N,N-dimethyldecan-1-amide

Endpoint summary

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Effects on fertility

Description of key information

EOGRT, OECD 443, diet, rat, GLP

NOAEL Parental (F0 and F1): 12,500/6250 ppm (770,3 - 1148,1 mg/kg)
NOAEL Reproductive (F0 and F1): 12,500/6250 ppm (770,3 - 1148,1 mg/kg)
NOAEL Post-Natal Developmental: 4000/2000 ppm. (252,3 - 379,0 mg/kg)

Link to relevant study records

Reference

Endpoint:

extended one-generation reproductive toxicity - with F2 generation (Cohorts 1A, and 1B with extension)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

31 Jan 2020 - 02 June 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 443 (Extended One-Generation Reproductive Toxicity Study)

Principles of method if other than guideline:

Variation: Due to the delay in sexual maturation, mating of Cohort 1B animals and production of an F2 generation was triggered.

GLP compliance:

yes (incl. QA statement)

Justification for study design:

SPECIFICATION OF STUDY DESIGN FOR EXTENDED ONE-GENERATION REPRODUCTION TOXICITY STUDY WITH JUSTIFICATIONS [please address all points below]:

- Premating exposure duration for parental (P0) animals
: 10 weeks
- Basis for dose level selection
: see attached range finder study, Charles River Study 490131
- Inclusion/exclusion of extension of Cohort 1B : yes
- Inclusion of F2
: delayed sexual maturation in females pups of the F1 triggered F2 generation,
- Inclusion/exclusion of developmental neurotoxicity Cohorts 2A and 2B
: no, no signs of neurotoxicity from overall data
- Inclusion/exclusion of developmental immunotoxicity Cohort 3
: no, no signs of immunotoxicity from overall data
- Route of administration
: feeding, as substance leads to irritation in stomach if given in bolus

Species:

rat

Strain:

Wistar

Remarks:

Han Wistar CRL:WI (Han)

Details on species / strain selection:

Strain: Han Wistar CRL:WI (Han)
The Han Wistar rat was chosen as the animal model for this study as it is a rodent species
accepted by regulatory agencies for toxicity testing.

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: On 04 Feb 2020, 115 male (including 3 spares) and 115 female (including 3 spares) Han
Wistar CRL:WI (Han) rats were received from Charles River UK Limited, Margate, Kent,
UK
- Females (if applicable) nulliparous and non-pregnant: yes
- Age and weight at study initiation: At the initiation of dosing, the F0 Animals were 6 to 7 weeks old (males, target approximately 8 to 10 weeks) and 5 to 6 weeks old (females, approximately target 6 to
8 weeks) and weighed between 129 and 234 g (males) and 92 and 149 g (females).
- Fasting period before study: diet study
- Housing:Animals were initially socially housed 2 or 3 per cage by sex (unless reduced by mortality) in appropriately sized suspended polycarbonate cages with stainless steel grid tops and solid
bottoms.Bedding material was sterilised white wood shavings. A few days prior to mating, F0 males (and Cohort 1B males) were transferred to individual cages with solid bottoms. F0 and Cohort 1B females were transferred to these cages for mating. Mated females were transferred to individual solid bottomed cages. White paper tissue was
supplied as nesting material from Gestation Day (GD) 20. Females with un-weaned litters
were retained in this type of cage until weaning or termination. On a suitable day after completion of mating, the males were re-housed with their original cage mates. Cohort 1A and 1B were socially housed 2 or 3 per cage by sex per cage in appropriately sized suspended polycarbonate cages with stainless steel grid tops and solid bottoms.
- Diet (e.g. ad libitum): SDS VRF-1 breeder diet in ground format was provided ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: The F0 animals were allowed to acclimate to the Test Facility rodent toxicology accommodation for a period of 2 weeks before the commencement of dosing.
ENVIRONMENTAL CONDITIONS
Husbandry practices and environmental enrichment were carried out as per Test Facility
SOPs and protocol. Each batch of diet, bedding, and all environmental enrichment items were
supplied with a Certificate of Analysis. Water from the public supply is routinely analysed
for quality (including microbiological burden). Copies of the certificates for all materials and
the water analysis are retained centrally at the Test Facility. It was considered that there were
no contaminants in any of these materials that influenced the outcome of this study.
- Temperature (°C): 17 to 24°C
- Humidity (%): 32 to 78%
- Air changes (per hr): Ten or greater air changes per hour were maintained in the animal rooms
- Photoperiod (hrs dark / hrs light):12-hour light/12-hour dark cycle
There were occasions where the target environmental conditions for temperature and
humidity were not maintained. These occasions were transient and the health of the animals
was unaffected on any occasion, therefore, these excursions were considered not to impact
the outcome or integrity of the study.

Route of administration:

oral: feed

Vehicle:

other: VRF-1 Diet

Details on exposure:

DIET PREPARATION
Test item dosing formulations were prepared based on a method established at the Test
Facility (Formulation Process Document 998849-19-098) at appropriate concentrations to
meet dose level requirements. The dosing formulations were prepared at least weekly, stored
at -20oC, dispensed as required, and allowed to thaw at ambient temperature.
Any residual volumes were discarded. Details of the preparation and dispensing of the test
item have been retained in the study records
Dose formulation samples were collected for analysis (Thomson, 2020, CRL 422966).
VEHICLE
VRF-1 Diet ; common rodent diet

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Concentration Analysis

Duplicate sets of top, middle, and bottom samples (duplicate middle only for control) for
each sampling time point were sent to the appropriate laboratory for analysis. Samples for
analysis were 10 g and were taken into appropriately sized amber glass jars. Triplicate sets of
top, middle, and bottom samples (triplicate middle only for control) were collected and
maintained at the Test Facility as back-up samples. Back-up samples were 20 g and were
taken into polypropylene bags. Samples were stored at ambient room temperature.
Concentration results were considered acceptable if mean sample concentration results were
within or equal to ±10% of theoretical concentration. For homogeneity, the criteria for
acceptability was a relative standard deviation (RSD) of concentrations of <= 10% for each
group. Any residual/retained analytical samples and back-up samples were discarded
following completion of analysis.

Stability Analysis

Stability analyses performed previously in conjunction with Thomson, 2020, 422966
demonstrated that the test item is stable in the vehicle when prepared and stored under the
same conditions at concentrations bracketing those used in the present study. Stability data
have been retained in the study records for Thomson, 2020, 422966.

Duration of treatment / exposure:

The test or control items were administered ad libitum in the diet. The first day diets available
to the animals was designated as Day 1.
Treatment
F0 Males: 10 weeks prior to mating and throughout mating until termination.
F0 Females: 10 weeks prior to mating, throughout mating and gestation until at
least Lactation Day (LD) 21.
Cohort 1A: From PND 21 until the day before necropsy (at least PND 90).
Cohort 1B Males: From PND 21 until the day before necropsy (at least PND 97).
Cohort 1B Females: From PND 21 to mating, throughout mating and gestation until at
least LD 21.

Frequency of treatment:

continous

Details on study schedule:

Mating Procedure – F0 and Cohort 1B
Pairing was on a 1 male to 1 female basis. Females were housed with their allocated
co-group male partner during the evening (after 5 pm). For F0 animals, this commenced on
Study Day 71 and for Cohort 1B animals this commenced on Study Day 204 (nominally 16
weeks old).
Vaginal lavages were taken early each morning from the day of pairing until mating had
occurred and the stage of estrous observed in each vaginal lavage was recorded. The day of
detection of a copulatory plug in situ and/or of sperm in the lavage was designated GD 0.
The pairing period for each pair of animals was a maximum of 14 nights.
If evidence of mating was not observed by the end of the pairing period, the female was
separated from the male during the morning following the last night of pairing and treated as
if mating had occurred during that night. Procedures for that female continued as if it had
mated on the last night of pairing.
For each female the time taken to show a positive mating sign and the number of failed
opportunities to mate (estruses passed without a sign of mating) were evaluated.

Observations of Females and Litters - F0 and Cohort 1B Animals
The females were allowed to litter normally. Any observed difficulty or prolongation of
parturition was recorded. The day of birth of the litter (day on which first pups were born)
was designated LD 0. The duration of gestation in days was calculated.
The numbers of live and dead pups born in each litter was recorded as soon as possible after
completion of parturition on LD 0. The live pups were counted, sexed, weighed individually
on PND 1 and examined daily for the presence of milk in the stomach and for any externally
visible abnormalities daily up to and including PND 4 . On
PND 4, litter size was standardised to 8 pups, where possible 4 males and 4 females, by
culling of extra pups via random selection. Extra pups were necropsied. Where 4 males or 4 females were not available, extra pups of the opposite sex were retained to ensure a total number of 8 pups. An exception was made for Litter 2704, where the litter of 8 males and 4 females was reduced to 5 males and 3 females due to one female having an abnormal hindlimb (black/swollen) and not expected to survive. When the total number of pups in a litter on PND4 was ≤ 8 pups, no litter size adjustment occurred.
From PND 5, the total live pups were counted daily, and were sexed and examined for
abnormality again on PND 7, 14 and 21 . These pups were weighed individually.
Where practicable, any pups that were found dead or were killed during lactation were sexed
and appropriately examined as above. Any externally abnormal decedent pup was preserved
in fixative; externally normal pups were discarded.
Deficiencies in maternal care was recorded: inadequate construction or cleaning of the nest,
pups left scattered and cold, physical abuse of pups, or apparently inadequate lactation or
feeding. White paper tissue was supplied to each mother for incorporation in the nest. This
was replaced when it had become soiled.
Females which failed to produce a litter by their expected GD 24 were sent for necropsy. Any
female that had a total litter loss was sent for necropsy at the earliest appropriate time.

Pre-weaning Physical Development of F1 and F2 Pups Only
Ano-genital distance was measured on PND 1 using a calibrated caliper, the anogenital
distance was measured from the caudal margin of the anus to the caudal margin of the genital
tubercule. Measurements were recorded to the nearest 0.01 mm.
Nipple retention was assessed in males on PND 13. Nipple retention assessment was not
required on PND 21.

Weaning and Selection of F1 animals for Cohorts 1A and 1B
From each group, F1 animals were selected at random on PND 20 and identified on that day
for post-weaning assessments, nominally by selecting up to 4 males and 4 females from each
litter, where possible. Where fewer than 8 pups were weaned, the necessary additional
animals were obtained by selecting an additional pup from appropriate litters; these
appropriate litters would normally be selected arbitrarily but attention would be paid to the
retention of as wide a genetic pool as possible.
These pups were removed from their mother on PND 21 and housed in their new cages.
Pups that were not selected for post-weaning assessments (Cohorts 1A and 1B or up to
20 surplus pups per sex per group) remained with their mother until termination.

Assessment of Sexual Maturation (Cohorts 1A and 1B)
Commencing at PND 28, females were examined daily for vaginal opening. The day on
which the vagina became open was recorded, as was the body weight on that day.
Commencing at PND 35, males were examined daily for balano-preputial separation. The day
on which separation occurred was recorded, as was the body weight on that day.

