2-Octen-1-ylsuccinic anhydride, mixture of cis and trans

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: OECD 421

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EPS OPPTS 870:3500

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

90277-08-2

IUPAC Name:

90277-08-2

Test material form:

other: liquid

Details on test material:

Name: Tripropenyl succinic anhydride
CAS No.: 92077-08-2
Batch No.: ESD0010823
Chemical Name: dihydro-3-(tripropenyl)furan-2,5-dione
pH: 1-2
Physical State at RT: liquid
Density: 1.01 g/cm3 (20°C, DIN 51757)
Colour: yellow to brown
Expiry Date: 01.12.2012
Storage Conditions: at room temperature
Safety Precautions: The routine hygienic procedures were sufficient to assure personnel health and safety.

Test animals

Species:

rat

Strain:

Wistar

Details on test animals or test system and environmental conditions:

Test System:
Species/strain: Crl: WI(Han): Wistar rats (Full-Barrier)
Source: e.g. Charles River, 97633 Sulzfeld, Germany
Sex: Males and non-pregnant nulliparous females
Age at the beginning of the study: 10-11 weeks old
Body weight at the beginning of the study: interval within ± 20% of the mean weight.
The range of the body weight was:
Females: 173-200g, (mean: 189.18 ± 20%= 37.84 g)
Males: 290-325g, (mean: 303.83 g, ± 20%= 60.77 g)

Number of animals: 10 Males and 10 females per group
The animals were derived from a controlled full barrier maintained breeding system (SPF). According to Art. 9.2, No.7 of the German Act on Animal Welfare the animals are bred for experimental purposes.

Housing and Feeding Conditions:
After an adequate acclimatisation period (at least five days) the animals were barrier maintained (full-barrier) in air conditioned rooms under the following conditions:
- Temperature: 22 ± 3 °C
- Relative humidity: 55 ± 10%
- Artificial light, sequence being 12 hours light, 12 hours dark
- Air change: 10 x / hour
- Free access to Altromin 1324 maintenance diet for rats and mice (Lot No.0906)
- Free access to tap water, sulphur acidified to a pH of approximately 2.8 (drinking water, municipal residue control, microbiol. controlled periodically)
-housed individually in IVC cages (except during the mating period when one female was paired with one male), type III H, polysulphone cages on Altromin saw fibre bedding (Lot No.030512)
Certificates of food, water and bedding are filed at BSL BIOSERVICE.
Test System:
Species/strain: Crl: WI(Han): Wistar rats (Full-Barrier)
Source: e.g. Charles River, 97633 Sulzfeld, Germany
Sex: Males and non-pregnant nulliparous females
Age at the beginning of the study: 10-11 weeks old
Body weight at the beginning of the study: interval within ± 20% of the mean weight.
The range of the body weight was:
Females: 173-200g, (mean: 189.18 ± 20%= 37.84 g)
Males: 290-325g, (mean: 303.83 g, ± 20%= 60.77 g)

Number of animals: 10 Males and 10 females per group
The animals were derived from a controlled full barrier maintained breeding system (SPF). According to Art. 9.2, No.7 of the German Act on Animal Welfare the animals are bred for experimental purposes.

Housing and Feeding Conditions:
After an adequate acclimatisation period (at least five days) the animals were barrier maintained (full-barrier) in air conditioned rooms under the following conditions:
- Temperature: 22 ± 3 °C
- Relative humidity: 55 ± 10%
- Artificial light, sequence being 12 hours light, 12 hours dark
- Air change: 10 x / hour
- Free access to Altromin 1324 maintenance diet for rats and mice (Lot No.0906)
- Free access to tap water, sulphur acidified to a pH of approximately 2.8 (drinking water, municipal residue control, microbiol. controlled periodically)
-housed individually in IVC cages (except during the mating period when one female was paired with one male), type III H, polysulphone cages on Altromin saw fibre bedding (Lot No.030512)
Certificates of food, water and bedding are filed at BSL BIOSERVICE.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

The animals were dosed with the test item on 7 days per week for a period of approximately 54 days. The test item was administered daily during 14 days pre mating and 14 days mating period in both males and in females, and during gestation period and up to post natal day 3 in females. Males were dosed for 28 days.

