Tetracosanol

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

No reproductive toxicity studies were available on tetracosan-1-ol.

In a reliable study conducted according to draft OECD guideline 422 with octadecan-1-ol, the parental NOAEL was 2000 mg/kg bw/day and the NOAEL for reproductive effects can be considered as 2000 mg/kg bw/day, the highest dose tested (Hansen, 1992b).

Data from a reliable study using dodecan-1-ol reported a parental NOAEL of 2000 mg/kg bw/day and a NOAEL for reproductive effects of 2000 mg/kg bw/day (highest dose level) (Hansen 1992a).

Data from a reliable one-generation reproduction study using docosan-1-ol in rats reported a NOAEL of 1000 mg/kg (Iglesias 2002a; rel 2).

A feeding studies reported a lack of effects on the reproductive organs of rats receiving hexan-1-ol (NOAEL 1127 mg/kg) (Scientific Associates Inc., 1966, rel 2). No adverse effects were noted at any of the dose levels administered during the study. No effects in reproductive organs have been observed in repeated dose studies with any category member.

Link to relevant study records

Reference

Reference 1

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

not stated

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

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)

Deviations:

no

Principles of method if other than guideline:

Conducted according to Draft OECD guideline 422 Combined repeated dose and reproductive/developmental toxicity screening test

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

not specified

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Moellegard Breeding Centre
- Age at study initiation: 8 (males) and 7 (females) weeks
- Weight at study initiation: not specified
- Fasting period before study: not specified
- Housing: 2 rats/cage for acclimatization period then individually
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±2
- Humidity (%): 55±10
- Air changes (per hr): not specified
- Photoperiod (hrs dark / hrs light): fluorescent light was on from 8 pm to 8 am

IN-LIFE DATES: no data

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on exposure:

DIET PREPARATION
- Diet preparation involved first mixing the octadecanol with the barley component, the proportion of which varied for each dose level. The other components of the diet were then added.
- Rate of preparation of diet (frequency): not specified
- Mixing appropriate amounts with (Type of food): IT chow 101 diet
- Storage temperature of food: not specified

Details on mating procedure:

- M/F ratio per cage: 1:1
- Length of cohabitation: up to 22 days
- Proof of pregnancy: vaginal plug referred to as day 0 or, if the plug was recorded during the morning, day 1 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: individually in steel wire cages type 3 until day 20 in pregnancy where the pregnant females were placed in macrolon cages type 3.
- Any other deviations from standard protocol: none

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

Exposure period: males 45 days, females up to 54 days
Premating exposure period (males): 14 days
Premating exposure period (females): 14 days
Duration of test: males 45 days, females up to 54 days

Frequency of treatment:

continuous in diet

Details on study schedule:

- Age at mating of the mated animals in the study: 10 (males) and 9 (females) weeks

Dose / conc.:

1 500 ppm (nominal)

Remarks:

100 mg/kg bw/day

Dose / conc.:

7 500 ppm (nominal)

Remarks:

500 mg/kg bw/day

Dose / conc.:

30 000 ppm (nominal)

Remarks:

2000 mg/kg bw/day

No. of animals per sex per dose:

12

Control animals:

yes, plain diet

Details on study design:

- Dose selection rationale: Doses chosen from the results of a preliminary test.
- Rationale for animal assignment (if not random): Randomized into 4 groups with the same mean body weight

Positive control:

none

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: No

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: not specified

BODY WEIGHT: Yes
- Time schedule for examinations: During the experiment the males were weighed once/week. The females were weighed during the premating period and during pregnancy once/week. Pup litter weight was determined on days 1 and 4 after birth.

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
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes

OTHER: haematology and clinical biochemistry conducted in the males

Oestrous cyclicity (parental animals):

Exposure was for 14 days premating covering at least 2 oestrous cycles. Ovaries were weighed and examined histopathologically at section (5 days after birth).

Sperm parameters (parental animals):

Parameters examined in male parental generation: other: Exposure 14 days premating, no specific sperm analyses carried out, the testes & epididymes were weighed and examined histopathologically.

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, postnatal mortality, presence of gross anomalies, weight gain, other: examined for internal malformations.

GROSS EXAMINATION OF DEAD PUPS:
no

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals sacrificed after 45 days of dosing
- Maternal animals: All surviving animals sacrificed on postnatal day 5

GROSS NECROPSY
Gross necropsy consisted of full macroscopic examination.

HISTOPATHOLOGY / ORGAN WEIGHTS
The liver, kidneys, thymus, testes and epididymides were weighed; the liver, kidneys, adrenals, brain, heart, spleen, ovaries, thymus, testes, epididymides and any organs showing abnormality on macroscopic examination were fixed and the tissues from all controls and top dose treated rats (except the thymus) plus abnormalities were examined.

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring were sacrificed at 5 days of age.
- These animals were subjected to postmortem examinations (macroscopic and/or microscopic examination) as follows:

GROSS NECROPSY
Gross necropsy consisted of external malformations including the head (especially eyes and cleft palate). Animals were then opened to the abdomen and thoracic cavity for a study of malformations of the internal organs.

HISTOPATHOLOGY / ORGAN WEIGHTS
No histopathology or organ weights measured.

Statistics:

Analysis of variance followed if significant differences were established by Dunnetts t-test to assess possible intergroup differences. For pregnancy rate a Chi-squared test was carried out to confirm lack of significance.

Reproductive indices:

Pregnancy rate, length of gestation, implantations, corpora lutea and resorptions were recorded.

Offspring viability indices:

none

Clinical signs:

not examined

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Other effects:

no effects observed

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

effects observed, treatment-related

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS): None reported

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS): No treatment related effects

TEST SUBSTANCE INTAKE (PARENTAL ANIMALS): Not reported

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS): Not reported

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS): Not reported

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS): There was no statistically significant difference in pregnancy rates (confirmed using a Chi-squared test) although they were reduced in treated groups C 92%, 100 & 500 mg/kg 75%, 2000 mg/kg/day 67% these were within the normal historical control range according to the authors (actual historical control data not presented).

ORGAN WEIGHTS (PARENTAL ANIMALS): There were no statistically significant dose related changes in organ weights including the testes, epididymides and ovaries.

GROSS PATHOLOGY (PARENTAL ANIMALS): There were no changes attributable to exposure to the test compound.

HISTOPATHOLOGY (PARENTAL ANIMALS): There were no treatment related histopathological changes including no effects in the testes and ovaries.

OTHER FINDINGS (PARENTAL ANIMALS): Duration of gestation was comparable in treated and control dams (mean 22 days for all groups) and no clinical biochemical findings, examined in the males only, were considered of biological significance. Haematological examination in the males only showed changes in plasma free cholesterol, triglycerides and glucose although the significance is unclear. The changes were observed at all doses levels but were not dose related and may be related to differences in dietary composition. There was no significant differences in the numbers of implantations between treated and control groups (Mean 13 in controls and low-dose, 15 in mid- and high-dose groups); resorptions mean for controls and low-dose 0, for mid- and high-dose 1; no significant differences between treated and control groups with respect to number of corpora lutea (mean controls 13, low and mid dose 14, high dose 15).

Key result

Dose descriptor:

NOAEL

Effect level:

2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects observed

Critical effects observed:

no

Clinical signs:

not examined

Mortality / viability:

not examined

Body weight and weight changes:

no effects observed

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

VIABILITY (OFFSPRING): Not examined

CLINICAL SIGNS (OFFSPRING): Not examined

BODY WEIGHT (OFFSPRING): Litter weights day 1 mean 69, 61, 75 and 75 g; Day 4 mean 96, 84, 101 and 101 g for controls, low, mid and high dose respectively

SEXUAL MATURATION (OFFSPRING): No treatment related effects.

ORGAN WEIGHTS (OFFSPRING): Not examined

GROSS PATHOLOGY (OFFSPRING): No treatment related effects

HISTOPATHOLOGY (OFFSPRING): Not examined

OTHER FINDINGS (OFFSPRING): No effect of treatment on litter size (mean litter size 11.73, 10.0, 13.6 and 13.38 for controls, low, mid and high dose respectively) and post natal survival until day 5 was similar in the treated and control groups.

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects observed

Critical effects observed:

no

Reproductive effects observed:

no

Conclusions:

In a reliable study conducted according to draft OECD guideline 422, parental NOAEL was 2000 mg/kg bw/day and the NOAEL for reproductive and developmental effects can be considered as 2000 mg/kg bw/day (highest dose level).