Dose / conc.:

500 ppm (nominal)

Remarks:

F0 Animals (Lactation Phase), F1 Animals Cohort 1B Post-weaning (Reproductive, Lactation Phase)

Dose / conc.:

2 000 ppm (nominal)

Remarks:

F0 Animals (Lactation Phase), F1 Animals Cohort 1B Post-weaning (Reproductive, Lactation Phase)

Dose / conc.:

6 250 ppm (nominal)

Remarks:

F0 Animals (Lactation Phase), F1 Animals Cohort 1B Post-weaning (Reproductive, Lactation Phase)

Dose / conc.:

1 000 ppm (nominal)

Remarks:

F0 Animals (main Phase), F1 Animals Cohort 1A Post-weaning, F1 Animals Cohort 1B Post-weaning (Reproductive, non Lactating Phase)

Dose / conc.:

4 000 ppm (nominal)

Remarks:

F0 Animals (main Phase), F1 Animals Cohort 1A Post-weaning, F1 Animals Cohort 1B Post-weaning (Reproductive, non Lactating Phase)

Dose / conc.:

12 500 ppm (nominal)

Remarks:

F0 Animals (main Phase), F1 Animals Cohort 1A Post-weaning, F1 Animals Cohort 1B Post-weaning (Reproductive, non Lactating Phase)

No. of animals per sex per dose:

F0 = 28
F1 Cohort 1A = 20
F1 Cohort 1B = 25

Control animals:

yes, plain diet

Details on study design:

Justification of Route and Dose Levels
The oral (dietary) route of administration was selected for this study as this route has been
defined by the Sponsor as a possible route of human exposure. The highest dose
(12,500 ppm) was tested under Bain, 2020, 490131.
As food intake was expected to be considerably higher in lactating females, dietary
concentration was lowered by 50% during the lactation period to maintain similar dosage.
- Fasting period before blood sampling for clinical biochemistry: Animals were fasted overnight prior to blood sampling
- Other: Blood was collected from via orbital sinus under non-recoverable isoflurane anaesthesia or via venous collection either from the jugular vein or tail vein (without anaesthetic).
Additional blood samples were obtained (e.g. due to clotting of non-serum samples) as
required. Urine was collected in ascending animal order over 6 hours with absence of food
and presence of water.

Parental animals: Observations and examinations:

In-life Procedures, Observations, and Measurements – F0 Animals
The in-life procedures, observations and measurements listed below were performed for all
F0 animals and their litters.
Mortality/Moribundity Checks
Animals were observed twice daily, once at the start and once towards the end of the working
day throughout the study for general health/mortality and moribundity.
Clinical Observations
Cage Side Observations
Animals were observed from the cage side at least once daily, beginning Week -1.
Detailed Clinical Observations
Animals were removed from the cage and subjected to detailed clinical observations weekly,
beginning Week -1. The examinations included, but were not limited to, changes in skin, fur,
eyes, mucous membranes, palpebral closure, vocalisation, rearing, arousal, stains and
autonomic activity (lacrimation, salivation, piloerection, unusual respiratory pattern).
Changes in gait and posture, as well as the presence of clonic or tonic movements, stereotypy
or bizarre behaviour were assessed.
Body Weights
Males were weighed weekly beginning Week -1. Females were weighed weekly beginning
Week -1 until pairing for mating and then on GD 0, 7, 14 and 20 and on LD 1, 4, 7, 14 and 21. F1 Pups were weighed individually on PND 1, 4, 7, 14 and 21. A weight was also recorded on the day of scheduled necropsy.
Food Consumption
Food consumption was quantitatively measured for both sexes weekly, beginning Week -1
until pairing for mating, for the mated females on the GD periods 0 to 7, 7 to 14 and 14 to 20
and on LD periods 1 to 7, 7 to 14 and 14 to 21. Food consumption was resumed weekly for the males from Study Day 78 after mating and re-housing.
Water Consumption
Water consumption was monitored on a regular basis throughout the study by visual
inspection of the water bottles. No intergroup differences were noted.

Oestrous cyclicity (parental animals):

Estrous Cycle Monitoring
Vaginal lavages were taken early each morning and the stages of estrous observed were
recorded from 2 weeks prior to pairing (Study Day 57) until the day of detection of a
copulatory plug in situ and/or of sperm in the lavage.
Vaginal smears were examined on the morning of necropsy to determine the stage of the
estrous cycle to allow correlation with histopathology of the ovaries.

Sperm parameters (parental animals):

Sperm Evaluation – F0 and Cohort 1A Males
Computer Aided Sperm Assessment (CASA)
From all F0 and Cohort 1A males only, the right cauda epididymis was placed in 0.3% BSA
in Medium 199 as per Test Facility SOPs and the sperm was allowed to “swim out” into the
medium. An appropriate dilution of the sperm suspension was prepared and examined using a
Hamilton Thorne sperm motility analyser.
Sperm Count and Morphological Analysis
The cauda epididymis was minced and suspended. Dilutions of this sperm suspension was
counted using a haemocytometer to obtain a total sperm count which was expressed per
cauda epididymis and per gram of cauda epididymis. Optionally, the cauda epididymis was
frozen prior to assessment.
From all samples of the sperm suspension described in the preceding paragraph, a sperm
smear was prepared and stained with eosin Y solution. At least two hundred sperm per animal
was evaluated for morphological abnormalities using criteria described by Wyrobek and
Bruce (1975).
Spermatid Count
The right testis was decapsulated and homogenised. The homogenate may be sonicated to
reduce tissue debris etc., if required. The number of homogenisation resistant spermatids in
dilutions of this suspension was counted using a haemocytometer to obtain a total spermatid
count which was expressed per testis and per gram of testis. Optionally, the testis was frozen
prior to assessment.

Litter observations:

In-life Procedures, Observations, and Measurements – F1 Cohorts
The in-life procedures, observations, and measurements listed below were performed for all
applicable Cohort 1A and 1B animals, including Cohort 1B litters (i.e. F2 generation).
Mortality/Moribundity Checks
Animals were observed twice daily, once at the start and once towards the end of the working
day throughout the study for general health/mortality and moribundity.
Clinical Observations
Cage Side Observations
Animals were observed from the cage side at least once daily, beginning Week -1.
Detailed Clinical Observations
Animals were removed from the cage and subjected to detailed clinical observations weekly,
from weaning on PND 21, starting on a suitable day within one week of weaning of all litters
(Nominal Week 4).
Body Weights
Cohort 1A (both sexes) and Cohort 1B males were weighed weekly from weaning, starting
on a suitable day within one week of weaning of the majority of litters (Nominal Week 4).
Cohort 1B females were weighed weekly from weaning until pairing for mating and then on
GD 0, 7, 14 and 20 and on LD 1, 7, 14 and 21. F2 Pups were weighed individually, by sex, on
PND 1, 4, 7, 14 and 21. A weight was also recorded on the day of scheduled necropsy.
Food Consumption
Food consumption was quantitatively measured for Cohort 1A and 1B (both sexes) animals
weekly, starting on a suitable day within one week of weaning of all litters (Nominal Week 4)
and for the mated females (Cohort 1B only) on the GD periods 0 to 7, 7 to 14 and 14 to 20
and on LD periods 1 to 7, 7 to 14 and 14 to 21. Food consumption was resumed weekly for the Cohort 1B males on a suitable day after mating and re-housing.
Water Consumption
Water consumption was monitored on a regular basis throughout the study by visual
inspection of the water bottles. No intergroup differences were noted.
Estrous Cycle Monitoring
Vaginal lavages were taken early each morning and the stages of estrous observed were
recorded from the day after vaginal patency, continuing until the first confirmed estrous was
determined (from PND 75 for at least 14 consecutive days) for Cohort 1A females and from 2
weeks prior to mating until detection of a copulatory plug in situ and/or of sperm in the
lavage for Cohort 1B females.
Vaginal smears were also examined on the morning of necropsy to determine the stage of the
estrous cycle to allow correlation with histopathology of the ovaries for Cohort 1A females
only.

Postmortem examinations (parental animals):

Terminal procedures are summarised in Table 16; 17, 18 and 19 below.
Tissue Collection, Preservation and Processing are summarised in Table 21, 22, 23 and 24 below.

Postmortem examinations (offspring):

Terminal procedures are summarised in Table 16; 17, 18 and 19 below.
Tissue Collection, Preservation and Processing are summarised in Table 21, 22, 23 and 24 below.

Statistics:

STATISTICAL ANALYSIS
All results presented in the tables of the report are calculated using non-rounded values as per
the raw data rounding procedure and may not be exactly reproduced from the individual data
presented.
All statistical analyses were performed within the respective study phase, unless otherwise
noted. Numerical data collected on scheduled occasions was summarised and statistically
analysed as indicated below according to sex and occasion or by litter.
Constructed Variables
The following constructed variables were calculated and are reported.
Body weight gains: calculated against appropriate intervals
Organ weight relative to body weight: calculated against the terminal body weight
Organ weight relative to brain weight: calculated against the brain weight
Descriptive Statistical Analysis
Means, standard deviations, percentages, numbers, and/or incidences have been reported, as
appropriate by dataset.
Inferential Statistical Methods
All statistical tests were conducted at the 5% significance level. All pairwise comparisons
were conducted using two sided tests and are reported at the 1% and 5% levels, unless
otherwise noted.
The pairwise comparisons of interest are listed below:
Group 2 vs. Group 1
Group 3 vs. Group 1
Group 4 vs. Group 1
Analyses were performed according to the matrix below when possible, but excluded any
group with less than 3 observations.

Statistical Matrix
Variables for Inferential Analysis Statistical Method with Parametric/ Non-Parametric
Body Weighta X
Body Weight Gainsa X
Food Consumptiona X
Haematology Variables X
Coagulation Variables X
Clinical Chemistry Variables X
T4 X
TSH (Performed at Test Site) X
Urinalysis Variables X
Organ Weights X
Organ Weight relative to Body Weight X
Organ Weight relative to Brain Weight X
Ovarian Scoring (total number of oocytes per animal) X

Parametric/Non-Parametric
Levene’s test was used to assess the homogeneity of group variances.
The groups were compared using an overall one-way ANOVA F-te

Clinical signs:

no effects observed

Description (incidence and severity):

There were no test item related clinical signs on the study.
Clinical observations observed occurred at a low rate, didn’t follow a dose-related trend or
were of the type commonly observed in this species and were consequently considered
unrelated to administration of the test item.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

There were no test item related deaths on the study.
There was one unscheduled death of a Control animal during the course of this study. Animal
1001M (F0 Generation receiving 0 ppm) was euthanised on Day 114 due to a persistent skin
scab/lession on the right dorsal thorax which correlated microscopically with marked
ulceration.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

F0 Generation animals

There were no test item related differences in body weight or body weight gain in the F0
Generation Males during any period of the study. A statistically significant effect in body
weight change (Day 1-134) in the intermediate group (4000/2000 ppm) of F0 Generation
males was considered artefactual as it did not follow a dose-related trend.
There was a small test item related effect on the F0 Generation females of the high dose
group between Day 1 to the mating period, where body weight gain was lower (-9.8%
compared with Control).
Statistically, a difference in body weight was seen during the gestation period and up to
Lactation Day 14 for females at 12,500/6250 ppm; however the differences were minor and
therefor considered not toxicologically relevant.
There were no effects in the F0 generation females at 4000/2000 ppm or 1000/500 ppm.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

The initiation of dosing 12,500 ppm (Day 1-8) showed a significantly lower daily average
food consumption in both males (16.58 g compared with 19.26 g in the control) and females
(11.19 g compared with 13.22 g in the control). Following this, at 12,500/6250 ppm food
consumption in males and in female animals (including during gestation and lactation), was
lower than the control and (excluding lactation) frequently this difference was also
statistically significant.
In female animals prior to mating, there was evidence of a test item effect at 12500 ppm
where food consumption was lower than control. The difference was considered
toxicologically relevant as it frequently exceeded 2 grams and was statistically significant. At
4000/2000 ppm, there was no evidence of a toxicologically relevant effect during gestation or
during lactation.
At 4000/2000 ppm (males only) and 1000/500 ppm (males and females), there were no
toxicologically relevant differences in food consumption.

