Reaction mass of 1-phenyloctadecane-1,3-dione and phenylicosane-1,3-dione

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 20 June 2013 to 31 October 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant study conducted according to OECD guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of 1-phenyloctadecane-1,3-dione and phenylicosane-1,3-dione

EC Number:

915-316-2

Molecular formula:

C50H80O4

IUPAC Name:

Reaction mass of 1-phenyloctadecane-1,3-dione and phenylicosane-1,3-dione

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Test animals

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Janvier, le Genest-Saint-Isle, France.
- Age at study initiation: 10/11 weeks old
- Weight at study initiation: mean body weight of 241 g
- Fasting period before study: no
- Housing: The animals were individually housed in polycarbonate cages (Tecniplast 2154, 940 cm2) with stainless steel lids and containing autoclaved sawdust (SICSA, Alfortville, France). Each cage contained enrichment (rat hut).
- Diet: SSNIFF R/M-H pelleted maintenance diet ad libitum
- Water: tap water ad libitum
- Acclimation period: 4 or 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2°C
- Humidity (%): 50 ± 20%
- Air changes (per hr): approximately 12 cycles/hour of filtered, non-recycled air.
- Photoperiod (hrs dark / hrs light): 12h/12h

IN-LIFE DATES: From: 20 Jun 2012 To: 17 Sep 2013

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 0.5% aqueous methylcellulose

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
The test item was administered as a suspension in the vehicle. The test item dose formulations were prepared daily and delivered to the study room at room temperature. Before the start of treatment, the suitability of the proposed preparation process was confirmed by analysis of the homogeneity, as described in CiToxLAB France/Study No. 39795 AHS (data not shown).

ADMINISTRATION OF DOSING SOLUTIONS:
The dose formulations were administered by gavage, using a plastic syringe fitted with a metal gavage tube, once a day, at approximately the same time. The quantity of the dose formulation administered to each animal was adjusted according to the most recently recorded body weight. A constant dosage-volume of 5 mL/kg/day was used.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The concentration of the test item in samples of each control and test item dose formulation prepared for use on the first and last days of treatment of the study was determined using Gas Chromatography with FID detection (GC-FID) analytical method.

Details on mating procedure:

The females were mated at the breeder's facilities. The day of confirmed mating (detection of a vaginal plug) was designated as day 0 post-coitum (p.c.).

Duration of treatment / exposure:

From day 6 to day 20 p.c., inclusive.

Frequency of treatment:

daily

Duration of test:

see above

Doses / concentrations

Remarks:

Doses / Concentrations:
100, 300, 1000 mg/kg bw/day
Basis:
other: actual ingested without correction for active substance content

No. of animals per sex per dose:

24 females/dose

Control animals:

yes, concurrent vehicle

Details on study design:

The dose-levels were selected based on a previous preliminary study of prenatal developmental toxicity by gavage in Sprague-Dawley rats (CiToxLAB France/Study No. 40255 RSR). In this study, 4 groups of 5 females were given the test item at 0, 100, 300 or 1000 mg/kg/day in 0.5% aqueous methylcellulose from Days 6 to 20 p.c. at a constant dose-volume of 5 mL/kg/day. There were no test item-related mortality or clinical signs. A tendency towards a lower mean body weight gain over the treatment period and a lower mean gravid uterus weight were observed at 1000 mg/kg/day when compared with controls. At hysterectomy, there was also at 1000 mg/kg/day a trend towards a higher mean post-implantation loss du to a higher mean number of early resorption which led towards a slightly lower mean number of fetuses at this dose-level, when compared with controls. Based on the absence of adverse effects up to the highest dose of 1000 mg/kg/day, the same dose-levels were chosen for the main study.

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Each animal was checked for mortality and morbidity once a day before the treatment period and at least twice a day during the treatment period, including weekends and public holidays.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: From arrival, each animal was observed once a day as part of the routine examinations. From the start of the treatment period, each animal was observed once a day, at approximately the same time, for the recording of clinical signs.

BODY WEIGHT: Yes
- Time schedule for examinations: on days 2, 4, 6, 9, 12, 15, 18 and 21 p.c..

FOOD CONSUMPTION: Yes
- The quantity of food consumed by each female was recorded for the following intervals: days 2-4, 4-6, 6-9, 9-12, 12-15, 15-18 and 18-21 p.c..