Executive summary:

Octadecan-1-ol has been tested for potential reproductive toxicity in a combined repeat dose reproductive/developmental toxicity screening study in rats conducted according to the draft OECD guideline 422 and in compliance with GLP. The materials were administered to male and female rats via the diet at concentrations up to 30,000 ppm during pre-mating, mating and gestation. Pregnancy rates, uterine parameters, time to pregnancy and gestation length indicated that fertility was not affected by exposure to octadecan-1-ol. There were no microscopic changes observed in the reproductive organs.

Reference 2

Endpoint:

one-generation reproductive toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

not stated

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

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

Principles of method if other than guideline:

Draft OECD 422 Combined Repeat dose and Reproductive/Developmental Toxicity Screening Test.

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
- Source: Moellegard breeding centre
- Age at study initiation: F 8 weeks, M 7 weeks
- Weight at study initiation: no data
- Fasting period before study: no data
- Housing: 2/cage, steel wire cages type 3 (up to day 20 of gestation); macrolon cages type 3 (from day 20 of gestation)
- Diet (e.g. ad libitum): IT chow 101, presumably ad libitum
- Water (e.g. ad libitum): acidified tapwater, ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +- 2
- Humidity (%): 55 +- 10
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: no data

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): no data
- Mixing appropriate amounts with (Type of food): IT chow 101
- Storage temperature of food:no data
- Preparation procedure: Diet preparation involved first mixing an aqueous dodecanol solution with the barley component, which varied for each dose level. The other components of the diet were then added.

Details on mating procedure:

- M/F ratio per cage: 1:1
- Length of cohabitation: 14 days
- Proof of pregnancy: vaginal plug recorded during the morning referred to as day 1 of pregnancy; vaginal plug recorded at lunch time or during the afternoon referred to as day 0 of pregnancy
- After 14 days of unsuccessful pairing replacement of first male by another male for up to 8 days
- Further matings after two unsuccessful attempts: no
- After successful mating each pregnant female was caged (how): in steel wire cages type 3 until day 20 of pregnancy, placed in macrolon cages type 3 thereafter
- Any other deviations from standard protocol: none

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

Exposure period: Males 41-44 days , females up to 54 days
Premating exposure period (males): 14 days
Premating exposure period (females): 14 days
Duration of test: Males 41-44 days, females up to 54 days

Frequency of treatment:

continuous in diet

Details on study schedule:

- One-generation study (only parental animals mated)

Dose / conc.:

1 500 ppm (nominal)

Remarks:

approx 100 mg/kg bw/day

Dose / conc.:

7 500 ppm (nominal)

Remarks:

approx 500 mg/kg bw/day

Dose / conc.:

30 000 ppm (nominal)

Remarks:

approx 2000 mg/kg bw/day

No. of animals per sex per dose:

12

Control animals:

yes, plain diet

Details on study design:

- Dose selection rationale: preliminary test via a dermal route
- Rationale for animal assignment (if not random): 2 days prior to the start of dosing, animals randomised into four groups with same mean body weight

Positive control:

none

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations included: mortality

DETAILED CLINICAL OBSERVATIONS: No data

BODY WEIGHT: Yes
- Time schedule for examinations: males once per week; females premating once per week

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption in g body weight gain/kg food per week calculated from the consumption and body weight gain data: Yes

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No

Oestrous cyclicity (parental animals):

no data (exposure was for 14 days premating covering at least 2 oestrous cycles; ovaries were weighed and examined histopathologically at necropsy)

Sperm parameters (parental animals):

Parameters examined in male parental generation: testis weight, epididymis weight

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: no (one-generation screening study)

PARAMETERS EXAMINED
- The following parameters were examined in F1 offspring: number of pups on days 1, 4 and 5; sex of pups on day 5; postnatal mortality from day 1 to day 4; weight gain from day 1 to day 4; mean body weight of male and female pups on day 5; presence of gross abnormalities on day 5

GROSS EXAMINATION OF DEAD PUPS: yes, on day 5, for external abnormalities including the head (especially the eyes and cleft palate), abdomen and thoracic cavity examined internally for malformations; possible cause of death was not determined for pups born or found dead

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals after 41-44 days of dosing
- Maternal animals: All surviving animals on day 5 after birth

ORGAN WEIGHT: males - liver, kidneys, thymus, testes, epididymides; females - liver, kidneys, thymus

ORGANS FIXED IN FORMALIN: males - liver, kidneys, adrenals, brain, heart, spleen, thymus, organs with pathological changes, testes and epididymides fixed in Bouin's solution; females - liver, kidneys, adrenals, brain, heart, spleen, ovaries, thymus, other organs with observed pathological changes

HISTOPATHOLOGY: Yes, control and top dose group, all fixed organs except thymus

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring not selected as parental animals and all F2 offspring were sacrificed at [#?] days of age: not applicable (1-generation study)

Statistics:

Using the SAS-stat program; analysis of variance; all statistically significant findings further evaluated by Dunnett's t-test; chi-squared test for pregancy rate

Reproductive indices:

pregnancy rate; length of gestation; numbers of corpora lutea, implantations, resorptions and pups at birth

Offspring viability indices:

number of pups at birth and on days 4 and 5, number of pups per litter, pup deaths between days 1 and 4

Clinical signs:

no effects observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

no effects observed

Other effects:

not examined

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

CLINICAL SIGNS AND MORTALITY
- Mortality and time to death: None
- Clinical signs: None reported

BODY WEIGHT AND WEIGHT GAIN
- Body weight gain: No differences between treated and controls of either sex.

TEST SUBSTANCE INTAKE (PARENTAL ANIMALS)
Males: 102.4, 530.8 and 2046.4 mg/kg bw/day (mean of values reported for 2 weeks prior to mating and 3 weeks after mating)
Females: 130.5, 657.5 and 2870.5 mg/kg bw/day (mean of values reported 2 weeks prior to mating)

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS)
no data

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS)
no data

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
- no statistically significant effects on pregnancy rate, length of gestation or numbers of corpora lutea, implantations, resorptions or pups at birth
- pregnancy rate was reduced in treated groups: 0 mg/kg bw/day 92%, 100 & 500 mg/kg bw/day 83%, 2000 mg/kg/day 75%; these were within the normal historical control range according to the investigators (actual historical control data not presented); lack of statistical significance confirmed using chi-squared test
- mean length of gestation: 23 days in all groups
- mean number of corpora lutea: 14 in all groups
- mean number of implantations: 13 in controls, 14 in all treated groups
- no resorptions in any group

ORGAN WEIGHTS (PARENTAL ANIMALS) (see table 2)
- There were no dose related changes in organ weights, including the testes, epididymides and ovaries; in males only there was a reduction in relative and absolute liver weights at the low dose level and a reduction in relative liver weight at mid doses, the top dose was comparable to controls.

GROSS PATHOLOGY (PARENTAL ANIMALS)
- There were no changes attributable to exposure to the test compound.

HISTOPATHOLOGY (PARENTAL ANIMALS)
- There were no treatment related histopathological changes.

OTHER (PARENTAL ANIMALS)
- Haematology and clinical chemistry data for parental males (reported elsewhere)

Key result

Dose descriptor:

NOAEL

Effect level:

> 2 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects observed

Remarks on result:

not determinable

Remarks:

no NOAEL identified

Clinical signs:

not examined

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

VIABILITY (OFFSPRING)
- no statistically significant effect
- litter size mean on day 1: controls 13.25, low dose 13.27, mid dose 13.2, high dose 13.33. 

CLINICAL SIGNS (OFFSPRING)
- no effects

BODY WEIGHT (OFFSPRING)
- no statistically significant effects
- mean litter weights at day 1 were 75, 75, 71 and 77 g and at day 4 106, 107, 101 and 104 g for control, low, mid and high dose respectively

SEXUAL MATURATION (OFFSPRING)
- not applicable (1-generation screening study)

ORGAN WEIGHTS (OFFSPRING)
- not applicable (1-generation screening study)

GROSS PATHOLOGY (OFFSPRING)
- no effects

HISTOPATHOLOGY (OFFSPRING)
- no data

OTHER FINDINGS (OFFSPRING)
- no statistically significant effects on pup body weight on day 5

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

> 2 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects observed

Remarks on result:

not determinable

Remarks:

no NOAEL identified

Reproductive effects observed:

no

Conclusions:

In a reliable study conducted to the draft OECD guideline 422, a parental NOAEL of > 2000 mg/kg bw/day (highest dose tested) was determined for male and female rats. No adverse effects were observed on reproductive parameters and the NOAEL for reproductive and developmental effects was also > 2000 mg/kg bw/day. The study was performed in compliance with GLP.