Food efficiency:

not examined

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

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

effects observed, non-treatment-related

Description (incidence and severity):

In F0 generation, lower levels of white blood cells (specifically lymphocytes, monocytes and
basophils) were found in male animals at 4000 ppm and 12,500 ppm. This difference
however was not seen in the male animals of Cohort 1A, therefore it was considered unlikely
to be attributable to the test item.
Differences in some parameters attained statistical significance, however they were either not
part of a dose-related trend and/or were minor and of insufficient magnitude to be considered
toxicologically relevant.

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

There were no effects on coagulation parameters following administration of the test item.
All clinical chemistry parameter of F0 where statistical significance was attained, were either
not part of a dose-related trend and/or were minor and of insufficient magnitude to be
considered toxicologically relevant.

Endocrine findings:

effects observed, non-treatment-related

Description (incidence and severity):

Concentrations of T4 were higher in male F0 Generation animals than the concurrent control
at all dose levels, Cohort 1A (male and female) animals both had higher levels of T4 at
12,500/6250 ppm. In the F1 generation (Cohort 1A) however, the control level of T4 was higher in all groups, however an increase in T4 was also apparent slight trend, with higher T4 levels at higher test item concentrations (see tabel 29; T4 concentration).There were no differences in the concentration of T4 in female animals of the F0 Generation, the unselected F1 pups culled on PND 4 or the F2 generation females.
In F0 there were no evident test item related effects on TSH levels.

Urinalysis findings:

no effects observed

Description (incidence and severity):

There were no relevant effects on urine analysis following administration of the test item.

Behaviour (functional findings):

no effects observed

Immunological findings:

no effects observed

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: neoplastic:

effects observed, non-treatment-related

Description (incidence and severity):

Test item-related microscopic findings were limited to the thyroid gland in males only.
Minimal follicular cell hypertrophy was observed in the thyroid gland of males at
12500 ppm. This correlated with the higher thyroid gland weights described above and higher
T4 levels. The low incidence of follicular cell hypertrophy at 1000 ppm and 4000 ppm was
considered insufficient evidence of a test item-related effect at these dietary concentrations.
Test item-related microscopic findings are summarised in Text Table 33.
The remaining microscopic findings observed were considered incidental, of the nature
commonly observed in this strain and age of rat, or occurred at a similar incidence in control
and treated animals,

Reproductive function: oestrous cycle:

no effects observed

Description (incidence and severity):

There were no test item related changes to the estrous cycle of female animals in any group.

Reproductive function: sperm measures:

no effects observed

Description (incidence and severity):

There were no test item related effects on sperm motility parameters (% Motile, %
Progressive motility and straight line velocity), morphological abnormalities, epididymal
sperm or testicular spermatid reserves, in either the F0 Generation or F1 (Cohort 1A) males.

Reproductive performance:

no effects observed

Description (incidence and severity):

Mating Performance, Fertility and Duration of Gestation

In both the F0 Generation and Cohort 1B animals, there were no test item related effects on
mating, fertility or pregnancy rates. Gestation length was normal in all dose groups.

Litter Survival and Survival Indices

In both the F0 Generation and Cohort 1B animals, there were no effects on litter survival,
with birth, live birth, viability (Day 0-4) and lactation (Day 4-21) indices similar over all
groups. Maternal and pup observations indicated there were no deficiencies in maternal care
at all doses tested.

Key result

Dose descriptor:

NOAEL

Effect level:

>= 12 500 ppm (nominal)

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: only adaptive and not adverse effects observed up to top dose

Remarks on result:

not determinable due to absence of adverse toxic effects

Remarks:

Reproductive NOAEL (F0 and F1): 12,500/6250 ppm

Key result

Dose descriptor:

NOAEL

Effect level:

>= 12 500 ppm (nominal)

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: only adaptive and not adverse effects observed up to top dose

Remarks on result:

not determinable due to absence of adverse toxic effects

Remarks:

Parental toxicity (F0 and F1): 12,500/6250 ppm

Clinical signs:

no effects observed

Description (incidence and severity):

There were no test item related clinical signs on the study.
Clinical observations observed occurred at a low rate, didn’t follow a dose-related trend or
were of the type commonly observed in this species and were consequently considered
unrelated to administration of the test item.

Mortality / viability:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Cohort 1A
At the high dose level (12,500/6500 ppm) there were lower body weights in Cohort 1A. At
weaning, the animals in Cohort 1A fed diet containing test item at 12,500 ppm were
significantly lighter than control (Males -14.6% and Females -16.9%). Over time the
difference in weight between the these animals and control reduced. By nominal Week 6 of
age, the difference in females was not significant (-4.9% compared with control) and by
nominal Week 10 the males no longer showed a significant difference (-5.9% compared with
control). Between weaning and the start of necropsies, Cohort 1A male and female animals
showed no overall difference in body weight gain.
There were no effects at 4000/2000 ppm or 1000/500 ppm.
Cohort 1B
A similar effect to that seen in the Cohort 1 animals was observed in the Cohort 1B. Whilst in
males statistical significance was observed until the end of the dosing period, the relative
difference was considered minor (below 10% difference from nominal Week 7), however the
overall difference in body weight gain remained statistically significant, but minor (-7.7%
between Day 1 and 120 after weaning).
In female animals no effect was observed prior to mating. Over the period of gestation (GD0-
20) body weight gain was lower in animals in the high dose group (12,500 ppm), where
animals gained 89.9 g on average compared with 114.7 g in the Control (-21.6%). This
rebounded during lactation, where body weight gains were on average higher (19.4 g
compared with 10.1 g in the control). At the end of the lactation period the difference in
body weight was minimal at 12,500/6250 ppm (-4.69% compared with control).
There were no effects at 4000/2000 ppm or 1000/500 ppm.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Cohort 1A
At 12500 ppm the food consumption post weaning was lower than control. This was most
notable over the first 3 weeks where the difference was greater than 10% and was statistically
significant. Between the 4th week and necropsy, food consumption continued to be lower at
every collection point however the magnitude of the difference was lower (<3 g per animal
per day) and no longer statistically significant. No effect was seen at 4000 ppm or 1000 ppm.
A greater difference was observed in female animals at this dose level where all data points
showed lower food consumption that was >10% and statistically significant. Evidence of an
effect was also seen at 4000 ppm where food consumption was consistently lower than the
control, however the difference was more modest (typically between 5-10% and not
statistically significant).
No effect was seen in males at 4000 ppm or in male and females at 1000 ppm.
Cohort 1B
A food consumption pattern similar to Cohort 1A was observed, with male animals having
sustained lower food consumption at 12,500/6250 ppm for the whole dosing period (weaning
to necropsy). Female animals also had a lower food consumption from weaning at
12,500/6250 ppm, most notable at the end of gestation where food consumption was 23.3%
lower than the control. In female animals a more modestly lower food consumption was also
observed at 4000 ppm. In female animals during lactation, the difference in food
consumption was only toxicologically relevant at 6250 ppm.
No effect was seen in males at 4000 ppm or in male and females at 1000 ppm.

Food efficiency:

not specified

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

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Description (incidence and severity):

Differences in some parameters attained statistical significance, however they were either not
part of a dose-related trend and/or were minor and of insufficient magnitude to be considered
toxicologically relevant.

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

In Cohort 1A the male animals only, there was a dose-related trend was observed in the bile
acids (1.53x, 1.98x and 2.54x control at 1000, 4000 and 12,500 ppm, respectively), however
there was no equivalent finding in the F0 generation.
In female animals in Cohort 1A there was a small increase in cholesterol at 4000 ppm (1.35X
control) and 12,500 ppm (1.45x control). There was no effect in the males of cohort 1A or the
females of the F0 generation. Therefore, this finding is considered to be incidental.
For all other parameters differences where statistical significance was attained, were either
not part of a dose-related trend and/or were minor and of insufficient magnitude to be
considered toxicologically relevant.

Urinalysis findings:

no effects observed

Description (incidence and severity):

There were no relevant effects on urine analysis following administration of the test item.

Sexual maturation:

effects observed, non-treatment-related

Description (incidence and severity):

A delay in sexual maturity was evident in female animals at 12,500/6250 ppm in both
Cohort 1A (average 38.5 days compared to 32.3 days in the concurrent control) and
Cohort 1B (average of 37.7 days compared with 33.4 in the concurrent control).
Notwithstanding this, the number of days after vaginal opening that the first estrous was
detected was similar over all treatment groups.
Male animals at 12,500/6250 also showed a slightly longer time to reach sexual maturity,
(although the difference was smaller than in females). The difference was seen in Cohort 1A
(42.9 days vs 41.1 in the Control) and Cohort 1B (43.9 days vs 41.0 days in the Control).
These differences can be attributed to the decreased body weight development in the high
dose group. Mean body weight at the time of sexual maturity were comparable in males and
females and also within the historical control range of the rat strain used. See attached pdf for historical control data.

Anogenital distance (AGD):

no effects observed

Description (incidence and severity):

There were no test item effects on anogenital distance.

Nipple retention in male pups:

no effects observed

Description (incidence and severity):

There were no male pups with retained nipples on PND 13.

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

Cohort 1A - Test item-related Organ Weight Differences:
Test item-related organ weight differences were noted in the liver. Liver weights were higher
than controls at ≥ 4000 ppm in males and at 12500 ppm in females. See Table 31.
Mandibular lymph node weights were higher in females at 12500 ppm. Given that there was
no microscopic correlate and only females were affected, this was also considered to be
unrelated to the administration of the test item.
Other organ weight differences, including those with statistical significance, were also
considered not to be test item-related as they had no microscopic correlate and were often a
reflection of lower mean terminal body weights in the affected group.
Cohort 1B - Test item-related Organ Weight Differences:
There were no test item-related organ weight differences. Liver weights were higher than
controls at ≥ 1000 ppm in males and at 12500 ppm in females. See Table 32.
Other organ weight differences, including those with statistical significance, were also considered not to be test item-related because the organs had no microscopic correlate in F1 Cohort 1A animals and, for the most part, were considered to be a reflection of lower mean terminal body weight.
F1 Unselected Pups (PND 22-24)
There were no test item-related organ weight differences.
Spleen weight was lower than controls in females at 12500 ppm. These tissues were not examined microscopically. However, given that only one sex was affected and the lack of correlating microscopic findings in F0 and F1 Cohort 1A animals, this was considered not to be test item-related and was considered most likely a reflection of the lower mean terminal body weight in this group.

Gross pathological findings:

no effects observed

Description (incidence and severity):

There were no test item-related gross findings in the F0 Generation, F1 animals (Cohort 1A,
Cohort 1B or unselected pups on PND 22-24 used for thyroid hormone analysis) or the F2
pups (on PND 22).
All gross findings observed were considered incidental, of the nature commonly observed in
this strain and age of rat, or occurred at a similar incidence in control and treated animals,
and, therefore, were considered not to be related to the test item.

Histopathological findings:

no effects observed

Description (incidence and severity):

Cohort 1A: There were no test item-related microscopic findings.
Microscopic findings were considered incidental, of the nature commonly observed in this
strain and age of rat or occurred at a similar incidence in control and treated animals, and,
therefore, were considered not to be related to the administration of the test item.
F1 Unselected Pups (PND 22-24): Only the mammary gland was examined microscopically. There were no microscopic abnormalities evident in the tissue examined to support the presence of a test item-related effect.

Other effects:

effects observed, non-treatment-related

Description (incidence and severity):

Thyroxine (T4)
In the F1 generation (Cohort 1A) however, the control level of T4 was higher in all groups,
however an increase in T4 was also apparent trend, with higher T4 levels at higher test item
concentrations. There were no differences in the concentration of T4 in female animals of the F0 Generation, the unselected F1 pups culled on PND 4 or the F2 generation females. See Table 29 below
Thyroid Stimulating Hormone (TSH)
There were no evident test item related effects on TSH levels. It was noted that in Cohort 1A
males levels of TSH were notably higher in all groups, including control. There was no test
item effect however this elevation was similar to the higher levels of T4 observed in
Cohort 1A.