The test item was administered by gavage using a gavaging canula. The maximum dose volume administered was 4 mL / kg body weight.

For each animal, the individual dosing volume was calculated on the basis of the most recently measured body weight (weekly).

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The analytical method for TSA was received from the sponsor and modified for this study. The method was validated for a concentration range of 10-70 mg/ml in corn oil. Recoveries of all the test samples were between 46 and 153% of nominal. A few samples were analysed a second time to investigate possible errors, resulting in recoveries for all samples as between 78 and 153% of nominal. Analysis was by gas chromatography (GC). Parameters and equipment:
GC: Agilent 6890
Columns: DB-5 MS (30 m*0.25 mm, 0.25 µm film thickness), HP-5 (30 m*0.25 mm, 0.25 µm film thickness)
Carrier gas: Helium 5.0
Split: 20:1
Initial Gas Flow: 2.0 mL/min
Injector Temperature: 250 degrees C.
Injection volume: 1 µl
Column Oven: 40 degrees C (2 min), ramp: 30 degrees C per min to 290 degrees C (3 min).
Detector: MS
Run time: 13.33 min. The test item eluted as a set of peaks at approximately 7.5 min and 7.9 minutes.
Source Temp: 230 degrees C
Ions monitored: 109.2, 124.3 and 195.2 amu
Documentation: exact chromatographic conditions are documented in the raw data and final report.

Stock solution: 100.13 mg of test item was weighed precisely into a 100 ml volumetric flask and filled with acetone to obtain a clear colourless solution.
Standards: Appropriate amount of the stock solution were diluted with acetone to obtain 6 calibration standards ranging from 50 to 500 mg test item/L.
Fortified samples were prepared in a similar manner and diluted with corn oil instead of acetone. Five replicates and two blanks were prepared and analysed.

Sample preparation: Specimens were taken out of the freezer and allowed to thaw at room temperature and the total weight was recorded. The specimens were homogenised by vortexing. Each was transferred entirely into a volumetric flask (50 ml) and the volume brought to the mark with acetone. It was observed that after a while in some of the samples small amounts of precipitate had formed. The sample solutions were further diluted with acetone and then analysed. Each specimen was analysed at lease once. Six specimens were analysed two or three times.

Quantification: The external standard method was used. Measured samples were quantified by measuring the peak area with reference to the calibration curve of the standard solutions.

LOD: The Limit of Detection (LOD) of the method is defined as the lowest concentration having a peak height equivalent to or better than three times the baseline noise.
LOQ: The Limit of Quantification (LOQ) of the method was determined as the lowest fortification level at which acceptable recovery (70 to 110% of nominal) was obtained.

Regression Coefficient: at least 0.09988
Detection Limit: 1.59 mg test item/L.
Quantitation limit: 10 mg test item/ml after dilution by a factor of approximately 100.
Repeatability: Two standard solutions were injected 5 times and the response factor was calculated. The relative standard deviation was 1.7% and 1.2 %, respectively.
Mean recovery rate: at 10 mg/ml: 93 % of nominal (n=8; SD=12%).
at 35 mg/ml: 95 % of nominal (n=9; SD=2%).
at 70 mg/ml: 95 % of nominal (n=5; SD=2%).

Details on mating procedure:

Animal were paired in the ratio of 1:1 (male to female). The subsequent morning and the next morning there onwards the vaginal smears of the females were checked to confirm the evidence of mating. The day of vaginal plug and/or sperm was considered as day 0 of gestation.

Duration of treatment / exposure:

7 days/week.