Executive summary:

Dodecan-1-ol has been tested for potential reproductive toxicity in a combined repeat dose reproductive/developmental toxicity screening study in rats conducted according to the draft OECD guideline 422 and in compliance with GLP. The materials were administered to male and female rats via the diet at concentrations up to 30,000 ppm (2000 mg/kg bw/day) during pre-mating, mating and gestation. Pregnancy rates, uterine parameters, time to pregnancy and gestation length indicated that fertility was not affected by exposure to octadecan-1-ol. There were no microscopic changes observed in the reproductive organs.

Reference 3

Endpoint:

one-generation reproductive toxicity

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

not stated

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

without detailed documentation

Qualifier:

according to guideline

Guideline:

other: ICH Harmonised Tripartite Guideline S5(R2) Detection of toxicity to reproduction for medicinal products and toxicity to male fertility

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 415 [One-Generation Reproduction Toxicity Study (before 9 October 2017)]

Deviations:

yes

Remarks:

(no postnatal observations of pups)

GLP compliance:

not specified

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Ltd.
- Age at study initiation: (P) males 6-7 wks, females 10-11 weeks
- Weight at study initiation: (P) males 193-240 g; females 208-262 g
- Fasting period before study: no
- Housing: according to the investigators "during the acclimation and premating periods, 10 rats (5 males and 5 females) were housed per TR18 stainless-steel cage..."; during mating, 1 male and 1 female housed in RB3-modified high-grade polypropylene cage with stainless-steel mesh lids and floors; during gestation, 5 females per RB3-modified cage; after mating, 5 males per TR18 cage
- Use of restrainers for preventing ingestion (if dermal): not applicable
- Diet (e.g. ad libitum): expanded rodent diet (Special Diet Services Ltd.), ad libitum
- Water (e.g. ad libitum): public supply, ad libitum
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18
- Humidity (%): 55
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: no data

Route of administration:

oral: gavage

Vehicle:

other: 1% w/w aqueous Tween 80

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
- test material weighed into glass container and heated to ~80 deg C until molten
- vehicle heated to 75 deg C
- test material and vehicle combined using coninuous magnetic stirring, 20% behenyl alcohol
- suspension cooled slowly to <60 deg C
- further cooled to 30 deg C
- slowly homogenized <=2 min
- cooled to room temperature
- 20% suspension prepared weekly
- 20% suspension provided top dose
- mid and low dose prepared on day of use by dilution with vehicle; 20% suspension magnetically stirred prior to removal of aliquots for dilution; dilutions hand swirled prior to magnetic stirring

VEHICLE
- Justification for use and choice of vehicle (if other than water): not stated
- Concentration in vehicle: 20, 2 and 0.2%
- Amount of vehicle (if gavage): 5 ml/kg bw
- Lot/batch no. (if required): no data
- Purity: 1% aqueous

Details on mating procedure:

- M/F ratio per cage: 1:1
- Length of cohabitation: not stated
- Proof of pregnancy: vaginal plug / sperm in vaginal smear referred to as day 0 of gestation
- After ... days of unsuccessful pairing replacement of first male by another male with proven fertility: no data
- Further matings after two unsuccessful attempts: no data
- After successful mating each pregnant female was caged (how): 5/cage; RB3-modified cages
- Any other deviations from standard protocol: OECD guideline 415 recommends that: pregnant females are house individually, the mating period should be 3 weeks

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

Males: from 71 days prior to mating, during mating and until females sacrificed
Females: from 15 days prior to mating, during mating, and up to day 17 of gestation; killed on day 20 of gestation

Frequency of treatment:

daily

Details on study schedule:

1-generation study

Dose / conc.:

10 mg/kg bw/day (nominal)

Dose / conc.:

100 mg/kg bw/day (nominal)

Dose / conc.:

1 000 mg/kg bw/day (nominal)

No. of animals per sex per dose:

22

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: previous repeated dose toxicity study NOAEL was 1000 mg/kg bw/day
- Rationale for animal assignment (if not random): no data

Positive control:

no

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations included: evidence of reaction to treatment, moribund condition, mortality

DETAILED CLINICAL OBSERVATIONS: No data

BODY WEIGHT: Yes
- Time schedule for examinations: males and females twice weekly prior to mating; males twice weekly after mating; females on gestation days 0, 3, 7, 10, 14, 18 and 20

FOOD CONSUMPTION :
- Food consumption: Yes
- Time schedule: males weekly prior to mating, females daily prior to mating, females on gestation days 0-2, 3-6, 7-9, 10-13, 14-17, 18-19

WATER CONSUMPTION: Yes
- Time schedule: males weekly prior to mating, females daily prior to mating, females on gestation days 0-2, 3-6, 7-9, 10-13, 14-17, 18-19

Oestrous cyclicity (parental animals):

10 days prior to mating, daily vaginal smears to assess regularity and duration of oestrus cycles

Sperm parameters (parental animals):

Parameters examined in male parental generations: testis weight, epididymis weight, sperm count in epididymides, sperm motility

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: no, F1 generation examined as foetuses on day 20 of gestation

PARAMETERS EXAMINED
The following parameters were examined in parental females and F1 offspring: numbers of implantation sites, early and late resorptions and viable foetuses; distribution of foetuses in each uterine horn; placental weight; macroscopic examination of placentae; number and sex of foetuses

EXAMINATION OF PUPS: yes, for external and internal abnormalities (visceral and skeletal)

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals following necropsy of the females
- Maternal animals: All surviving animals on day 20 of gestation

GROSS NECROPSY
- Gross necropsy of females consisted of reproductive endpoints only
- Gross necropsy of males consisited of macroscopic examination externally and internally; sperm assessment

HISTOPATHOLOGY / ORGAN WEIGHTS
No tissues were prepared for microscopic examination
Reproductive organs were weighed

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring were examined on day 20 of gestation
- These animals were subjected to examination as follows: each foetus weighed; detailed external examination; contents of cervical, thoracic and abdominal cavities removed from half the foetuses and examined and sex recorded; these foetuses stained for skeletal examination; remaining foetuses examined for visceral abnormalities

HISTOPATHOLOGY / ORGAN WEIGTHS
No tissues prepared for microscopic examination or weighed.

Statistics:

One-way analysis of variance, t-tests - body weight, body weight change, food and water consumption; Dunnetts' or Behren's-Fisher's tests - organ weights; nested analysis of variance, weighted t-tests - foetal and placental weights

Reproductive indices:

number of pregnant females, fertility

Offspring viability indices:

number of viable young (offspring evaluated as foetuses on day 20 of gestation)

Clinical signs:

no effects observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

not examined

Other effects:

not examined

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

no effects observed

Reproductive performance:

no effects observed

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
- females, no mortality
- males, one death in top dose group in week 6, not considered to be treatment related in the absence of toxic signs in any other animals

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS)
- no effects

REPRODUCTIVE FUNCTION: ESTROUS CYCLE (PARENTAL ANIMALS)
- no effects

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS)
- PREGNANCY RATE - no effects (22, 22, 22 and 21 in control, low, mid and high dose groups respectively)
- no effects

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
- no effects

ORGAN WEIGHTS (PARENTAL ANIMALS)
- males, reproductive organs, no effects

GROSS PATHOLOGY (PARENTAL ANIMALS)
- no effects

HISTOPATHOLOGY (PARENTAL ANIMALS)
- not examined

OTHER
- REPRODUCTIVE PARAMETERS
- Number of corpora lutea - no effects (17.8, 18.4, 18.7 and 18.9 for controls, low, mid and high dose respectively)
- Number of implantations - no effects (means 17.2, 17.0, 18.1 and 18.0 for controls, low, mid and high dose respectively)
- Number of viable young - no effects (means 16.4, 15.9, 17.0 and 16.9 for controls, low, mid and high dose  respectively)
- Sex ratio - no effects
- Number of resorptions (early or late) - no effects
- Pre-implantation loss - no effects (3.3, 8.3, 3.2,  5.8% for controls, low, mid and high dose respectively)
- Post-implantation loss - no effects (4.7, 6.4, 6.3 and 5.8% for controls, low, mid and high dose respectively)

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: overall effects

Clinical signs:

not examined

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

VIABILITY (OFFSPRING)
- no effects

CLINICAL SIGNS (OFFSPRING)
- not applicable, foetuses examined at day 20 of gestation

BODY WEIGHT (OFFSPRING)
- no effects

SEXUAL MATURATION (OFFSPRING)
- not applicable, foetuses examined at day 20 of gestation

ORGAN WEIGHTS (OFFSPRING)
- not applicable, foetuses examined at day 20 of gestation

GROSS PATHOLOGY (OFFSPRING)
- not applicable, foetuses examined at day 20 of gestation

HISTOPATHOLOGY (OFFSPRING)
- not applicable, foetuses examined at day 20 of gestation

OTHER FINDINGS (OFFSPRING)
- MACROSCOPIC EXAMINATION (OFFSPRING)
- no variations were observed that were not comparable to historical control values
- SKELETAL EXAMINATION (OFFSPRING)
- no variations were observed that were not comparable to historical control values
- VISCERAL EXAMINATION (OFFSPRING)
- no variations were observed that were not comparable to historical control values

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: overall effects

Reproductive effects observed:

no

Conclusions:

In a reliable study, conducted to a protocol similar to OECD guideline 415, an NOAEL of 1000 mg/kg bw/day was determined in the rat for reproductive effects. The study was performed in compliance with GLP.