Behaviour (functional findings):

not examined

Developmental immunotoxicity:

not examined

The delayed sexual maturation in females pups of the F1 generation is considered to be a
consequence of delayed body weight development. The body weights at the time of sexual
maturity were within the historical control range. Nevertheless, this finding was a trigger for
a second mating, which showed that fertility parameters and maternal performance were
unaffected by test item as the Cohort 1B animals went on to produce normal litters. The
viability and survival of the F2 generation was also unaffected by the test item.

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

4 000 ppm (nominal)

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

sexual maturation

body weight and weight gain

food consumption and compound intake

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Overall, females in gestation and young animals (F1 and F2 pups) exposed to the test item in
the high dose group (12,500/6250 ppm) showed a lower body weight gain than control. This
effect was seen to be reversible over time. No relevant body weight differences were seen in
the intermediate (4000/2000 ppm) or low (1000/500 ppm) dose groups. Pups in both F1 (litters of the F0 Generation) and F2 (Cohort 1B litters) showed reduced preweaning
body weight gains at the high dose level (administered at 6250 ppm during lactation)
than the controls. The greatest effects were observed at the end of lactation (LD 21) where
the difference exceeded 10% as follows: see table 28

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 examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

not examined

Anogenital distance (AGD):

no effects observed

Nipple retention in male pups:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Description (incidence and severity):

F2 Unselected Pups (PND 22)
There were no test item-related organ weight differences.
Compared to controls, there were differences in brain, spleen and thymus weight in males and
brain weight in females at 12500 ppm. These tissues were not examined microscopically.
However, they were considered not to be test item-related because there was no microscopic
correlate in other cohorts examined and, for the most part, were considered a reflection of
lower mean terminal body weight in this group.

Gross pathological findings:

no effects observed

Description (incidence and severity):

There were no test item-related gross findings in the F0 Generation, F1 animals (Cohort 1A,
Cohort 1B or unselected pups on PND 22-24 used for thyroid hormone analysis) or the F2
pups (on PND 22).

Histopathological findings:

not examined

Other effects:

effects observed, treatment-related

Description (incidence and severity):

Thyroxine (T4)
In the F1 generation (Cohort 1A) however, the control level of T4 was higher in all groups,
however an increase in T4 was also apparent trend, with higher T4 levels at higher test item
concentrations. There were no differences in the concentration of T4 in female animals of the F0 Generation, the unselected F1 pups culled on PND 4 or the F2 generation females. See Table 29 below
Thyroid Stimulating Hormone (TSH)
There were no evident test item related effects on TSH levels. It was noted that in Cohort 1A
males levels of TSH were notably higher in all groups, including control. There was no test
item effect however this elevation was similar to the higher levels of T4 observed in
Cohort 1A.

Behaviour (functional findings):

not examined

Developmental immunotoxicity:

not examined

The delayed sexual maturation in females pups of the F1 generation is considered to be a
consequence of delayed body weight development. The body weights at the time of sexual
maturity were within the historical control range. Nevertheless, this finding was a trigger for
a second mating, which showed that fertility parameters and maternal performance were
unaffected by test item as the Cohort 1B animals went on to produce normal litters. The
viability and survival of the F2 generation was also unaffected by the test item.

Key result

Reproductive effects observed:

no

Table 29
Thyroxine (T4) Concentrations (ng/mL)

Generation/Sex	Group 1 (0 ppm)	Group 2 (1000/500 ppm)	Group 3 (4000/2000 ppm)	Group 4 (12,500/6250 ppm)
F0 Generation – Males	39.86	51.30 (+29%)	47.08 (+18%)	54.35% (+36%)
F1 Unselected – Males (PND 22-24)	33.44	32.12 (-4%)	34.46 (+3%)	41.90 (+25%)
F1 Surplus – Females (PND 21-24)	34.11	31.31 (-8%)	34.21 (0%)	40.02 (+17%)
Cohort 1A – Males	49.44	52.14 (+5%)	57.18 (+16%)	61.73 (+25%)
Cohort 1A – Female	34.70	36.64 (+6%)	37.61 (+8%)	41.64 (+20%)
F2 Generation – Males (PND 22)	31.94	33.45 (+5%)	34.13 (+7%)	43.09 (+35%)

Table 30
Summary Group Mean Organ Weight Data – Scheduled Euthanasia F0 Males

Males
Group	1	2	3	4
Nominal Dietary Concentration (ppm)	0	1000	4000	12500
No. animals per group	27	28	28	28
Gland, Thyroid (No. weighed)	(27)	(28)	(28)	(28)
Absolute value (g)	0.02274	0.02366	0.02564	0.02720^**
% of body weight	0.00516	0.00526	0.00564	0.00635^**
% of brain weight	1.08740	1.11478	1.22262	1.28982^**
Liver (No. weighed)	(27)	(28)	(28)	(28)
Absolute value	12.8133	13.9206	14.7870^**	15.0387^**
% of body weight	2.89638	3.10046^*	3.23424^**	3.49326^**
% of brain weight	612.20483	656.93197	704.97523^**	713.01143^**
Females
Group	1	2	3	4
Nominal Dietary Concentration (ppm)	0	1000	4000	12500
No. animals per group	28	28	28	28
Gland, Thyroid (No. weighed)	(28)	(28)	(28)	(28)
Absolute value (g)	0.02216	0.02136	0.02241	0.02263
% of body weight	0.00886	0.00843	0.00900	0.00941
% of brain weight	1.17154	1.11777	1.17373	1.20291
Liver (No. weighed)	(28)	(28)	(28)	(28)
Absolute value	12.4046	12.9997	13.0981	14.2145^**
% of body weight	4.93420	5.11378	5.26092	5.87962^**
% of brain weight	653.95826	680.25642	686.43030	754.40465^**

Anova & Dunnett: ^* = p ≤ 0.05; ^** = p ≤ 0.01

Table 33
Summary Test Item-related Microscopic Findings – Scheduled Euthanasia F0 Males

	Males
Group	1	2	3	4
Nominal Dietary Concentration (ppm)	0	1000	4000	12500
No. animals examined	27	28	28	28
Gland, Thyroid (No. Examined)	(27)	(28)	(28)	(28)
Hypertrophy, follicular cell, minimal	0	2	4	9

Table 31
Summary Group Mean Organ Weight Data – Scheduled Euthanasia F1 Cohort 1A

Males
Group	1	2	3	4
Nominal Dietary Concentration (ppm)	0	1000	4000	12500
No. animals per group	20	20	20	20
Liver (No. weighed)	(20)	(20)	(20)	(20)
Absolute value	13.5999	13.5419	14.5869	14.9228^*
% of body weight	3.65022	3.67897	3.89964^*	4.32421^**
% of brain weight	666.66881	653.65769	710.89335	747.92891^**
Females
Group	1	2	3	4
Nominal Dietary Concentration (ppm)	0	1000	4000	12500
No. animals per group	20	20	20	20
Liver (No. weighed)	(20)	(20)	(20)	(20)
Absolute value	8.1019	8.0103	8.2154	8.1057
% of body weight	3.90270	3.76515	3.99996	4.20932^*
% of brain weight	430.71382	423.49596	436.18854	441.05572

Anova & Dunnett: ^* = p ≤ 0.05; ^** = p ≤ 0.01

 

Table 32
Summary Group Mean Organ Weight Data – Scheduled Euthanasia F1 Cohort 1B

Males
Group	1	2	3	4
Nominal Dietary Concentration (ppm)	0	1000	4000	12500
No. animals per group	25	25	25	25
Liver (No. weighed)	(25)	(25)	(25)	(25)
Absolute value	15.1339	15.9292	16.6796^*	16.1066
% of body weight	3.33411	3.53799^*	3.69083^**	3.88985^**
% of brain weight	725.86628	748.24734	789.19268	771.03969
Females
Group	1	2	3	4
Nominal Dietary Concentration (ppm)	0	1000	4000	12500
No. animals per group	25	25	25	25
Liver (No. weighed)	(25)	(25)	(25)	(25)
Absolute value	14.1927	14.4609	14.3412	15.0251
% of body weight	5.15096	5.26507	5.22560	5.73997^**
% of brain weight	736.76337	750.11143	744.52945	789.93815

Anova & Dunnett: ^* = p ≤ 0.05; ^** = p ≤ 0.01

Conclusions:

Parental toxicity (F0 and F1): 12,500/6250 ppm (770,3 - 1148,1 mg/kg)
Reproductive NOAEL (F0 and F1): 12,500/6250 ppm (770,3 - 1148,1 mg/kg)
Post-Natal Developmental NOAEL: 4000/2000 ppm. (252,3 - 379,0 mg/kg)

Executive summary:

The objective of this study was to determine the potential toxicity of N, N‑Dimethyldecan‑1‑amide, when given by oral dietary administration to rats to assess the reproductive function in adult animals and their offspring according to OECD 443 (BASF SE 2021). This study was designed to provide an evaluation of the pre and postnatal effects of chemicals on development as well as a thorough evaluation of systemic toxicity in pregnant females, lactating females, young and adult offspring. Detailed examination of key developmental endpoints, such as offspring viability, neonatal health, developmental status at birth, and physical and functional development until adulthood, was expected to identify specific target organs in the offspring. In addition, the study provided information about the effects of the test item on the integrity and performance of the adult male and female reproductive systems.

The study design was as follows:

Text Table 1
Experimental Design – F0 Animals

Group No.	Treatment	Nominal Dietary Concentration (ppm)		Formulated Dietary Concentration (ppm)^a		Number of Animals
		Main Phase	Lactation Phase^b	Main Phase	Lactation Phase^b	M	F
1	Control	0	0	0	0	28	28
2	N-N-dimethyldecan- 1-amide	1000	500	1020	510	28	28
3		4000	2000	4080	2040	28	28
4		12500	6250	12750	6375	28	28
M=Males; F=Females ^aCorrection factor of 1.02 applied. ^bDuring the lactation phase, as the maternal food consumption increased, the dietary concentration for females only was lowered by 50%.

Text Table 2
Experimental Design – F1 Animals Cohort 1A Post-weaning

Group No.	Treatment	Nominal Dietary Concentration (ppm)	Formulated Dietary Concentration (ppm)^a	Number of Animals
				M	F
1	Control	0	0	20	20
2	N-N-dimethyldecan- 1-amide	1000	1020	20	20
3		4000	4080	20	20
4		12500	12750	20	20
M=Males; F=Females ^aCorrection factor of 1.02 applied.

Text Table 3
Experimental Design – F1 Animals Cohort 1B Post-weaning (Reproductive)

Group No.	Treatment	Nominal Dietary Concentration (ppm)		Formulated Dietary Concentration (ppm)^a		Number of Animals
		Main Phase	Lactation Phase^b	Main Phase	Lactation Phase^b	M	F
1	Control	0	0	0	0	25	25
2	N-N-dimethyldecan- 1-amide	1000	500	1020	510	25	25
3		4000	2000	4080	2040	25	25
4		12500	6250	12750	6375	25	25
M=Males; F=Females ^aCorrection factor of 1.02 applied. ^bDuring the lactation phase, as the maternal food consumption increased, the dietary concentration for females only was lowered by 50%.

The following parameters and end points were evaluated in this study:  clinical observations, body weights, food consumption, estrous cycles, estimated achieved doses, mating performance and fertility indices (F0 and Cohort 1B), duration of gestation and overall litter performance (F0 and Cohort 1B), F1 and F2 survival indices, litter and pup weights, pre- weaning physical development of F1 and F2 pups, assessments of sexual maturation of F1 animals (Cohorts 1A and 1B), clinical pathology parameters (haematology, coagulation, clinical chemistry and urinalysis [F0 and Cohort 1A]), thyroid stimulation hormone (TSH) and thyroxine (T4) analysis, gross necropsy findings, organ weights, immunophenotyping analysis (Cohort 1A), sperm evaluation (F0 and Cohort 1A males), ovarian follicle counts (Cohort 1A) and histopathological examinations.