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

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 21
- Organs examined: Females were submitted for a macroscopic post-mortem examination of the principal thoracic and abdominal organs.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: Yes
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes
- Other:
- number and distribution of uterine scars
- number and distribution of dead and live fetuses.
- A gross evaluation of placentas was also undertaken.

Fetal examinations:

- External examinations (included the observation of all visible structures, surfaces and orifices): Yes: [all per litter]
- Soft tissue examinations (included the observation of all the organs and structures of the neck, thorax and abdomen): Yes: [half per litter]
- Skeletal examinations (included the observation of all the bones and cartilage structures of the head, spine, rib cage, pelvis and limbs): Yes: [half per litter]
- Head examinations: Yes: [ half per litter]

Others:
- The body weight of each live fetus was recorded.
- The sex of each fetus was determined at the time of hysterectomy.The sex of fetuses was determined by visual assessment of anogenital distance and was confirmed by examination of sexual organs at detailed dissection of the soft tissues or at evisceration.

Statistics:

Mean values were compared by one-way analysis of variance and Dunnett test (mean values being considered as normally distributed and variances being considered as homogeneous). Percentage values were compared by Fisher exact probability test.

Indices:

The following parameters will be calculated:

For each pregnant female:
 body weight change for different intervals,

 net body weight (presented as carcass weight):
Body weight on day 21 p.c. - gravid uterine weight

 net body weight change:
Body weight on day 21 p.c. - body weight on day 6 p.c. - gravid uterine weight

For each litter:
 total number of resorptions:
Sum of scars + early resorptions + late resorptions

 total number of dead fetuses:
Sum of dead males + dead females + undefined dead fetuses

 % of dead fetuses per litter:
Total number of dead fetuses
__________________________x 100
Number of implantation sites

 total number of live fetuses:
Sum of live male + live female fetuses

 % of live fetuses per litter:
Total number of live fetuses
__________________________x 100
Number of implantation sites

 % of pre-implantation loss:
Number of corpora lutea - Number of implantations
_______________________________________________x 100
Number of corpora lutea

 % of post-implantation loss:
Number of implantation sites - Number of live fetuses
________________________________________________x 100
Number of implantation sites

 average fetal body weight:
Sum of individual fetal weights
___________________________
Number of fetuses

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Effect levels (maternal animals)

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Effect levels (fetuses)

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Basis for effect level:

other: teratogenicity

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Any other information on results incl. tables

The test item concentrations in the administered dose formulations analyzed in weeks 1 and 3 remained within an acceptable range of variation (+1.7% to +2.5%) when compared to the nominal values.

Pregnancy status:

At termination on day 21 p.c., there were 21, 21, 23 and 22 dams with live fetuses in the vehicle control, 100, 300 and 1000 mg/kg/day groups, respectively.

Mortality:

There were no unscheduled deaths.

Clinical signs:

At 1000 mg/kg/day, ptyalism was recorded in 4/24 females and reflux at dosing in 1/24 females. These findings were considered to be of minor toxicological significance.

Body weight, body weight change and food consumption:

There were no toxicologically relevant effects on mean body weight and mean body weight gain.

The only effect of the test item treatment on mean food consumption was a decrease at 1000 mg/kg/day at the very beginning of the treatment period. This variation was considered not to be adverse owing to its small amplitude compared with controls and to its transient occurrence.

Necropsy and hysterectomy data:

There were no test item-related macroscopic changes. The only finding wasdilated renal pelvis in one female at 100 mg/kg/day.

There were no toxicologically relevant effects on mean hysterectomy data (pre- and post-implantation losses and early and late resorptions).

Fetal examination:

There were no effects of the treatment with the test item on mean fetal body weights or fetal sex ratios.

- External examination:

There were no external variations. External malformations consisted in omphalocele, anasarca and maxillary micrognathia seen in one fetus at 1000 mg/kg and agnathia seen in one fetus at 300 mg/kg. Although the external malformations were seen at 300 and mainly 1000 mg/kg/day, an effect of the test item treatment was considered unlikely. Indeed, these few malformations were recorded with isolated incidence and generally with several other defects (see paragraph related skeletal examination). They can also be sporadically observed in this species.

- Soft tissues examination:

There were no visceral malformations and no test item-related visceral variations.Variations recorded (dilated renal pelvis, dilated ureter and colored adrenal gland) were of common background in Sprague-Dawley fetuses and/or of isolated incidence.