Executive summary:

Docosan-1-ol (C22) did not affect reproductive parameters when administered orally at levels up to 1000 mg/kg/day to male and female rats during pre-mating (10 weeks for males and 2 weeks for females), mating and gestation.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

2 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

The selected study was conducted according to an appropriate OECD guideline.

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

The conclusion that the members of the aliphatic alcohol category (C6 to C24) are not expected to impair fertility is based on a weight of evidence approach using data from reproductive screening studies [C12 (dodecan-1-ol), C18 (octadecan-1-ol)], a fertility study [C22 (docosan-1-ol)], together with a lack of effect on the reproductive organs in repeat dose studies over the range of linear and essentially linear alcohols. The available data have been reviewed and discussed (Veenstra G, Webb Cet al., 2009). Based on this it is concluded that tetracosan-1 -ol is not expected to impair fertility.

The read-across substances were chosen as representative of the lack of effects of the category. A full discussion of the Category can be found in the Human Health Alcohols C6-24 Category report (PFA, 2016).

Dodecan-1-ol and octadecan-1-ol have been tested for potential reproductive toxicity in a combined repeat dose reproductive/developmental toxicity screening study in rats. The materials were administered to male and female rats via the diet at concentrations up to 30,000 ppm during pre-mating, mating and gestation. Pregnancy rates, uterine parameters, time to pregnancy and gestation length indicated that fertility was not affected by exposure to dodecan-1-ol or octadecan-1-ol. There were no microscopic changes observed in the reproductive organs (Hansen, 1992 a, Institute of Toxicology, 1992b). Docosan-1-ol (C22) did not affect reproductive parameters when administered orally at levels up to 1000 mg/kg/day to male and female rats during pre-mating (10 weeks for males and 2 weeks for females), mating and gestation (Iglesias et al., 2002a).

In a research publication, the test material (Alcohols, C10-16) was dissolved in polyethylene glycol 300 and administered to male rats by oral gavage at 209 mg/kg bw/day for 14 days. There were no adverse effects on testis weight relative to body weight; absolute testis weight data were not presented. An NOAEL of 209 mg/kg bw/day was identified from this very limited study (Central Toxicology Laboratory, 1984).

A feeding study reported a lack of effects on the reproductive organs of rats receiving hexan-1-ol (NOAEL 1127 mg/kg bw/day) and no adverse effects were noted at any of the dose levels administered during the study (Scientific Associates Inc. 1966).

A 90-day dietary repeat dose study on Alcohols, C14-15 showed an absence of effects on reproductive organs (Ito, 1978). In this study relative testes and ovary weights were increased at the 1% and/or 5% incorporation level, but at these levels a considerable reduction in bodyweight gain due to inanition was induced. The effects on relative organ weights were considered to be associated with the effects on body weight rather than a direct toxic effect. More importantly, there was no evidence of microscopic changes in the gonads. (Ito, 1978).

Discussion of trends in the Category of C6-24 linear and essentially-linear aliphatic alcohols:

Chronic and sub-chronic toxicity studies have shown that long chain alcohols (LCA) are of low toxicity, with no indication of treatment-related systemic effects. Furthermore, combined repeated-dose studies with developmental endpoints, as well as reproductive toxicity screening studies and developmental studies showed no effects at the highest dose tested for any of the Category members for which data are available.

It is concluded that the members of the LCAAs (C6 to C22) are not expected to impair fertility based on the weight of evidence approach using data from reproductive screening studies (C12 – dodecan-1-ol, C18 – octadecan-1-ol) a fertility study (C22 – docosan-1-ol) together with a lack of effect on the reproductive organs in repeat dose studies over the range of linear and essentially linear LCAAs. In addition, weight of evidence from across the category suggests that members of the LCAAs (C6 to C22) are unlikely to cause developmental effects.

The relatively small amounts of absorption that may occur across all common physiological routes (dermal, oral, inhalation) will be rapidly and efficiently metabolised in vivo to the corresponding fatty acid; a substance family which is exempt under REACH. These metabolic products are subsequently rapidly eliminated or may be utilised by biochemical systems in vivo, meaning that bioaccumulation is very unlikely.

It is therefore considered that further reproductive toxicity testing of members of Category is not required.

Fertility datafor the Category

	CAS	CHEMICAL NAME	NOAEL** (mg/kg)	Study type* / Species / Effects (Reference)	Rel.
C5	123-51-3	Isoamyl alcohol Supporting Substance		RDT* Rat: None (Carpanini, 1973)	2
C6	111-27-3	Hexan-1-ol	370	RDT*: Dog: none (Sc. Ass. 1966b)	2
C6	111-27-3	Hexan-1-ol	1127	RDT: Rat: none (Sc. Ass. 1966a)	2
C7	111-70-6	Heptan-1-ol		Supporting substance
C8	111-87-5	Octan-1-ol		Not expected to impair fertility based on read across from structurally analogous substances.	2
C9	143-08-8	Nonan-1-ol		Not expected to impair fertility based on read across from structurally analogous substances.
C10	112-30-1	Decan-1-ol		Not expected to impair fertility, based on read across from structurally analogous substances.
C11	112-42-5	Undecan-1-ol		Not expected to impair fertility, based on read across from structurally analogous substances.
C12	112-53-8	Dodecan-1-ol	2000**	Fert* Rat: None (Hansen,1992a )	2
C13	112-70-9	Tridecan-1-ol Supporting		RDT Rat: None (Rhodes, 1984)	2
C8	60435-70-3	2-methylheptan-1-ol		Not expected to impair fertility based on read across from structurally analogous substances.
C9	68515-81-1	Nonan-1-ol, branched and linear		Not expected to impair fertility based on read across from structurally analogous substances.
C10	90342-32-8	Decan-1-ol, branched and linear		Not expected to impair fertility, based on read across from structurally analogous substances as weight of evidence.
C11	128973-77-3	Undecan-1-ol, branched and linear		Not expected to impair fertility, based on read across from structurally analogous substances as weight of evidence.
C13	90583-91-8	Tridecan-1-ol, branched and linear Supporting		Not expected to impair fertility	2
C7-9		Alcohols, C7-9- linear and branched		Not expected to impair fertility, based on read across from structurally analogous substances as weight of evidence.
C9-11		Alcohols, C9-11-branched and linear		Not expected to impair fertility, based on read across from structurally analogous substances as weight of evidence.
C11-13		Reaction mass of 2-methyldecan-1-ol and 2-propyloctan-1-ol and 2-ethylnonan-1-ol and 2-butylheptan-1-ol		Not expected to impair fertility, based on read across from structurally analogous substances as weight of evidence.
C12-13	75782-86-4	Alcohols, C12-13		No data was available for the C12-13 alcohols for this endpoint. Data was therefore read across from hexan-1-ol, docosan-1-ol, dodecan-1-ol and octadecan-1-ol as weight of evidence.
C12-13	740817-83-8	Alcohols, C12-13-branched and linear		No data was available for the C12-13 alcohols for this endpoint. Data was therefore read across from hexan-1-ol, docosan-1-ol, dodecan-1-ol and octadecan-1-ol as weight of evidence
C12-15	90604-40-3	Alcohols, C12-15-branched and linear		Not expected to impair fertility, based on read across from structurally analogous substances as weight of evidence.	2

References:

PFA (2016). C6-24 Alcohols Category Report: Human Health. Version number:01. Peter Fisk Associates Ltd. February 2016

Veenstra G, Webb C et al., (2009) Human health risk assessment of long chain alcohols. Ecotoxicology and environmental safety 71 1016-1030

 

Effects on developmental toxicity

Description of key information

No developmental toxicity studies were available on tetracosan-1 -ol by any route. In a guideline study with C7-11 branched and linear, the NOAEL for both maternal and developmental toxicity was 1440 mg/kg bw/day (Hellwig & Jäckh 1997) and in a similar study with octan-1-ol the NOAEL for developmental toxicity was 1300 mg/kg bw/day (Hellwig & Jäckh 1997). Oral NOAELs of 2000 mg/kg bw/day were determined in developmental toxicity screening tests with dodecan-1-ol and octadecan-1-ol (Hansen 1992a, 1992b).