Frequency of treatment:

daily

Duration of test:

28 days for males, 54 days for females

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

Number and Sex of the Animals:
80 animals (40 males and 40 females) were included in the study (10 male and 10 female animals per group). The study included three dose groups (LD, MD and HD) and one control group (C).

Preparation of the Animals:
Prior to the start of the treatment period a detailed clinical observation outside the home cage was made. Animals were healthy and none of them showed any pathological signs before the first administration. Before the first administration, all animals to be used for the study were weighed and assigned to the experimental groups with achieving a most homogenous variation in body weight throughout the groups of males and females. The animals were acclimatised for at least five days before the first dose administration.

Experimental group and Dosage:
In consultation with the sponsor and based on the a BSL dose range finding study, doses levels of 50, 150, 250 were selected for the 3 dose groups (LD, MD and HD) and 1 control group (C)

The animals in the control group were handled in an identical manner to the dose group subjects and received corn oil in the same volume as used for treatment groups.

Administration of Doses:
The animals were dosed with the test item on 7 days per week for a period of approximately 54 days. The test item was administered daily during 14 days pre mating and 14 days mating period in both male and in female, during gestation period and up to post natal day 3 in females. Males were dosed for 28 days.
The test item was administered by gavage using a gavaging canula. The maximum dose volume administered was 4 mL / kg body weight.
For each animal, the individual dosing volume was calculated on the basis of the most recently measured body weight.

Mating:
Animal were paired in the ratio of 1:1 (male to female). The subsequent morning and the next morning there onwards the vaginal smear of the females were checked to confirm the evidence of mating. Day of vaginal plug and/or sperm was considered as day 0 of gestation. Cages were arranged in such a way that possible effects due to cage placement was minimised.

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily (and once daily during weekends and holidays) all animals were observed for morbidity and mortality. Pertinent behavioural changes, signs of difficult or prolonged parturition and all signs of toxicity were recorded.

DETAILED CLINICAL OBSERVATIONS: No functional test batteries were undertaken.

BODY WEIGHT: Yes
The body weight of all animals was recorded once before assignment to the experimental groups and on the first day of administration.
In the male animals, the body weight was taken weekly during the entire study period and on day of terminal sacrifice.
In the female animals the body weight were taken weekly during the pre-mating period, on gestation day 0, 7, 14, 20 and on post-natal day 0 (within 24 hours of parturition) and post-natal day 4 along with pups.

FOOD CONSUMPTION AND COMPOUND INTAKE : Yes. Food consumption was measured on the corresponding day of the body weight measurements after the beginning of the dose administration. Food consumption was not measured during the mating period and post mating period in males.
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No

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

POST-MORTEM EXAMINATIONS: Yes
Males were sacrificed after the completion of mating period (total dosing of 28 days) and females were sacrificed on respective post natal day 4 along with pups by using high dose of Ketamine/Xylazine (2:1). At the time of sacrifice or death during the study, the adult animals were examined macroscopically for any abnormalities or pathological changes. Special attention was paid to the organs of the reproductive system.
Pups sacrificed on day 4 post-partum were carefully examined for gross external abnormalities.
The number of implantation sites and corpora lutea was recorded in all pregnant females by gross observations.

The ovaries, uterus with cervix, vagina, testes, epididymides, accessory sex organs (prostate, seminal vesicles with coagulating glands as a whole) were preserved in 10 % neutral buffered formalin. Testes and epididymides were initially preserved in modified Davidson’s Solution for approximately 24 hours and transferred to 10 % neutral buffered formalin.

Additional organs of animals which died during the course of the study were preserved and examined histopathologically in order to determine the cause of death.