Administration of the test item via the diet at 12,500/6250 ppm was associated with toxicity as evidenced by lower food consumption in males and females at 12,500/6250 ppm and in female animals only at 4000/2000 ppm. Effects on development were observed with a lower in body weight gain during lactation at the high dose group (6250 ppm).  In the high dose (12,500/6250 ppm) there was also evidence of a delayed sexual maturation in the F1 generation pups (Cohort 1A and Cohort 1B pups) average time to vaginal opening was 38.5 days compared to 32.3 days (Cohort 1A) and 37.7 days compared with 33.4 days (Cohort 1B). This delay is considered to be a consequence of delayed body weight development. The body weights at the time of sexual maturity were within the historical control range. The delay in vaginal opening did not adversely affect the time to the first estrous. Due to the delay in sexual maturation, mating of Cohort 1B animals and production of an F2 generation was triggered. This evaluation demonstrated that despite the delay in sexual maturation, there were no adverse changes on the fertility and maternal performance of the Cohort 1B animals, nor was the viability and survival of the F2 generation affected.

Adaptive changes in the form of follicular cell hypertrophy, were observed in the thyroids of rats following administration of the test item in the diet.

In conclusion, administration of N,N-Dimethyldecan-1-amide by diet was tolerated in male and female rats at doses up to 12,500/6250 ppm.  Toxicity was manifest through lower food consumption and lower body weight gains, including in the offspring of rats administered N,N‑Dimethyldecan-1-amide at 12,500/6250 ppm as well as delays in sexual maturation in female offspring as the consequence of lower body weights. However these delays in sexual maturation did not go on to affect the fertility or maternal performance of the animals.

The administration of N, N-dimethyldecan-1-amide was associated with effects on the thyroid gland of F0 Generation males only at 12,500 ppm, which was not considered to be adaptive and not adverse based on the minimal grade of severity and incidence.

Based on the results of this extended one generation reproductive toxicity study (Cohort 1), the following no-observed-adverse-effect level (NOAEL) of N,N-Dimethyldecan-1-amide were established:

Parental toxicity (F₀ and F₁):  12,500/6250 ppm
Reproductive NOAEL (F₀ and F₁):  12,500/6250 ppm
Post-Natal Developmental NOAEL:  4000/2000 ppm.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

770 mg/kg bw/day

Study duration:

subchronic

Experimental exposure time per week (hours/week):

24

Species:

rat

Quality of whole database:

Reliability Klimisch 1

Additional information

There is valid information available investigating the effects on fertily of N,N-dimethyldecanamide (CAS 14433 -76 -2).

 

EOGRT:

The objective of this study was to determine the potential toxicity of N, N‑Dimethyldecan‑1‑amide, when given by oral dietary administration to rats to assess the reproductive function in adult animals and their offspring according to OECD 443 (BASF SE 2021). This study was designed to provide an evaluation of the pre and postnatal effects of chemicals on development as well as a thorough evaluation of systemic toxicity in pregnant females, lactating females, young and adult offspring. Detailed examination of key developmental endpoints, such as offspring viability, neonatal health, developmental status at birth, and physical and functional development until adulthood, was expected to identify specific target organs in the offspring. In addition, the study provided information about the effects of the test item on the integrity and performance of the adult male and female reproductive systems.

The study design was as follows:

Text Table 1
Experimental Design – F0 Animals

Group No.	Treatment	Nominal Dietary Concentration (ppm)		Formulated Dietary Concentration (ppm)^a		Number of Animals
		Main Phase	Lactation Phase^b	Main Phase	Lactation Phase^b	M	F
1	Control	0	0	0	0	28	28
2	N-N-dimethyldecan- 1-amide	1000	500	1020	510	28	28
3		4000	2000	4080	2040	28	28
4		12500	6250	12750	6375	28	28
M=Males; F=Females ^aCorrection factor of 1.02 applied. ^bDuring the lactation phase, as the maternal food consumption increased, the dietary concentration for females only was lowered by 50%.

Text Table 2
Experimental Design – F1 Animals Cohort 1A Post-weaning

Group No.	Treatment	Nominal Dietary Concentration (ppm)	Formulated Dietary Concentration (ppm)^a	Number of Animals
				M	F
1	Control	0	0	20	20
2	N-N-dimethyldecan- 1-amide	1000	1020	20	20
3		4000	4080	20	20
4		12500	12750	20	20
M=Males; F=Females ^aCorrection factor of 1.02 applied.

Text Table 3
Experimental Design – F1 Animals Cohort 1B Post-weaning (Reproductive)

Group No.	Treatment	Nominal Dietary Concentration (ppm)		Formulated Dietary Concentration (ppm)^a		Number of Animals
		Main Phase	Lactation Phase^b	Main Phase	Lactation Phase^b	M	F
1	Control	0	0	0	0	25	25
2	N-N-dimethyldecan- 1-amide	1000	500	1020	510	25	25
3		4000	2000	4080	2040	25	25
4		12500	6250	12750	6375	25	25
M=Males; F=Females ^aCorrection factor of 1.02 applied. ^bDuring the lactation phase, as the maternal food consumption increased, the dietary concentration for females only was lowered by 50%.

The following parameters and end points were evaluated in this study:  clinical observations, body weights, food consumption, estrous cycles, estimated achieved doses, mating performance and fertility indices (F0 and Cohort 1B), duration of gestation and overall litter performance (F0 and Cohort 1B), F1 and F2 survival indices, litter and pup weights, pre- weaning physical development of F1 and F2 pups, assessments of sexual maturation of F1 animals (Cohorts 1A and 1B), clinical pathology parameters (haematology, coagulation, clinical chemistry and urinalysis [F0 and Cohort 1A]), thyroid stimulation hormone (TSH) and thyroxine (T4) analysis, gross necropsy findings, organ weights, immunophenotyping analysis (Cohort 1A), sperm evaluation (F0 and Cohort 1A males), ovarian follicle counts (Cohort 1A) and histopathological examinations.

Administration of the test item via the diet at 12,500/6250 ppm was associated with toxicity as evidenced by lower food consumption in males and females at 12,500/6250 ppm and in female animals only at 4000/2000 ppm. Effects on development were observed with a lower in body weight gain during lactation at the high dose group (6250 ppm).  In the high dose (12,500/6250 ppm) there was also evidence of a delayed sexual maturation in the F1 generation pups (Cohort 1A and Cohort 1B pups) average time to vaginal opening was 38.5 days compared to 32.3 days (Cohort 1A) and 37.7 days compared with 33.4 days (Cohort 1B). This delay is considered to be a consequence of delayed body weight development. The body weights at the time of sexual maturity were within the historical control range. The delay in vaginal opening did not adversely affect the time to the first estrous. Due to the delay in sexual maturation, mating of Cohort 1B animals and production of an F2 generation was triggered. This evaluation demonstrated that despite the delay in sexual maturation, there were no adverse changes on the fertility and maternal performance of the Cohort 1B animals, nor was the viability and survival of the F2 generation affected.

Adaptive changes in the form of follicular cell hypertrophy, were observed in the thyroids of rats following administration of the test item in the diet.

In conclusion, administration of N,N-Dimethyldecan-1-amide by diet was tolerated in male and female rats at doses up to 12,500/6250 ppm.  Toxicity was manifest through lower food consumption and lower body weight gains, including in the offspring of rats administered N,N‑Dimethyldecan-1-amide at 12,500/6250 ppm as well as delays in sexual maturation in female offspring as the consequence of lower body weights. However these delays in sexual maturation did not go on to affect the fertility or maternal performance of the animals.

The administration of N, N-dimethyldecan-1-amide was associated with effects on the thyroid gland of F0 Generation males only at 12,500 ppm, which was not considered to be adaptive and not adverse based on the minimal grade of severity and incidence.

Based on the results of this extended one generation reproductive toxicity study (Cohort 1), the following no-observed-adverse-effect level (NOAEL) of N,N-Dimethyldecan-1-amide were established:

Parental toxicity (F₀ and F₁):  12,500/6250 ppm
Reproductive NOAEL (F₀ and F₁):  12,500/6250 ppm
Post-Natal Developmental NOAEL:  4000/2000 ppm.

 

Key study assignment:

There is one cruxial study available which is used as key study for this endpoint.

 

Effects on developmental toxicity

Description of key information

- oral, rat, gavage, 6-15 post coitum, mixture of N,N-dimethyl-decanamide and N,N-dimethyl-octanamide,

OECD 414: NOAEL (maternal) 50 mg/kg bw/d; NOAEL (fetal) 150 mg/kg bw/d; no teratogenic potential up to 450 mg/kg bw/d. (RCC 1991)

- oral, rabbit, gavage, 6-18 post coitum, mixture of N,N-dimethyl-decanamide and N,N-dimethyl-octanamide,

OECD 414: NOAEL (maternal) 300 mg/kg bw/d; NOAEL (fetal) 1000 mg/kg bw/d; no teratogenic potential (Bayer 1991)

Link to relevant study records

Reference

Reference 1

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Aug - Sep 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Version / remarks:

May 12, 1981

GLP compliance:

yes

Limit test:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Lot/batch No.of test material: 903069
- Expiration date of the lot/batch: November 17, 1990

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature, in the dark
- Stability of the test substance in the solvent/vehicle: at least 2 hours at room temperature

Species:

rabbit

Strain:

Chinchilla

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. Karl Thomae GmbH / Birkendorferstrasse 65 / D-W-7950 Biberach / Riss
- Age at pairing: between 4 and 6 months
- Weight at study initiation: 2810 - 4825 grams (day 0 post coitum)
- Housing: individually
- Diet: ad libitum; Pelleted standard Kliba 341 rabbit maintenance diet ("Kliba" / Klingentalmuehle AG / CH 4303 Kaiseraugst / Switzerland)
- Water: Tap water was available ad libitum by an automatic system.
- Acclimation period: minimum of 7 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3°C
- Humidity (%): 40 - 70%
- Air changes (per hr): 10-15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours artificial fluorescent light/12 hours dark with background music played at a centrally defined low volume for at least 8 hours during the light period.

Route of administration:

oral: gavage

Vehicle:

other: Bi-distilled water with 0.5 % Cremophor (BASF)

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
The mixtures of the test article and vehicle were prepared daily before administration. The test article was weighed into a glass beaker on a tared precision balance (Mettler PE 360) and the vehicle added (w/w). The mixtures were prepared using a homogenizer. During the daily administration period,
homogeneity was maintained using a magnetic stirrer.

VEHICLE
- Concentration in vehicle: 25 mg/ml, 75 mg/ml, 250 mg/ml
- Amount of vehicle (if gavage): adjusted to a total application volumen 4ml/kg bw

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Photometric analytical verification (UV/Vis)
Concentrations (25, 75, 250 mg/ml) and stability in bidestilled water with 0.5% Cremophor was verified.
Result: Recovery between 95.3 and 101.0%
Homogeneity varies from -5 to + 3%

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: 1/1
until copulation was observed. The day of mating was designated as day 0 post coitum.

Duration of treatment / exposure:

- The test article was administered orally, by gavage, once daily in the morning from day 6 through to day 18 post coitum.
- Dose volume: 4 ml/kg body weight (daily adjustment of the individual volume to the actual body weight)

Frequency of treatment:

daily from day 6 through day 18 post coitum

Duration of test:

28 days (from successful mating to termination, excluding acclimatisation etc)

Dose / conc.:

100 mg/kg bw/day (nominal)

Dose / conc.:

300 mg/kg bw/day (nominal)

Dose / conc.:

1 000 mg/kg bw/day (nominal)

No. of animals per sex per dose:

16 mated female rabbits

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Dosages were based on the results of the dose range-finding study.