Link to relevant study records

Reference

Reference 1

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

not stated

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Principles of method if other than guideline:

conducted according to Draft OECD 422 Combined repeat dose and reproductive/developmental toxicity screening test

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Wistar

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Moellegard Breeding Centre
- Age at study initiation: 8 (males) and 7 (females) weeks
- Weight at study initiation: not specified
- Fasting period before study: Not specified
- Housing: 2 rats/cage for acclimatization period then individually
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±2
- Humidity (%): 55±10
- Air changes (per hr): not specified
- Photoperiod (hrs dark / hrs light): fluorescent light was on from 8 pm to 8 am

IN-LIFE DATES: no data

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on exposure:

DIET PREPARATION
- Diet preparation involved first mixing the octadecanol with the barley component, the proportion of which varied for each dose level. The other components of the diet were then added.
- Rate of preparation of diet (frequency): not specified
- Mixing appropriate amounts with (Type of food): IT chow 101 diet
- Storage temperature of food: not specified

Analytical verification of doses or concentrations:

no

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: 1:1
- Length of cohabitation: up to 22 days
- After 14 days of unsuccessful pairing replacement of first male by another male with proven fertility.
- Further matings after two unsuccessful attempts: no
- Proof of pregnancy: vaginal plug referred to as day 0 or, if the plug was recorded during the morning, day 1 of pregnancy
- Any other deviations from standard protocol: none

Duration of treatment / exposure:

Females up to 54 days, premating, mating and gestation until post natal day 5.
Males also treated.

Frequency of treatment:

continuous in diet

Duration of test:

From 14 days prior to mating then throughout mating and gestation until post natal day 5

Dose / conc.:

1 500 ppm (nominal)

Remarks:

100 mg/kg bw/day

Dose / conc.:

7 500 ppm (nominal)

Remarks:

500 mg/kg bw/day

Dose / conc.:

30 000 ppm (nominal)

Remarks:

2000 mg/kg bw/day

No. of animals per sex per dose:

12

Control animals:

yes, plain diet

Details on study design:

- Dose selection rationale: Doses chosen from the results of a preliminary test.
- Rationale for animal assignment (if not random): Randomized into 4 groups with the same mean body weight

Maternal examinations:

CAGE SIDE OBSERVATIONS: No

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: not specified

BODY WEIGHT: Yes
- Time schedule for examinations: During the experiment the males were weighed once/week. The females were weighed during the premating period and during pregnancy once/week. Pup litter weight was determined on days 1 and 4 after birth.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on postnatal day 5
- Organs examined: liver, kidney, adrenals, brain, heart, spleen, ovaries, thymus and other organs with observed pathological changes.

OTHER: Total gross pathological examinations were performed on each animal at necropsy and organ weights determined for the liver, kidneys and thymus.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: No data
- Number of late resorptions: No data
- Other: number of resorptions was examined but it is not specified whether these were early or late.

Fetal examinations:

- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: all per litter
- Skeletal examinations: No
- Head examinations: Yes: all per litter

Statistics:

Statistical analysis made on all data using the SAS-stat program. All statistically significant findings were further evaluated by means of Dunnett’s t-test to assess possible inter-group differences.

Indices:

Pregnancy rate

Historical control data:

none

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
- Body weight: No treatment related effects.
- Food/water consumption: No treatment related effects.
- Description, severity, time of onset and duration of clinical signs: None reported.
- Pregnancy rate: There was no statistically significant difference in pregnancy rates (confirmed using a Chi-squared test) although they were reduced in treated groups C 92%, 100 & 500 mg/kg 75%, 2000 mg/kg/day 67% these were within the normal historical control range according to the investigators (actual historical control data not presented).
- Fertility index: Not reported
- Precoital interval: Not reported
- Duration of gestation: Comparable in treated and control dams.
- Gestation index: Not reported
- Changes in lactation: Not reported
- Changes in estrus cycles: Not reported
- Mortality: None
- Number of implantations: No significant differences in the numbers of implantations between treated and control groups. (Mean 13 in controls and low dose, 15 in mid and high dose groups). Resorptions mean for controls and low dose 0, for mid and high dose 1).
- Number of corpora lutea: No significant differences between treated and control groups (mean controls 13, low and mid dose 14, high dose 15).
- Ovarian primordial follicle counts: Not reported

Key result

Dose descriptor:

NOAEL

Effect level:

2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: No adverse effect observed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
- Litter size and weights: No effect of treatment (mean litter size 11.73, 10.0, 13.6 and 13.38 for controls, low, mid and high dose respectively). Litter
weights day 1 mean 69, 61, 75 and 75 g; Day 4 mean 96, 84, 101 and 101 g for controls, low, mid and high dose respectively)
- Sex and sex ratios: No treatment related effects.
- Post natal survival until day 5: Similar in treated and control groups.
- Foetal anomalies: There were no treatment related changes in the incidence of external or visceral malformations visible on macroscopic examination.

Key result

Dose descriptor:

NOAEL

Effect level:

2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effect observed

Abnormalities:

not specified

Developmental effects observed:

no

Conclusions:

In a reliable study, development was assessed as part of a combined repeat dose and reproductive/developmental toxicity study, conducted according to draft OECD guideline 422. The NOAEL for maternal and foetotoxicity in rats was 2000 mg/kg bw/day (highest dose level). There was no evidence of teratogenicity from the limited examination of the pups that was carried out. The result is read across from octadecan-1-ol (CAS 112-92-5).

Executive summary:

Based on the weight of evidence from other alcohols across the category and the combined repeat dose/reproductive/developmental study with octadecan-1-ol, it is concluded that octadecan-1-ol is unlikely to be a developmental toxicant in the absence of maternal toxicity.

Reference 2

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

not stated

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline available

Principles of method if other than guideline:

Draft OECD 422 Combined Repeat dose and Reproductive/Developmental Toxicity Screening Test.

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Wistar

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Moellegard breeding centre
- Age at study initiation: F 8 weeks, M 7 weeks
- Weight at study initiation: no data
- Fasting period before study: no data
- Housing: 2/cage, steel wire cages type 3 (for males and for females up to day 20 of gestation); macrolon cages type 3 (for females from day 20 of gestation)
- Diet (e.g. ad libitum): IT chow 101, presumably ad libitum
- Water (e.g. ad libitum): acidified tapwater, ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +- 2
- Humidity (%): 55 +- 10
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: no data

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): no data
- Mixing appropriate amounts with (Type of food): IT chow 101
- Storage temperature of food: no data
- Preparation procedure: Diet preparation involved first mixing an aqueous dodecanol solution with the barley component, which varied for each dose level. The other components of the diet were then added.

Analytical verification of doses or concentrations:

no

Details on mating procedure:

- Impregnation procedure: cohoused with treated males
- If cohoused:
- M/F ratio per cage: 1:1
- Length of cohabitation: 14 days
- After 14 days of unsuccessful pairing replacement of first treated male by another treated male for up to 8 days
- Further matings after two unsuccessful attempts: no
- Verification of same strain and source of both sexes: yes
- Proof of pregnancy: vaginal plug recorded during the morning referred to as day 1 of pregnancy; vaginal plug recorded at lunch time or during the afternoon referred to as day 0 of pregnancy
- Any other deviations from standard protocol: none

Duration of treatment / exposure:

Females: up to 54 days (premating, mating and gestation until post natal day 5)
Males: 41-44 days (including 14 premating)

Frequency of treatment:

continuous in diet

Duration of test:

pups examined on postnatal day 5, following continuous treatment of male and female parents from 14 days prior to mating

Dose / conc.:

1 500 ppm (nominal)

Remarks:

approx 100 mg/kg bw/day

Dose / conc.:

7 500 ppm (nominal)

Remarks:

approx 500 mg/kg bw/day

Dose / conc.:

30 000 ppm (nominal)

Remarks:

approx 2000 mg/kg bw/day

No. of animals per sex per dose:

12 male and 12 female parental animals per dose

Control animals:

yes, plain diet

Details on study design:

- Dose selection rationale: preliminary test apparently via a dermal route
- Rationale for animal assignment (if not random): 2 days prior to the start of dosing, animals randomised into four groups with same mean body weight

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations included: mortality

DETAILED CLINICAL OBSERVATIONS: No data

BODY WEIGHT: Yes
- Time schedule for examinations: females - premating once per week

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption in g body weight gain/kg food per week calculated from the consumption and body weight gain data: Yes

