38% below control).

SEXUAL MATURATION (OFFSPRING)
Not examined

ORGAN WEIGHTS (OFFSPRING)
Not examined

GROSS PATHOLOGY (OFFSPRING)
No findings were observed at gross necropsy in all F1 pups

HISTOPATHOLOGY (OFFSPRING)
Not examined

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

ca. 340 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Based on slightly reduced growth and development of offspring, secondary to maternal toxicity at the 4000 ppm treatment level

Clinical signs:

not examined

Dermal irritation (if dermal study):

not examined

Mortality / viability:

not examined

Body weight and weight changes:

not examined

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not examined

Histopathological findings:

not examined

Other effects:

not examined

Behaviour (functional findings):

not examined

Developmental immunotoxicity:

not examined

Key result

Reproductive effects observed:

no

Conclusions:

Under the conditions of this reproduction/developmental toxicity screening test the NOAEL (no observed adverse effect level) for reproductive performance and fertility was considered to be 12000 ppm for the F0 parental rats. The NOAEL for developmental toxicity in the F1 progeny of the test substance treated groups was found to be 4000 ppm toxicity based on slightly reduced growth and development of offspring, secondary to maternal toxicity.

Executive summary:

Under the conditions of this Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test in Wistar Rats treatment with Nerolidol showed general systemic toxicity in the F0 males at 12000 ppm (equivalent to 758 mg/kg/day) and in the F0 females at 12000 ppm (equivalent to 705 to 1194 mg/kg/day) and 4000 ppm (equivalent to 279 to 468 mg/kg/day). These effects were manifest as reductions in food intake and body weight gain and increased liver weights with associated histopathological hepatocellular changes including hypertrophy and fatty change. However, there were no reproductive toxicological effects seen in either males or females at the dose levels associated with systemic toxicity. The only sign of developmental toxicity was a slight reduction of offspring body weights/body weight gain at the high dose level of 12000 ppm. This was considered by the authors to be indicative of a temporary developmental delay secondary to the impaired well-being of the dams in this treatment group so the NOAEL for reproduction and fertility in the F0 rats was considered to be 12000 ppm (equivalent to 758 mg/kg/day for males and 705 mg/kg/day for females). This study is considered to be reliable without restriction (Klimisch 1) as it was GLP-compliant and was conducted according to OECD 422 and OPPTS 870.3650.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

705 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

One key study from read-across substance nerolidol is available, which is considered to be reliable without restrictions (Klimisch 1) as it was GLP-compliant and was conducted according to OECD 422 and OPPTS 870.3650.

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

This endpoint is completed using read-across from nerolidol. Read-across is appropriate as the test substance and nerolidol are very similar in chemical structure, differing only by the interchange of a hydroxyl group and double bond on carbon positions 1 and 2, and very similar in physico-chemical properties. For skin and eye toxicities, similar reactions were observed for both compounds, with nerolidol producing slightly more severe reactions than farnesol. The oral and dermal acute and repeat dose toxicity data show that the toxicity of farnesol and nerolidol are similar in order of magnitude when comparing dose levels expressed in terms of mg kg-1 bodyweight. Gene mutation and chromosome aberration tests show negative results in vitro for both compounds. Given the similarities in chemical and biological effects, it can be assumed that reproductive/developmental toxicity for farnesol can be read-across from nerolidol.

Under the conditions of this Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test in Wistar Rats treatment with Nerolidol showed general systemic toxicity in the F0 males at 12000 ppm and in the F0 females at 12000 and 4000 ppm. These effects were manifest as reductions in food intake and body weight gain and increased liver weights with associated histopathological hepatocellular changes including hypertrophy and fatty change. However, there were no reproductive toxicological effects seen in either males or females at the dose levels associated with systemic toxicity. Consequently, the NOAEL for reproduction and fertility in parental rats was determined to be 12000 ppm (equivalent to 758 mg/kg/day for males and 705 mg/kg/day for females). The slightly reduced growth (reduced body weight gain) recorded for the offspring of dams treated at 12000 ppm was considered to be secondary to maternal toxicity at this treatment level.

This study is considered to be reliable without restriction (Klimisch 1) as it was GLP-compliant and was conducted according to OECD 422 and OPPTS 870.3650. This data may be used as key data, as nerolidol is a suitable read-across source to the target substance based on similar chemical structure and hazard data.

Effects on developmental toxicity

Description of key information

The key information supporting the evaluation of reproductive toxicity of the test item is a regulatory subchronic repeated dose toxicity study with reproductive toxicity screen by oral administration of the read-across substance, Nerolidol, in rats, conducted according to OECD 422 and GLP. In this study, the No Observed Adverse Effect Levels (NOAELs) for fertility and reproduction were established following repeated daily treatment to the parent animals and NOAELs were also established for developmental toxicity to F1 offspring based on the limited data available in this screening study.Read-across is appropriate as the test substance and nerolidol are very similar in chemical structure, differing only by the interchange of a hydroxyl group and double bond on carbon positions 1 and 2, and very similar in physico-chemical properties.The oral and dermal acute and repeat dose toxicity data show that the toxicity of farnesol and nerolidol are similar in order of magnitude when comparing dose levels expressed in terms of mg/kg bodyweight.Given the similarities in chemical and biological effects, nerolidol is considered to be a suitable read-across substance.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

340 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

One key study from read-across substance nerolidol is available, which is considered to be reliable without restrictions (Klimisch 1) as it was GLP-compliant and was conducted according to OECD 422 and OPPTS 870.3650.

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

The NOAEL for developmental toxicity in the F1 progeny of the test substance treated groups was considered to be 4000 ppm (equivalent to 340 mg/kg/day) based on slightly reduced growth and development of offspring secondary to maternal toxicity.

Justification for classification or non-classification

There were no effects upon fertility, reproductive performance or adverse effect on pups observed at doses up to 12000 ppm (equivalent to 758 mg/kg bw/day in males and 705 mg/kg bw/day in females), for the read-across substance, Nerolidol. Therefore, it is concluded that the test item is also not classifiable as reproductive toxicant according to CLP Regulation (EC) No. 1272/2008.