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily
- Cage side observations checked: mortalities, signs of reactions of treatment and/or symptoms of ill health

DETAILED CLINICAL OBSERVATIONS: no

BODY WEIGHT: Yes
- Time schedule for examinations: daily from day 0 until day 28 post coitum

FOOD CONSUMPTION: Yes
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Time schedule: days 0-6, 6-11, 11-15, 15-19, 19-24 and 24-28 post coitum

WATER CONSUMPTION: No

POST-MORTEM EXAMINATIONS: yes
- Sacrifice on day 28 post coitum
- Post mortem examination, including gross macroscopic examination of all internal organs, with emphasis on the uterus, uterine contents, position of fetuses in the uterus and number of corpora lutea

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 (embryonic resoption): Yes
- Number of late resorptions (fetal resorption): Yes
- Number of Pre-Implantation loss: yes
- Number of Post-Implantation loss: yes

Fetal examinations:

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

Statistics:

- Univariate one-way analysis of variance was used to assess the significance of intergroup differences.
- If the variables could be assumed to follow a normal distribution, the Dunnett-test (many-one t-test), based on a pooled variance estimate, was applied for the comparison between the treated groups and the control group.
- The Steel-test (many-one rank test) was applied when the data could not be assumed to follow a normal distribution.
- Fisher's Exact test for 2x2 tables was applied if the variables could be dichotomized without loss of information.

Indices:

see "Any other information on materials and methods incl. tables"

Historical control data:

Historical data of Chinchilla Rabbits (Hybrids, SPF Quality) from 1987, 1988 and 1989:
- Reproduction data of dams
- Spontaneous abnormal findings of fetuses (external, vsceral or skeletal examination)
- Skeletal examination of fetuses (stage of development) on fetus basis or on litter basis

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

- group 4 (1000 mg/kg): in 1 female slight dyspnoea and ventral recumbency a few hours prior to death on day 12 post coitum and 1 female with dyspnoea on day 9 post coitum during 5 hours

These isolated findings were considered to be incidental and not test article related effects.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

- group 2 (100 mg/kg): 3 females died during the dosing period; 1 on day 7 post coitum (2nd day of dosing) and 1 on day 15 post coitum (10th day of dosing) to intubation errors, 1 on day 12 post coitum (7th day of dosing) spontaneously without any signs of toxic effects
- group 3 (300 mg/kg): 1 female was found dead in the morning of day 28 post coitum (day of Caesarean Section, ten days after the last dosing) without any previous signs of toxic effects.
- group 4 (1000 mg/kg): 1 female died on day 12 post coitum (7th day of dosing) without any previous signs of toxic effects.

These Isolated cases of spontaneous deaths In any dose groups were considered to be incidental because no relation to the number of administrations or to the dosages was evident.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

- group 4 (1000 mg/kg): slightly reduced mean body weight gain during the dosing period (in particular between days 6 and 11 post coitum (1st and 6th day of dosing))

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

- group 4 (1000 mg/kg): reduction in food consumption (-21.2% compared to vehicle control) during the dosing period (days 6 to 19 post coitum), statistically significant between days 11-15 post coitum

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:

no effects observed

Gross pathological findings:

no effects observed

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

no effects observed

Number of abortions:

no effects observed

Pre- and post-implantation loss:

no effects observed

Description (incidence and severity):

- the total post-implantation loss in two females of group 3 (300 mg/kg) was considered to be incidental, because no female with total post-implantation loss was evident in group 4 (1000 mg/kg)

Total litter losses by resorption:

no effects observed

Early or late resorptions:

no effects observed

Dead fetuses:

no effects observed

Changes in pregnancy duration:

not specified

Description (incidence and severity):

Migrated Data from removed field(s)
Field "Effects on pregnancy duration" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsMaternalAnimals.MaternalDevelopmentalToxicity.EffectsOnPregnancyDuration): not specified

Changes in number of pregnant:

no effects observed

Other effects:

no effects observed

Dose descriptor:

NOAEL

Remarks:

general toxicity

Effect level:

300 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

body weight and weight gain

food consumption and compound intake

Abnormalities:

no effects observed

Fetal body weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

- groups 1 (vehicle control) and 3 (300 mg/kg): 2 runts (body weight <19.0 g)
Migrated Data from removed field(s)
Field "Fetal/pup body weight changes" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.FetalPupBodyWeightChanges): effects observed, non-treatment-related
Field "Description (incidence and severity)" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.DescriptionIncidenceAndSeverityFetalPupBodyWeightChanges): - groups 1 (vehicle control) and 3 (300 mg/kg): 2 runts (body weight <19.0 g)

Reduction in number of live offspring:

no effects observed

Description (incidence and severity):

no dead fetuses

Changes in sex ratio:

no effects observed

Changes in litter size and weights:

not examined

Changes in postnatal survival:

not examined

External malformations:

no effects observed

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

1/158 fetuses in 1/16 litters in group 1 (vehicle control);
2/145 fetuses in 2/14 litters in group 2 (100 mg/kg);
3/120 fetuses in 3/12 litters in group 3 (300 mg/kg);
1/147 fetus in 1/15 litters in group 4 (1000 mg/kg).

The findings noted were: thoracic vertebral bodies and/or arches (hemicentric, missing or fused), sternebrae abnormally ossified and/or fused, rib(s) bifurcated or fused and caudal vertebrae hemicentric or bipartite.

The types and the incidences of the abnormal findings noted did not indicate test article specific effects.

Visceral malformations:

effects observed, non-treatment-related

Description (incidence and severity):

- group 2 (100 mg/kg): 1/145 fetuses with dilated aorta and missing arch of aorta
- group 3 (300 mg/kg): 1/120 fetuses with hemidiaphragm and 1 fetus with oval foramen in the diaphragm
- group 4 (1000 mg/kg): 1/147 fetuses with hydronephrosis (both kidneys)

These isolated abnormal findings noted did not indicate an association with administration of the test article.

Other effects:

no effects observed

Dose descriptor:

NOAEL

Remarks:

fetotoxicity

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Remarks:

The fetal parameters were not affected up to and including the highest dose level of 1000 mg/kg body weight/day.

Dose descriptor:

NOAEL

Remarks:

teratogenicity

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Remarks:

The fetal parameters were not affected up to and including the highest dose level of 1000 mg/kg body weight/day.

Abnormalities:

no effects observed

Developmental effects observed:

no

Conclusions:

The test substance did not reveal any teratogenic potential up to and including the highest dose level of 1000 mg/kg body weight/day.
The no-observed adverse effect level for the maternal organism was considered to be 300 mg/kg and for the fetal organism 1000 mg/kg body weight/day.

Executive summary:

The purpose of this study was to assess the effects of the test substance on embryonic and fetal development in pregnant Chinchilla rabbits.

Each group consisted of 16 mated female rabbits. The test substance was administered orally by gavage once daily from day 6 through to day 18 post coitum, at dose levels of:

Group 1:       0 mg/kg body weight/day (vehicle control)

Group 2:       100 mg/kg body weight/day

Group 3:       300 mg/kg body weight/day

Group 4:       1000 mg/kg body weight/day

The dosages were based on the results of a dose range-finding study. A standard dose volume of 4 ml/kg body weight with a daily adjustment to the actual body weight was used. Control animals were dosed with the vehicle alone (bi-distilled water with 0.5 % Cremophor).

Females were sacrificed on day 28 post coitum and the fetuses were removed by Caesarean section. The examination of the dams and fetuses was performed in accordance with international recommendations.

The following results were obtained:

MATERNAL DATA

GENERAL TOLERABILITY

- There were no deaths, clinical signs or necropsy findings in the females of any dose group which were considered to be related to administration of the test substance.

- Test article-related reduced food consumption (statistically significant between days 11-15 post coitum) was evident during the dosing period at 1000 mg/kg. During this period, the body weight gain was slightly reduced (without statistical significance).

No effects on food consumption and body weight development were noted at 100 mg/kg or at 300 mg/kg.

REPRODUCTION PARAMETERS

- None of the differences between the vehicle control group and any dose group noted were considered to be an effect of administration of the test substance. The differences evident were considered to be incidental because of missing dose-relation.

FETAL DATA

- During external and fresh visceral examination as well as at examination of fetal heads by Wilson technique and skeletal examination of fetuses, no abnormal findings were evident which indicated test article-related effects.

The isolated common abnormal findings (with the lowest incidence at 1000 mg/kg) were within the normal range of spontaneously occurring findings in this rabbit strain and were considered to be incidental.

- The other fetal parameters recorded - sex ratios, body weights and stage of skeletal development - resulted in similar values in all groups.

Reference 2

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

August - September 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Version / remarks:

May 12, 1981

Deviations:

no

GLP compliance:

yes

Limit test:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Lot/batch No.of test material: 903069
- Expiration date of the lot/batch: November 17, 1990

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature, in the dark
- Stability of the test substance in the solvent/vehicle: at least 2 hours

Species:

rat

Strain:

Wistar

Remarks:

SPF

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: BRL, Biological Research Laboratories Ltd. / Wolferstrasse 4 / CH 4414 Fullinsdorf / Switzerland
- Age at study initiation (pairing): 11 week minimum
- Weight at study initiation (day 0 post coitum): 179-226 g
- Housing: single
- Diet (e.g. ad libitum): ad libitum; Pelleted standard Kliba 343 rat/mouse maintenance diet ("Kliba", Klingentalmuehle AG, CH 4303 Kaiseraugst/Switzerland)
- Water (e.g. ad libitum): Tap water was available ad libitum
- Acclimation period: 10 days under test conditions, after veterinary examination

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3°C
- Humidity (%): 40-70%
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light):12 hours artificial fluorescent light/12 hours dark with background music (Schweizerischer Telefonrundspruch) played at a centrally defined low volume for at least 8 hours during the light period

IN-LIFE DATES: From: July, 27 To: August 31, 1990

Route of administration:

oral: gavage

Vehicle:

other: Bi-distilled water with 0.5% Cremophor (BASF)

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
The mixtures of the test article and vehicle were prepared daily before administration. The test substance was weighed into a glass beaker on a tared precision balance (Mettler PE 360) and the vehicle added (w/w). The mixtures were prepared using a homogenizer. During the daily administration period, homogeneity was maintained using a magnetic stirrer.

The test article was administered orally, by gavage, once daily in the morning from day 6 through to day 15 post coitum. All groups received a dose volume of 10 ml/kg body weight, with a daily adjustment of the individual volume to the actual body weight. Control animals were similarly dosed with the vehicle alone
VEHICLE
- Justification for use and choice of vehicle (if other than water): common vehicle
- Concentration in vehicle: 5 mg/ml, 15 mg/ml, 45 mg/ml

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Photometric analytical verification (UV/Vis)
Concentrations (5, 15, 150 mg/ml) and stability in bidestilled water with 0.5% Cremophor was verified.
Result: Recovery between 99.4 and 103.8%
Homogeneity varies from -4 to + 5%

Details on mating procedure:

- Impregnation procedure: cohoused
- If cohoused:
- M/F ratio per cage: 1/1
- Length of cohabitation: overnight
- Further matings after two unsuccessful attempts: no information
- Proof of pregnancy: vaginal plug / sperm in vaginal smear referred to as day 0 post coitum

Duration of treatment / exposure:

from day 6 through to day 15 post coitum

Frequency of treatment:

once daily in the morning

Duration of test:

21 days (from successful mating to termination, excluding acclimatisation etc)

Dose / conc.:

50 mg/kg bw/day (nominal)

Dose / conc.:

150 mg/kg bw/day (nominal)

Dose / conc.:

450 mg/kg bw/day (nominal)

No. of animals per sex per dose:

25 mated female rats

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Dosages were based on the results of a dose range-finding study.