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on postnatal day (parental females): 5
- Organs examined (parental females): organ weights of liver, kidneys, thymus; organs fixed in formalin - liver, kidneys, adrenals, brain, heart, spleen, ovaries, thymus, other organs with observed pathological changes; histopathology - control and top dose group, all fixed organs except thymus

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: No
- Number of late resorptions: No
- Other:
- Total number of resorptions: Yes

Fetal examinations:

- On postnatal day 5, the pups were weighed and examined macroscopically for external malformations then sexed and examined for internal malformations, including:
- External examinations: Yes: all per litter
- Head examinations: Yes: all per litter
- Soft tissue examinations: No
- Skeletal examinations: No

Statistics:

Using the SAS-stat program; analysis of variance; all statistically significant findings further evaluated by Dunnett's t-test; chi-squared test for pregancy rate

Indices:

numbers of corpora lutea, implantations, resorptions and pups at birth and on days 4 and 5

Historical control data:

no data

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
- no mortality
- no statistically significant effects on body weight
- no statistically significant effects on organ weights or pathology

Dose descriptor:

NOAEL

Effect level:

2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: No adverse effects observed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
- no statistically significant effects on numbers of corpora lutea, implantations, resorptions or pups at birth; no statistically significant abnormalities in pups (see table 1)

Dose descriptor:

NOAEL

Effect level:

2 000 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: No adverse effects observed

Abnormalities:

not specified

Developmental effects observed:

no

Table 1: Developmental toxicity data

Observation	Dose (mg/kg bw/day) (nominal via diet)
	0	100	500	2000
Pregnancy rate (%)	92	83	83	75
Number of litters	12	11	10	9
Mean (±SD) number of corpora lutea	14±1.7	14±0.9	14±1.5	14±1.6
Mean (±SD) number of implantations	13±2.4	14±1.4	14±1.9	14±1.1
Total number of resorptions	0	0	0	0
Total number of pups (day 1)	159	146	132	120
Mean number of pups per litter (day 1)^b	13.25	13.27	13.20	13.33
Mean (±SD) litter weight (day 1) (g)	75±12.9	75±7.3	71±8.9	77±5.5
Total number of pups (day 4)	156	143^a	125	118
Total number of pup deaths (days 1-4)	3	3	7	2
Mean (±SD) litter weight (day 4) (g)	106±14.9	107±9.9	101±12.9	104±9.8
Mean (±SD) litter weight gain (day 4) (g)	31±8.5	32±4.5	30±6.3	27±7.8
Total number of pups (day 5) number of males number of females	156 70 86	144^a 55 89	125 61 63	118 62 56
Sex Ratio (% Male)^b	45	38	49	53
Mean (±SD) male pup body weight (day 5) (g)	9±0.7	9±0.5	9±1.2	9±1.1
Mean (±SD) female pup body weight (day 5) (g)	10±0.9	10±0.7	10±1.2	9±1.1
Postmortem findings - pups (day 5)	hydronephrosis (1 female), unilateral dil. renal pelvis (1 male), yellow spots on liver (1 male)	bilateral dil. renal pelvis (2 females), unilateral dil. renal pelvis (1 female)		aplasia testisuni. (1 male)

^aAs reported in study report

^bCalculated for this table

Conclusions:

In a reliable study conducted to the draft OECD guideline 422, the NOAEL for maternal and developmental toxicity was 2000 mg/kg bw/day, the highest dose tested. The study was performed in compliance with GLP.

Reference 3

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

group sizes are smaller than recommended 8-10 pregnant females rather than 20

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

group sizes are smaller than recommended; 8-10 pregnant females rather than 20

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

other: Wistar outbred-strain Chbb/THOM

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Supplied by Dr K. Thomae, GmbH, Biberach, Germany.
- Age at study initiation: 68-85 days
- Weight at study initiation: 214-233 g
- Fasting period before study: no data
- Housing: DK III stainless steel wire-mesh cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Air changes (per hr): "fully air conditioned rooms"
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

other: Doubly-distilled water containing about 0.005% Cremophor EL (as emulsifier)

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
Prepared daily in aqueous emulsions under rapid stirring


VEHICLE
- Justification for use and choice of vehicle: no data
- Concentration in vehicle: Adjusted to give constant volume
- Amount of vehicle: 5 ml/kg
- Lot/batch no.: no data
- Purity: no data

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Gas chromatography

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: One to four untreated females were mated with one untreated fertile male
- Length of cohabitation: "overnight"
- Verification of same strain and source of both sexes: yes
- Proof of pregnancy: sperm in vaginal smear referred to as day 0 of pregnancy

Duration of treatment / exposure:

gestation days 6-15

Frequency of treatment:

daily

Duration of test:

20 days

Dose / conc.:

130 mg/kg bw/day

Dose / conc.:

650 mg/kg bw/day

Dose / conc.:

975 mg/kg bw/day

Dose / conc.:

1 300 mg/kg bw/day

No. of animals per sex per dose:

8-10 females

Control animals:

yes, concurrent vehicle

Details on study design:

no data

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Daily


DETAILED CLINICAL OBSERVATIONS: No data


BODY WEIGHT: Yes
- Time schedule for examinations: Daily


POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 20
- Organs examined: Ovaries and uterus

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: half per litter
- Soft tissue examinations: Yes: half per litter
- Skeletal examinations: Yes: half per litter
- Head examinations: No

Statistics:

Dunnetts test for most reproductive parameters and Fischers exact test for evaluaton of conception rate and all foetal findings.

Indices:

Conception rates and pre & post implantation losses were calculated.

Historical control data:

Not presented

Details on maternal toxic effects:

Maternal toxic effects:yes

Details on maternal toxic effects:
A dose-related increase in maternal toxicity with increasing severity of clinical signs (including lateral and abdominal position, unsteady gait, salivation, piloerection, nasal discharge and pneumonia) was observed in all treatment groups, compared to the controls. Two dams died in each of the groups (of ten rats) receiving the test material at 650, 975 and 1300 mg/kg bw/day, compared to no deaths in the dams receiving 130 mg n-octanol/kg bw/day or in the controls. A slight decrease in food consumption and body weight gain was observed in those female rats administered n-octanol at 650 mg/kg bw/day and above.

The number of pregnant dams per dose level was 10/10, 9/10, 8/10 and 8/10 in the dams administered the test material at 130, 650, 975, and 1300 mg/kg bw/day, respectively, compared to 9/10 in the water controls and 10/10 in the aqueous emulsifier. The number of resorptions, implantations, corpora lutea were comparable to controls (Number of resorptions (all)/dam (mean) 1.0, 1.4 (controls), and 1.2, 0.7, 0.8 and 1.3 in treated groups from low - high. Number of implantation sites/dam (mean) 14.7, 16.0 (controls), and 14.7, 15.4, 13.8 and 14.5 from treated groups low - high. Number of corpora lutea/dam (mean) 14.8, 16.3 (controls), and 15.0, 16.0, 14.9 and 14.5 in treated groups low - high.) Duration of pregnancy, and uterine and placental weights, were also comparable between treatment groups, and controls.

Dose descriptor:

NOAEL

Effect level:

130 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: Slight clinical signs seen at lowest tested dose, more marked at higher doses and associated with minor reductions in body weight gain and food consumption

Abnormalities:

no effects observed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
No dead fetuses were observed and mean number of live foetuses/dam were unaffected by treatment ( 13.5, 14.7, 13.0 and 13.2 in treated groups receiving 130, 650, 975 or 1300 mg/kg bw/day, respectively, compared to 13.7 and 14.6 in controls). Litter size and weights were comparable in treated and control groups. Sex ratio was not reported. No treatment-related statistically significant and/or dose-related increases in the incidence of fetuses (or litters) with malformations, variations and retardations were observed, compared to controls. (Litters with malformations number 2 (22%), 3 (30%) (controls); 3 (30%), 3 (43%), 2 (25%) and 1 (17%) in treated groups low to high. Litters with variations number 8 (89%), 10 (100%) (controls); 10 (100%), 7 (100%); 7 (88%) and 5 (83%) in treated groups low to high. Litters with retardations number 8 (89%), 9 (90%) (controls);  9 (90%), 7 (100%), 8 (100%) and 5 (83%) in treated groups low to high. The authors note that "all foetal values were within the range of biological variation". A single cheiloschisis (cleft lip) and  one anophthalmy (eye loss) in the top-dose group was considered coincidental and not biologically relevant. 