- Skeletal examination:

Skeletal malformations were reported in the two fetuses with the external malformations (see paragraph related to external examination). These were the fetuses with the lowest body weight (less than 4g): At 1000 mg/kg/day, the anasarca fetus with maxillary micrognathia had also defects or incomplete/no ossification in thoracic and lumbar vertebra(e). At 300 mg/kg/day, the fetus with agnatia had fused and misshapen mandible. These abnormal fetuses were considered to be fortuitous.

Skeletal variations (enlarged fontanel, unossified distal phalanx (forepaw), incomplete ossification (mainly) or unossified of the hyoid) were considered to be of no toxicological significance, as their fetal and litter incidences were not significantly increased compared to controls and/or as they were noted with no dose-relationship.

Applicant's summary and conclusion

Conclusions:

The test item, Rhodiastab 55P, was administered by gavage, once daily, from days 6 to 20 post-coitum, inclusive, to mated female Sprague-Dawley rats at dosages of 100, 300 or 1000 mg/kg/day in a GLP-compliant study in accordance with OECD Guideline 414.
On the basis of the results obtained in this study:
- the No Observed Adverse Effect Level (NOAEL) for maternal parameters was considered to be 1000 mg/kg/day,
- the NOAEL for embryo-fetal development was considered to be 1000 mg/kg/day.
The test item, Rhodiastab 55P, did not elicit any teratogenic potential.

Based on the results of this study, the test substance Rhodiastab 55P is not classified for developmental toxicity / teratogenicity according to the classification criteria of the Regulation (EC) 1272/2008 (CLP) and of the Directive 67/548/EEC.

Executive summary:

The potential toxic effects of the test item, Rhodiastab 55P, on the pregnant female and on embryonic and fetal development following daily oral administration (gavage) to pregnant female rats from implantation to the day prior to the scheduled hysterectomy (day 6 to day 20 post-coitum inclusive) was investigated in a GLP-compliant study in accordance with OECD Guideline 414.

In this study, three groups of 24 time-mated Sprague-DawleyRjHan rats were administered the test item, RHODIASTAB 55P (batch No. 1124401), once daily from Day 6 to Day 20p.c., by gavage at doses of 100, 300 or 1000 mg/kg/day. An additional group of 24 time-mated females received the vehicle, 0.5% aqueous methylcellulose, under the same experimental conditions and acted as the control group.A dose-volume of 5 mL/kg/day was used. The animals were checked daily for mortality and clinical signs. Body weight and food consumption were recorded every 2 or 3 days. On Day 21p.c., females were sacrificed and submitted to a macroscopicpost‑mortemexamination. Hysterectomy was performed and the numbers ofcorpora lutea, implantation sites, early and late resorptions, and live and dead fetuses were recorded. The fetuses were weighed, sexed and examined for external, soft tissue and/or skeletal (bones + cartilage) abnormalities.

 

The test item concentrations in the administered dose formulations analyzed were within the acceptance criteria (±15% of the nominal values).

 

At termination on Day 21 p.c., there were 21, 21, 23 and 22 dams with live fetuses in the control, 100, 300 and 1000 mg/kg/day groups, respectively.

 

There were no unscheduled deaths. There were no relevant effects of the test item treatment on pregnant female data (mean body weight, mean net body weight change, necropsy, hysterectomy,mean gravid uterus weight), with the exception of a slight and transient non-adverse decrease in mean food consumption at 1000 mg/kg/day at the very beginning of the treatment period. Ptyalism and reflux at dosing recorded at 1000 mg/kg/day in 4/24 and 1/24 females, respectively, were considered to be of minor toxicological significance.

 

There were no toxicologically significant findings at fetal examination (sex ratio, mean fetal weight and external, visceral and skeletal observations).

 

In conclusion, on the basis of the results obtained in this study:

-      the No Observed Adverse Effect Level (NOAEL) for maternal parameters was considered to be 1000 mg/kg/day,

-      the NOAEL for embryo-fetal development was considered to be 1000 mg/kg/day.The treatment with the test item induced no developmental toxicity.

Based on the results of this study, the test substance Rhodiastab 55P is not classified for developmental toxicity / teratogenicity according to the classification criteria of the Regulation (EC) 1272/2008 (CLP) and of the Directive 67/548/EEC.