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily
- Cage side observations checked: Signs of mortalities, reaction to treatment and of ill health were observed.

DETAILED CLINICAL OBSERVATIONS: No

BODY WEIGHT: Yes
- Time schedule for examinations: daily from day 0 until 21 post coitum

FOOD CONSUMPTION AND COMPOUND INTAKE: Yes
- Time schedule: days 0-6, 6-11, 11-16 and 16-21 post coitum
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes

WATER CONSUMPTION AND COMPOUND INTAKE: No

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on day 21 post coitum
- Organs examined: post mortem examination, including gross macroscopic examination of all internal organs, with emphasis on the uterus, uterine contents, position of fetuses in the uterus and number of corpora lutea
- Uteri (and contents) of all females with live fetuses were weighed at necropsy

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 (embryonic resoption): Yes
- Number of late resorptions (fetal resorption): Yes
- Number of Pre-Implantation loss: yes
- Number of Post-Implantation loss: yes

Fetal examinations:

- External examinations: Yes; all per litter
- Soft tissue examinations: Yes: half per litter
- Skeletal examinations: Yes; half per litter
- Head examinations: not specified

Statistics:

- Univariate one-way analysis of variance was used to assess the significance of intergroup differences.
- If the variables could be assumed to follow a normal distribution, the Dunnett-test (many-one t-test), based on a pooled variance estimate, was applied for the comparison between the treated groups and the control group.
- The Steel-test (many-one rank test) was applied when the data could not be assumed to follow a normal distribution.
- Fisher's Exact test for 2x2 tables was applied if the variables could be dichotomized without loss of information.

Indices:

see "Any other information on materials and methods incl. tables"

Historical control data:

- historical reproductive data of Wistar rats (SPF quality); 1987/ 1988/ 1989/ 1990
- spontaneous abnormal findings of Wistar rats (SPF quality); 1987/ 1988/ 1989/ 1990

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

- The dams at 450 mg/kg body weight/day group showed severe clinical signs of reaction to treatment (in the main ruffled fur, ventral recumbency, dyspnoea and apath), in particular from days 8 to 14 post coitum (3th to 9th day of dosing period, respectively).
- In 4 animals, respectively, on day 10 and/or 11 post coitum and in 1 animal on day 12 post coitum, comatose state was noted during a few hours.

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

- group 4 (450 mg/kg) dams: stagnation of the body weight gain between days 6 and 9 post coitum; during the rest of the treatment period slightly retarded body weight gain; slightly reduced corrected body weight gain (corrected for uterus weight) (4.9% vs. 7.8 % in the vehicle control)

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

- group 4 (450 mg/kg) dams: reduction in food consumption (-24.1 and -18% between days 6-11 or 11-16 post coitum compared to vehicle control)
- group 3 (150 mg/kg) dams: reduction in food consumption (-6.1% compared to vehicle control)

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:

effects observed, non-treatment-related

Description (incidence and severity):

- one female of group 1 (vehicle control) and 2 females of group 3 (150 mg/kg): blood in the uterus
- one female of group 4 (450 mg/kg): hairloss on the abdomen

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

no effects observed

Number of abortions:

no effects observed

Pre- and post-implantation loss:

effects observed, treatment-related

Description (incidence and severity):

- group 4 (450 mg/kg bw/d) dams: marginally increased post-implantation loss (9.4% vs. 5.6% in the vehicle control)

Total litter losses by resorption:

no effects observed

Early or late resorptions:

no effects observed

Dead fetuses:

no effects observed

Changes in pregnancy duration:

not examined

Description (incidence and severity):

Migrated Data from removed field(s)
Field "Effects on pregnancy duration" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsMaternalAnimals.MaternalDevelopmentalToxicity.EffectsOnPregnancyDuration): not examined

Changes in number of pregnant:

no effects observed

Other effects:

no effects observed

Dose descriptor:

NOAEL

Effect level:

50 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

food consumption and compound intake

Abnormalities:

no effects observed

Fetal body weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

- 1 in group 3 (150 mg/kg) and 1 in group 4 (450 mg/kg): runts

Isolated occurrence of runts are not unusual in rats of this strain. Therefore, these findings were considered to be incidental and not related to treatment with the test article.
Migrated Data from removed field(s)
Field "Fetal/pup body weight changes" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.FetalPupBodyWeightChanges): effects observed, treatment-related
Field "Description (incidence and severity)" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.DescriptionIncidenceAndSeverityFetalPupBodyWeightChanges): - group 4 (450 mg/kg): the mean fetal body weight was significantly reduced by 8.5% in comparison with the vehicle control

Reduction in number of live offspring:

no effects observed

Description (incidence and severity):

no dead fetuses

Changes in sex ratio:

no effects observed

Changes in litter size and weights:

not examined

Changes in postnatal survival:

not examined

External malformations:

effects observed, non-treatment-related

Description (incidence and severity):

- 1 fetus of group 2 (50 mg/kg) and 1 fetus of group 3 (150 mg/kg): caudal malposition of the right or of both hind legs

Isolated occurrence of caudally malpositioned hindlegs are not unusual in rats of this strain. Therefore, these findings were considered to be incidental and not related to treatment with the test article.

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

5/150 control fetuses (in 4 litters),
4/150 fetuses at 50 mg/kg (in 4 litters),
3/137 fetuses at 150 mg/kg (in 3 litters) and
12/147 fetuses at 450 mg/kg (in 9 litters)

- mainly wavy ribs and dumbbell shaped thoracic vertebral bodies (common findings in rats of this strain)
- statistical significant differernces in group 4 (450 mg/kg) from vehicle control: retardation in skeletal development (non-ossified cervical vertebrae or phalangeal nuclei or incompletely ossified sternebrae)
- slightly increased incidence of abnormal findings in group 4 (450 mg/kg) in comparison with the concurrent vehicle control group was related to the reduced mean fetal body weight and was not considered to be a specific teratogenic effect of the test article

Visceral malformations:

effects observed, non-treatment-related

Description (incidence and severity):

- 1/137 fetuses of the vehicle control and 1/134 fetuses of group 4 (450 mg/kg): pelvic dilation of the right kidney

These findings were considered to be incidental.

Other effects:

no effects observed

Dose descriptor:

NOAEL

Remarks:

fetotoxicity

Effect level:

150 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

fetal/pup body weight changes

Dose descriptor:

NOAEL

Remarks:

teratogenicity

Effect level:

450 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Abnormalities:

effects observed, non-treatment-related

Description (incidence and severity):

External and visceral examination of the fetuses, did not reveal any treatment related effects up to and including the dose level of 450 mg/kg body weight/day.
The retardation in skeletal development noted for the fetuses at 450 mg/kg correlated with the reduced mean fetal body weight noted in this group. The abnormal skeletal findings in the 450 mg/kg group were not considered to be a specific teratogenic effect of the test article.

Developmental effects observed:

yes

Lowest effective dose / conc.:

450 mg/kg bw/day (nominal)

Treatment related:

yes

Relation to maternal toxicity:

developmental effects as a secondary non-specific consequence of maternal toxicity effects

Dose response relationship:

yes

Table 1: Differences in food comsumption of dams, mean (g/animal/day)

Group         Days post coitum

0 - 6                     6 - 11                       11 - 16              6 - 16**            16 - 21

(mg/kg)    g (%)*                   g (%)*                       g (%)*               

1                 17.5                       19.5                            23.3                     21.4                      22.5

(0)

2                 17.7                      18.8                             23.1                     21.0                      22.6

(50)          (+1.1)                 (-3.6)                        (-0.9)               (-1.9)                  (+0.4)

3                 17.8                      18.2                             21.9                     20.1                     22.4

(150)          (+1.7)                    (-6.7)                       (-6.0)              (-6.1)                  (-0.4)

4                  18.1                      14.8                            19.1                     17.0                     21.8

(450)         (+3.4)                 (-24.1)                    (-18.0)            (-20.6)                 (-3.1)

* = Percentages refer to the values of group 1.

** = The calculations of food consumption and body weight gain during the treatment period started on day 6 post coitum (immediately prior to the first administration)and ended on day 16 post coitum(approximately 24 hours after the last administration).

Conclusions:

Based on these results, the no-observed adverse effect level for the maternal organism was considered to be 50 mg/kg body weight/day and for the fetal organism 150 mg/kg body weight/day.
Under the conditions described in this study, the test substance did not reveal any teratogenic potential up to and including the highest dose level of 450 mg/kg body weight/day.

Executive summary:

The purpose of this study was to assess the effects of the test substance on embryonic and fetal development in pregnant Wistar rats. Each group consisted of 25 mated female rats. The test substance was administered orally by gavage once daily from day 6 through to day 15 post coitum, at dose levels of:

Group 1: 0 mg/kg body weight/day (vehicle control)

Group 2: 50 mg/kg body weight/day

Group 3: 150 mg/kg body weight/day

Group 4: 450 mg/kg body weight/day

The dosages were based on the results of a dose range-finding study. A standard dose volume of 10 ml/kg body weight with a daily adjustment to the actual body weight was used. Control animals were dosed with the vehicle alone (bi-distilled water with 0.5% Cremophor). Females were sacrificed on day 21 post coitum and the fetuses were removed by Caesarean section. The examination of the dams and fetuses was performed in accordance with international recommendations.

The following results were obtained:

MATERNAL DATA

GENERAL TOLERABILITY

- Administration of the test substance caused severe clinical signs of reaction to treatment at 450 mg/kg during the dosing period. Ruffled fur, ventral recumbency, dyspnoea, apathy and in 4 dams comatose state were observed. No clinical signs of reaction to treatment were noted at 50 or 150 mg/kg.

- Dose related reduced food consumption was noted at 150 and 450 mg/kg during the dosing period. This finding was considered to be test article related. No effects of test article on the food consumption of the dams were noted at 50 mg/kg.

- Stagnation of the body weight gain from the first to the fourth day of the dosing period and retardation of the body weight gain during the rest of the treatment period were noted for the dams at 450 mg/kg. No test article related effects on the body weight of the dams were evident at 50 or 150 mg/kg.

- At terminal necropsy of the dams, no test article related abnormal findings were noted.

REPRODUCTION PARAMETERS

- At 450 mg/kg, the marginally increased post-implantation loss was considered to be an effect of treatment with the test article. The maternal reproduction parameters of the dams at 50 or 150 mg/kg were not affected by treatment with the test substance.

FETAL DATA

- Sex ratios of the fetuses were not affected by treatment with the test article.

- At 450 mg/kg, test article related reduction in mean fetal body weight was noted.

No effects on the mean body weight of the fetuses were evident at 50 or 150 mg/kg.

- None of the few abnormal findings noted at external or visceral examination by Wilson technique of the fetuses indicated a test article related effect.

- At skeletal examination of the fetuses, the slightly increased incidence of fetuses with abnormal findings and the retardation in skeletal development noted for the fetuses at 450 mg/kg correlated with the reduced mean fetal body weight noted in this group. The abnormal skeletal findings in the 450 mg/kg group were not considered to be a specific teratogenic effect of the test article.

Reference 3

Endpoint:

developmental toxicity

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

see attached RA justification

Reason / purpose for cross-reference:

read-across source

Dose descriptor:

NOAEL

Effect level:

300 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

body weight and weight gain

food consumption and compound intake

Abnormalities:

no effects observed

Dose descriptor:

NOAEL

Remarks:

fetotoxicity

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Remarks:

The fetal parameters were not affected up to and including the highest dose level of 1000 mg/kg body weight/day.