Dose descriptor:

NOAEL

Effect level:

1 300 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: no adverse effects observed

Abnormalities:

no effects observed

Developmental effects observed:

no

Conclusions:

In a reliable study, performed to a protocol similar to OECD guideline 414, an NOAEL of 130 mg/kg bw/day (the lowest dose tested) was determined for maternal toxicity and an NOAEL of 1300 mg/kg bw/day for teratogenicity and foetotoxicity (the highest dose tested). The study was performed in compliance with GLP.

Executive summary:

Administration of octan-1-ol at daily gavage doses of 0, 130, 650, 975 or 1300 mg/kg resulted in significant, dose-related maternal toxicity, including clinical signs (depression, nasal discharge and pneumonia), and slight decreases in body weight gain and food consumption at 650, 975 or 1300 mg/kg/day. No adverse effects were recorded on foetal and developmental parameters.

Reference 4

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

group sizes are smaller than recommended, 10 pregnant females rather than 20; some omissions in reporting

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

(only 10 animals per group instead of the 20 indicated in guideline; some omissions in reporting)

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

other: Wistar Chbb/THOM

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr K Thomae GmbH, Biberach, Germany
- Age at study initiation: 68-85 days (females)
- Weight at study initiation: 214-233 g (females)
- Fasting period before study: no data
- Housing: singly in stainless steel wire-mesh cages
- Diet (e.g. ad libitum): ground Kliba feed 343 rat/mouse/hamster, ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Air changes (per hr): no data (air-conditioned)
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: no data

Route of administration:

oral: gavage

Vehicle:

other: double-distilled water with Cremophor EL as emulsifier

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: emulsified in double-distilled water containing 0.005% Cremophor EL. Prepared daily using a high-speed sonicator; a magnetic stirrer was used to keep the emulsion homogenous during dosing.

VEHICLE
- Justification for use and choice of vehicle (if other than water): to ensure even distribution of the test material
- Concentration in vehicle: 28.8, 144 or 288 mg/ml
- Amount of vehicle (if gavage): 5 ml/kg bw/day

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Concentrations analysed by gas chromatography after homogenization by the addition of dioxane.

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: 1 male to 1-4 females
- Length of cohabitation: overnight
- Further matings after two unsuccessful attempts: no
- Verification of same strain and source of both sexes: yes
- Proof of pregnancy: sperm in vaginal smear referred to as day 0 of pregnancy
- Any other deviations from standard protocol: no

Duration of treatment / exposure:

days 6-15 post coitum

Frequency of treatment:

daily

Duration of test:

20 days

Dose / conc.:

144 mg/kg bw/day

Dose / conc.:

720 mg/kg bw/day

Dose / conc.:

1 400 mg/kg bw/day

No. of animals per sex per dose:

8-10 females

Control animals:

yes, concurrent vehicle

other: double-distilled water

Details on study design:

- Dose selection rationale: based on equimolar dose levels as this was a study to compare toxicity of various C7-11 alcohols
- Rationale for animal assignment (if not random): random

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: daily

BODY WEIGHT: Yes
- Time schedule for examinations: daily

FOOD CONSUMPTION: yes

WATER CONSUMPTION: no

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day #20
- Organs examined: uterus

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
- Other: live foetuses, dead foetuses, numbers of implantations were shown as: live foetuses, dead implantations, early resorptions (stained), early & late resorptions (unnstained), dead foetuses; conception rates and pre & post implantation losses were calculated.

Fetal examinations:

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

Statistics:

Dunnetts test for most reproductive parameters and Fishers exact test for evaluaton of conception rate and all foetal findings.

Indices:

no data

Historical control data:

none

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
No maternal toxicity or deaths occurred. There were no differences in body weight gain between the treated and control groups on days 0, 6, 15 or 20 and no differences in food consumption was evident. No differences were seen in the uterus, placental and foetal weights and the number of corpora lutea, implantation sites and live foetuses per dam were similar between the groups.

- Number pregnant per dose level: water control 9, aqueous emulsifier control 10, 144 mg/kg bw/day 9, 720 mg/kg bw/day 10, 1440 mg/kg bw/day 8.
- Number aborting: None
- Number of resorptions: comparable in treated and control groups. Resorptions/dam (mean) 1.2, 1.1 (control groups) 1.0, 1.2 and 1.1 for low, mid and high dose groups respectively.
- Number of implantations: comparable in treated and control groups. Implantation sites/dam (mean) 15.0, 15.7 (control groups) 14.8, 15.8 and 13.9 for low, mid and high dose groups.
- Post implantation loss: comparable in treated and control groups.
- Number of corpora lutea: comparable in treated and control groups. Corpora lutea/dam (mean) 16.1, 16.0 (control groups) 17.0, 17.0 and 15.6 for low, mid and high dose groups respectively.
- Duration of Pregnancy: comparable in treated and control groups.

No haematology, clinical chemistry, macro- or microscopic examinations were carried out and organs were not weighed (other than the uterus).

Dose descriptor:

NOAEL

Effect level:

1 440 mg/kg bw/day (actual dose received)

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Dose descriptor:

NOAEL

Effect level:

1 440 mg/kg bw/day (actual dose received)

Based on:

test mat.

Basis for effect level:

other: developmental toxicity

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
No embryotoxic effects were detected that were attributed to the treatment. Similar numbers of abnormalities occurred in the treated and control groups for the following parameters: bilateral renal pelvis, hydroureter, thoracic vertebral body dumbbell shaped, skeletal variations and skeletal retardations.

- Litter size and weights: comparable in treated and control groups. Foetal weights (mean) 3.8, 3.82 (controls) 3.88, 3.79 and 3.82 for low, mid and high dose groups respectively.
- Number viable: viability was comparable to controls. Live foetuses/dam (mean) 13.8, 14.6 (controls) 13.8, 14.6 and 12.8 for low, mid and high dose groups respectively.
- Sex ratio: Not reported.
- Total malformations, variations and retardations: the incidence was unaffected by treatment. Litters (%) with malformations (no. of litters) 11.1% (1), 20.0% (2)(controls) 11.1% (1), 40.0% (4) and 12.5% (1) for low, mid and high dose groups respectively.
- Litters (%) with variations (no. of litters) 88.9% (8), 100% (10) (controls) 100% (9), 100% (10) and 100% (8) for low, mid and high dose groups respectively.
- Litters (%) with retardations (no. of litters) 88.9% (8), 100% (10) (controls) 77.8% (7), 90.0% (9) and 87.5% (7) for low, mid and high dose groups respectively.

Dose descriptor:

NOAEL

Effect level:

1 440 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: no adverse effects observed

Abnormalities:

not specified

Developmental effects observed:

no

Conclusions:

In a reliable study, conducted to a protocol similar to OECD guideline 414, a mixture of mainly linear C7-9-11 alcohols exhibited no maternal or foetal toxicity after oral administration to rats on gestation days 6-15 at up to 1440 mg/kg bw/day. The study was performed to GLP.

Executive summary:

C7-11-branched and linear alcohols was administered at daily gavage doses of 0, 140, 720 and 1440 mg/kg bw/day to pregnant rats. No maternal toxicty was observed, and no adverse effects were recorded on foetal and developmental parameters.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

2 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

The selected study was conducted according to an appropriate OECD guideline.

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 Category hypothesis is that the long chain linear aliphatic alcohol family has at its centre an homologous series of increasing carbon chain length, which is associated with a consistency and predictability in the property data across the group, for the physicochemical, environmental and toxicological property data sets. In view of the structural and chemical similarities, it is considered that the results from a number of reliable developmental toxicity / teratogenicity studies on single- or multiple-constituent alcohols with appropriate chain lengths can be read across to tetracosan-1-ol. The available data have been reviewed and discussed (Veenstra G, Webb C et al., 2009). A full discussion of the Category can be found in the Human Health Alcohols C6-24 Category report (PFA, 2016).

A prenatal developmental toxicity study, performed to OECD guideline 414 and to GLP, was performed in rats dosed orally by gavage on days 6 to 15 of gestation with Alcohols C7-11 branched and linear at up to 1440 mg/kg bw/day. No maternal or developmental toxicity was seen and the top dose was therefore the NOAEL (Hellwig & Jäckh, 1997).

A prenatal developmental toxicity study, performed to OECD guideline 414 and to GLP, was performed in rats dosed orally by gavage on days 6 to 15 of gestation with octan-1-ol at 130, 650, 975 or 1300 mg/kg bw/day. A dose-dependent increase in maternal toxicity was observed, with a LOAEL of 130 mg/kg bw/day. The NOAEL for foetal toxicity was determined to be 1300 mg/kg bw/day, the highest dose tested (Hellwig & Jäckh, 1997).

In combined repeat dose and reproductive/developmental toxicity screening tests, performed to draft OECD guideline 422 and to GLP, NOAELs of 2000 mg/kg bw/day (the highest dose tested) were determined for dodecan-1-ol and for octadecan-1-ol for both maternal and developmental toxicity (Hansen, 1992a, Hansen,1992b).

Developmental toxicity studies are available for several alcohols on both rats and rabbits, and no developmental effects have been observed in either species.

Whole body inhalation studies conducted in rats with octan-1-ol, decan-1-ol, nonan-1-ol (Nelson, 1990) and hexan-1-ol (Nelson, 1989) were also available, which confirmed that the alcohols of this category do not cause any developmental effects up to the maximum achievable concentrations.

Therefore, based on the weight of evidence from other alcohols across the category, and the combined repeat dose/reproductive/developmental study withi octadecan-1-ol, t is concluded that tetracosan-1-ol is unlikely to cause developmental effects.

Discussion of trends in the Category of C6-24 linear and essentially-linear aliphatic alcohols:

There has been no indication of treatment-related effects in any of the developmental toxicity studies conducted in rats or rabbits available for any members of the chemical category. Data are available for linear and methyl-branched essentially linear alcohols with carbon chain lengths from C5 to C34.

The relatively small amounts of absorption that may occur across all common physiological routes (dermal, oral, inhalation) will be rapidly and efficiently metabolised in vivo to the corresponding fatty acid; a substance family which is exempt under REACH and which is an integral component of the conserved metabolic pathways in cells of all living organisms. These metabolic products are subsequently rapidly eliminated or may be utilised by biochemical systems in vivo, meaning that bioaccumulation does not need to be considered.

The mammalian alcohol dehydrogenase system is a group of pathways which catalyse the conversion of alcohols and aldehydes, which includes different forms of the enzymes which vary in substrate specificity. The alcohol dehydrogenases (ADHs) are divided into six classes, denoted by ADH1-ADH6. Five of the six classes of alcohol dehydrogenase have been identified in humans. One of the classes, ADH3, is the ancestral form of all mammalian ADHs, and has been traced in all living species investigated. The alcohol dehydrogenase system is considered to be able to detoxify a wide range of alcohols and aldehydes without the generation of toxic radicals. Therefore the metabolism of all category members would be expected to follow the same pathway in rats and rabbits meaning a developmental toxicity study conducted in rabbits could be expected to have the same result as a rat study.

Three category members have been tested for developmental toxicity data in rabbits. Rabbits administered docosan-1-ol by the oral route and iso-amyl alcohol by the inhalation route showed no evidence of developmental effects. Docosan-1-ol (also known as behenyl alcohol) is a linear primary alcohol with a carbon chain length of twenty-two. Iso-amyl alcohol (also known as 3-methyl-1-butanol) is a single-branched five carbon alcohol. Iso-amyl alcohol has been tested in both rats and rabbits, and no developmental effects were observed in either species. A substance known as D-002 has also been tested in both rats and rabbits, by oral route, at doses of 100, 320 and 1000 mg/kg bw/day. The test substance is a multi-constituent substance comprising linear primary alcohols with carbon chain lengths of C24, C26, C28, C30, C32 and C34. No developmental effects were observed in either species.

It is therefore considered that there are no grounds for further developmental toxicity testing in either rodent or non-rodent species.

Where data gaps exist, the gap is filled by read-across from reliable evidence within the C6-24 Alcohols Category, where possible using interpolation between at least two reliable studies using higher and lower carbon number test substances.

Developmental data for the Category

 

	CAS	CHEMICAL NAME	Study type / Species / Route / Effects	NOAEL (Ref)	Rel.*
C5	123-51-3	Isoamyl alcohol Supporting Substance	Dev.Tox Rat Inhalation: None	Mat. 2.5 mg/L Dev. 10 mg/L (Klimischet al., 1995)	2
C5	123-51-3	Isoamyl alcohol Supporting Substance	Dev. Tox Rabbit Inhalation: None	Mat. 2.5 mg/L Dev. 10 mg/L (Klimischet al., 1995))	2
C6	111-27-3	Hexan-1-ol	Dev. Tox Rat Inhalation: None	Mat/Dev. 3.5 mg/L (Nelson, 1989)	2
C6	111-27-3	Hexan-1-ol	Dev. Tox Rat Oral; None	Dev 1000 mg/kg Mat 200 mg/kg (Rodwell, 1988)	4
C8	111-87-5	Octan-1-ol	Dev Tox Rat  Inhalat’n: None	Mat/Dev.>0.4 mg/L (Nelson, 1990, 1996)	2
C8	111-87-5	Octan-1-ol	Dev. Tox Rat Oral: None	Mat 130 mg/kg       Dev 1300 mg/kg (Hellwig et al, 1997)	2
C9	143-08-8	Nonan-1-ol	Dev.Tox Rat Inhalation: None	Mat/Dev>0.15 mg/L (Nelson, 1990, 1996)	2
C10	112-30-1	Decan-1-ol	Dev.Tox Rat Inhalation: None	Mat/Dev >0.1mg/L (Nelson, 1990, 1996)	2
C11	112-42-5	Undecan-1-ol		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from dodecan-1-ol.
C12	112-53-8	Dodecan-1-ol Supporting Substance	Screen Rat Diet: None	Dev/Mat >2000 mg/kg (Hansen, 1992a)	2
C13	112-70-9	Tridecan-1-ol Supporting Substance		Not expected to be a developmental toxicant in the absence of maternal toxicity
C14	112-72-1	Tetradecan-1-ol		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances.
C15	629-76-5	Pentadecan-1-ol		Not expected to be a developmental toxicant in the absence of maternal toxicity
C16	36653-82-4	Hexadecan-1-ol		Not expected to be a developmental toxicant in the absence of maternal toxicity
C18	112-92-5	Octadecan-1-ol	Screen Rat Diet: None	Dev/Mat >2000 mg/kg (Hansen, 1992b)	2
C18	143-28-2	9-Octadecen-1-ol, (9Z)-		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on category approach and read across from structurally related substances.
C20	629-96-9	Icosanan-1-ol		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances.
C22	661-19-8	Docosan-1-ol	Dev.Tox Rat gavage: None	Mat/Dev >1000 (Iglesias, 2002b)	2
C22	661-19-8	Docosan-1-ol	Dev. Tox Rabbit Gavage; None	Mat/Dev >2000 mg/kg (Iglesias, 2002b)	2
C24	506-51-4	Tetracosan-1-ol		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances.
C8	60435-70-3	2-methylheptan-1-ol
C9	68515-81-1	Nonan-1-ol, branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from octan-1-ol.
C10	90342-32-8	Decan-1-ol, branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances as weight of evidence.
C11	128973-77-3	Undecan-1-ol, branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances as weight of evidence.
C14	90583-91-8	Tridecan-1-ol, branched and linear Supporting Substance		Not expected to be a developmental toxicant in the absence of maternal toxicity
C9-11		Alcohols, C7-9, branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances used as weight of evidence.
C9-11		Alcohols, C9-11-branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances as weight of evidence.
C11		Reaction mass of 2-methyldecan-1-ol and 2-propyloctan-1-ol and 2-ethylnonan-1-ol and 2-butylheptan-1-ol		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances as weight of evidence.
C12-13	75782-86-4	Alcohols, C12-13		Not expected to be a developmental toxicant in the absence of maternal toxicity based on read across from structurally analogous substances.
C12-13	740817-83-8	Alcohols, C12-13-branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity based on read across from structurally analogous substances.
C12-15	90604-40-3	Alcohols, C12-15-branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity based on read across from structurally analogous substances as weight of evidence.
C14-15	75782-87-5	Alcohols, C14-15		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances as weight of evidence.
C14-15		Alcohols, C14-15-branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity, based on read across from structurally analogous substances as weight of evidence.
C16-17		Alcohols, C16-17		Not expected to be a developmental toxicant in the absence of maternal toxicity
C16-17		Alcohols, C16-17 -branched and linear		Not expected to be a developmental toxicant in the absence of maternal toxicity
C16-17		Alcohols, C16-17-monobranched		Not expected to be a developmental toxicant in the absence of maternal toxicity

References:

PFA (2016). C6-24 Alcohols Category Report: Human Health. Version number:01. Peter Fisk Associates Ltd. February 2016

Veenstra G, Webb C et al., (2009) Human health risk assessment of long chain alcohols. Ecotoxicology and environmental safety 71 1016-1030

 

Justification for classification or non-classification

Based on the available data, tetracosan-1-ol does not require classification for reproductive and developmental toxicity according to Regulation (EC) No 1272/2008.