Dose descriptor:

NOAEL

Remarks:

teratogenicity

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Remarks:

The fetal parameters were not affected up to and including the highest dose level of 1000 mg/kg body weight/day.

Developmental effects observed:

no

Conclusions:

The test substance did not reveal any teratogenic potential up to and including the highest dose level of 1000 mg/kg body weight/day.
The no-observed adverse effect level for the maternal organism was considered to be 300 mg/kg and for the fetal organism 1000 mg/kg body weight/day.

Executive summary:

The purpose of this study was to assess the effects of the "analog test substance" on embryonic and fetal development in pregnant Chinchilla rabbits.

Each group consisted of 16 mated female rabbits. The test substance was administered orally by gavage once daily from day 6 through to day 18 post coitum, at dose levels of:

Group 1:       0 mg/kg body weight/day (vehicle control)

Group 2:       100 mg/kg body weight/day

Group 3:       300 mg/kg body weight/day

Group 4:       1000 mg/kg body weight/day

The dosages were based on the results of a dose range-finding study. A standard dose volume of 4 ml/kg body weight with a daily adjustment to the actual body weight was used. Control animals were dosed with the vehicle alone (bi-distilled water with 0.5 % Cremophor).

Females were sacrificed on day 28 post coitum and the fetuses were removed by Caesarean section. The examination of the dams and fetuses was performed in accordance with international recommendations.

The following results were obtained:

MATERNAL DATA

GENERAL TOLERABILITY

- There were no deaths, clinical signs or necropsy findings in the females of any dose group which were considered to be related to administration of the test substance.

- Test article-related reduced food consumption (statistically significant between days 11-15 post coitum) was evident during the dosing period at 1000 mg/kg. During this period, the body weight gain was slightly reduced (without statistical significance).

No effects on food consumption and body weight development were noted at 100 mg/kg or at 300 mg/kg.

REPRODUCTION PARAMETERS

- None of the differences between the vehicle control group and any dose group noted were considered to be an effect of administration of the test substance. The differences evident were considered to be incidental because of missing dose-relation.

FETAL DATA

- During external and fresh visceral examination as well as at examination of fetal heads by Wilson technique and skeletal examination of fetuses, no abnormal findings were evident which indicated test article-related effects.

The isolated common abnormal findings (with the lowest incidence at 1000 mg/kg) were within the normal range of spontaneously occurring findings in this rabbit strain and were considered to be incidental.

- The other fetal parameters recorded - sex ratios, body weights and stage of skeletal development - resulted in similar values in all groups.

Reference 4

Endpoint:

developmental toxicity

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

see attached RA justification

Reason / purpose for cross-reference:

read-across source

Dose descriptor:

NOAEL

Effect level:

50 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

food consumption and compound intake

Abnormalities:

no effects observed

Dose descriptor:

NOAEL

Remarks:

fetotoxicity

Effect level:

150 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

fetal/pup body weight changes

Dose descriptor:

NOAEL

Remarks:

teratogenicity

Effect level:

450 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Abnormalities:

effects observed, non-treatment-related

Description (incidence and severity):

External and visceral examination of the fetuses did not reveal any treatment related effects up to and including the dose level of 450 mg/kg body weight/day.
The retardation in skeletal development noted for the fetuses at 450 mg/kg correlated with the reduced mean fetal body weight noted in this group. The abnormal skeletal findings in the 450 mg/kg group were not considered to be a specific teratogenic effect of the test article.

Developmental effects observed:

yes

Lowest effective dose / conc.:

450 mg/kg bw/day (nominal)

Treatment related:

yes

Relation to maternal toxicity:

developmental effects as a secondary non-specific consequence of maternal toxicity effects

Dose response relationship:

yes

Conclusions:

Based on these results, the no-observed adverse effect level for the maternal organism was considered to be 50 mg/kg body weight/day and for the fetal organism 150 mg/kg body weight/day.
Under the conditions described in this study, the test substance did not reveal any teratogenic potential up to and including the highest dose level of 450 mg/kg body weight/day.

Executive summary:

The purpose of this study was to assess the effects of the "analog test substance" on embryonic and fetal development in pregnant Wistar rats. Each group consisted of 25 mated female rats. The test substance was administered orally by gavage once daily from day 6 through to day 15 post coitum, at dose levels of:

Group 1: 0 mg/kg body weight/day (vehicle control)

Group 2: 50 mg/kg body weight/day

Group 3: 150 mg/kg body weight/day

Group 4: 450 mg/kg body weight/day

The dosages were based on the results of a dose range-finding study. A standard dose volume of 10 ml/kg body weight with a daily adjustment to the actual body weight was used. Control animals were dosed with the vehicle alone (bi-distilled water with 0.5% Cremophor). Females were sacrificed on day 21 post coitum and the fetuses were removed by Caesarean section. The examination of the dams and fetuses was performed in accordance with international recommendations.

The following results were obtained:

MATERNAL DATA

GENERAL TOLERABILITY

- Administration of the test substance caused severe clinical signs of reaction to treatment at 450 mg/kg during the dosing period. Ruffled fur, ventral recumbency, dyspnoea, apathy and in 4 dams comatose state were observed. No clinical signs of reaction to treatment were noted at 50 or 150 mg/kg.

- Dose related reduced food consumption was noted at 150 and 450 mg/kg during the dosing period. This finding was considered to be test article related. No effects of test article on the food consumption of the dams were noted at 50 mg/kg.

- Stagnation of the body weight gain from the first to the fourth day of the dosing period and retardation of the body weight gain during the rest of the treatment period were noted for the dams at 450 mg/kg. No test article related effects on the body weight of the dams were evident at 50 or 150 mg/kg.

- At terminal necropsy of the dams, no test article related abnormal findings were noted.

REPRODUCTION PARAMETERS

- At 450 mg/kg, the marginally increased post-implantation loss was considered to be an effect of treatment with the test article. The maternal reproduction parameters of the dams at 50 or 150 mg/kg were not affected by treatment with the test substance.

FETAL DATA

- Sex ratios of the fetuses were not affected by treatment with the test article.

- At 450 mg/kg, test article related reduction in mean fetal body weight was noted.

No effects on the mean body weight of the fetuses were evident at 50 or 150 mg/kg.

- None of the few abnormal findings noted at external or visceral examination by Wilson technique of the fetuses indicated a test article related effect.

- At skeletal examination of the fetuses, the slightly increased incidence of fetuses with abnormal findings and the retardation in skeletal development noted for the fetuses at 450 mg/kg correlated with the reduced mean fetal body weight noted in this group. The abnormal skeletal findings in the 450 mg/kg group were not considered to be a specific teratogenic effect of the test article.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Additional information

There are no valid teratogenicity in vivo studies for pure N,N-dimethyldecanamide. Nevertheless teratogenicity was investigated with a mixture of N,N-dimethyldecanamide and N,N-dimethyloctanamide (with traces of N,N-dimethyl-dodecanamide and N,N-dimethyl-hexanamide). Due to the fact that a high amount in the mixture was N,N-dimethyl-decanamide and the rest of the mixture are homologues with a lower and higher molecular weight which can be assumed to have a similar toxicological behaviour it is concluded that the mixture has an nearly similar toxicological behaviour like pure N,N-dimethyldecanamide, further details can be found in the attached RA justification in chapter 13.

Valid data are available to assess the teratogenicity in rats and rabbits.

Teratogenicity study with a mixture of N,N-dimethyldecanamide and N,N-dimethyloctanamide in rats:

In a study according to OECD 414 (RCC 1991) the mixture was administered orally by gavage, once daily, to mated female Wistar rats at dosages of 50, 150 or 450 mg/kg body weight/day from day 6 through to day 15 post coitum in order to assess the effects on embryonic and fetal development. In the dams at 450 mg/kg body weight/day, severe clinical signs of reaction to treatment, reduced food consumption and reduced body weight gain were observed. Additionally, at this dose level slightly increased post-implantation loss, reduced mean fetal body weights, an increased incidence of fetuses with common abnormal skeletal findings and retardations in skeletal development were noted. At 150 mg/kg body weight/day, there was a slight reduction in food consumption during the dosing period. At this dose level no effects on the maternal reproduction parameters or on the fetal parameters were noted. External and visceral examination of the fetuses, did not reveal any treatment related effects up to and including the dose level of 450 mg/kg body weight/day. Based on these results the author concluded that, the no-observed adverse effect level (NOAEL) for the maternal organism was considered to be 50 mg/kg body weight/day and for the fetal organism 150 mg/kg body weight/day and that under the conditions described in this study,the test substancedid not reveal any teratogenic potential up to and including the highest dose level of 450 mg/kg body weight/day.

Overall the study shows toxic effect to maternal and fetal organism, whereas the maternal organism reacts earlier and the fetus is only affected in higher dosages but the study did not show any teratogenic effect up to and including the highest dosage tested. The NOAELs derived were only based on weight reduction/slight reduced food comsumption by the author and considered by the applicant to be less relevant in the view of all available information.

Teratogenicity study with a mixture of N,N-dimethyldecanamide and N,N-dimethyloctanamide in rabbits:

A teratogenicity study according to OECD 414 was conducted to assess the effects of the test substance on embryonic and fetal development in pregnant Chinchilla rabbits (Bayer 1991). Therefore groups of 16 mated female rabbit received the test substance orally by gavage once daily from day 6 through to day 18 post coitum, at dose levels of:   0 mg/kg body weight/day (vehicle control), 100 mg/kg body weight/day, 300 mg/kg body and 1000 mg/kg body weight/day. The dosages were based on the results of a dose range-finding study. A standard dose volume of 4 ml/kg body weight with a daily adjustment to the actual body weight was used. Control animals were dosed with the vehicle alone (bi-distilled water with 0.5 % Cremophor).

Females were sacrificed on day 28 post coitum and the fetuses were removed by Caesarean section. The examination of the dams and fetuses was performed in accordance with international recommendations.

The following results were obtained:

Concerning maternal general tolerabiltiy there were no deaths, clinical signs or necropsy findings in the females of any dose group which were considered to be related to administration of the test substance. Further test article-related reduced food consumption (statistically significant between days 11-15 post coitum) was evident during the dosing period at 1000 mg/kg. During this period, the body weight gain was slightly reduced (without statistical significance) but no effects on food consumption and body weight development were noted at 100 mg/kg or at 300 mg/kg.

Concerning reproductions parameters none of the differences between the vehicle control group and any dose group noted were considered to be an effect of administration of the test substance. The differences evident were considered to be incidental because of missing dose-relation.

Concerning fetal data, during external and fresh visceral examination as well as at examination of fetal heads by Wilson technique and skeletal examination of fetuses, no abnormal findings were evident which indicated test article-related effects. The isolated common abnormal findings (with the lowest incidence at 1000 mg/kg) were within the normal range of spontaneously occurring findings in this rabbit strain and were considered to be incidental. Further the other fetal parameters recorded - sex ratios, body weights and stage of skeletal development - resulted in similar values in all groups.

Taken together no signs of teratogenicity are observed within OECD 414 studies conducted in rats and rabbits. Concluding there is no concerning teratogenicity for N,N-Dimethyldecanamid.

Key study assignment:

As there is only one reliable and relevant study per species available, this study is used as key study.

Justification for classification or non-classification

Due to citeria of legislation GHS (Regulation (EU) 1272/2008) for reproductive toxicans ("Suspected human reproductive toxicant Substances are classified in Category 2 for reproductive toxicity when there is some evidence from humans or experimental animals, possibly supplemented with other information......") the substance is not be classified as reproductive toxican as there is no evidence from the current available data. Also according to DSD (67/548/EEC) the available test results led not to a classification as reproductiv toxican.

Labelling for toxicity to reproduction:

GHS: no classification

DSD: no classification