OTHER:
A full histopathological evaluation (after the preparation of paraffin sections and haematoxylin-eosin staining) was carried out on all animals of the control and high dose groups which are sacrificed at the end of the treatment period.
Histopathological examinations were not extended to animals of the other dose groups, as no treatment-related changes were observed in the high dose group.
A detailed qualitative examination of the testes was made taking into account the tubular stages of the spermatogenic cycle at the evaluation of additional haematoxylin-PAS (Periodic Acid Schiff) stained slides.
Gross lesions macroscopically identified were examined microscopically.
The histological processing of tissues to microscope slides were performed at the GLP-certified contract laboratory Propath UK Ltd, Willow Court, Netherwood Road, Hereford HR2 6JU, Great Britain (test site for tissue processing). The histopathological evaluation was performed at the GLP-certified contract laboratory KALEIDIS- Consultancy in Histopathology (test site for histopathology), 6 rue du Gers, 68300 Saint-Louis, France. Blocking, embedding, cutting, H&E staining and scientific slide evaluation was performed according to the corresponding SOP’s of the test sites.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Other: Copulation Index (%), Fertility Index (%) and Delivery Index (%)

Fetal examinations:

- External examinations: Yes:
- Soft tissue examinations: No
- Skeletal examinations: No
- Head examinations: No

Statistics:

A statistical assessment of the results of the body weight, food consumption, litter data and absolute and relative organ weights was performed for each gender by comparing values of dosed with control animals using a one-way ANOVA and a post-hoc Dunnett Test. These statistics were performed with GraphPad Prism V.5.01 software (p<0.05 is considered as statistically significant).

Indices:

Copulation Index (%), Fertility Index (%) and Delivery Index (%)
Offspring Viability Index (%)

Historical control data:

yes, held at laboratory.

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:yes

Details on maternal toxic effects:
Precoital Interval and Duration of Gestation:
No treatment related effect was observed on precoital interval and duration of gestation and values were comparable between the groups. All pregnancies resulted in normal births.

Successful mating resulted in 10, 8, 9 and 3 pregnancies in the control, low, mid and high dose respectively.

Pre and Post Natal Data:
Pre and post-natal data (group mean number of corpora lutea, number of implantation sites, number of pups born on PND 0, percent preimplantation and post implantation loss) remained unaffected due to treatment when compared with controls. However, there was a biologically significant increase in post implantation loss observed in MD group although statistical significance was not achieved. This increase in group mean post implantation loss in MD group could be attributed to the very low number of live pups born and high difference in implantation sites and number of pups born on PND 0 from two MD females (66 and 69). Group mean values from remaining 7 females were comparable to the controls and therefore this increase in post implantation loss in HD group was considered to be non adverse and within the range of biological variation.

Signs of toxicity occurred in both male and females, and mortalities in 250 mg/kg bw/d group females.

Mortality:
In females, 8 animals (71, 72, 73, 74, 75, 77, 78 and 80) from HD group died on premating day 5, 5, 6, gestation day 11, 21, 22, 23 and 21, respectively.

Clinical Observation:
Test item related clinical signs were observed in male and female MD and HD group animals. In females, predominant clinical signs observed were slight salivation (2/10 in LD, 6/10 in MD and HD), moderate salivation (4/10 in MD and HD), slight piloerection (1/10 in C, 6/10 in MD and HD), moderate piloerection (1/10 in MD and 3/10 in HD), moving the bedding (9/10 in MD and 6/10 in HD) and clonic convulsion and tremor (1/10 in HD).

Body Weight and Body Weight Change:
In females, no statistically significant effect on body weight and body weight change was observed throughout the study period in treatment groups. However, a biologically significant decrease in body weight and bodyweight change was observed from gestation day 20 to postnatal day 4 in MD and HD group when compared with controls.

Food Consumption:
In females, statistical analysis of food consumption data revealed no test item related effect on food consumption in treatment groups during entire study period when compared with controls.


Gross Pathology:
In females, predominant gross pathological findings observed in dead animals were white area on left liver lobe (1/10 in HD females), discoloured stomach (3/10 in HD females), gaseous distension of intestinal tract (3/10 in HD females), dark spot on lung (1/10 in HD females), discoloured red thymus (2/10 in HD females) and small thymus (1/10 in HD females). The significance of these macroscopic findings in dead females remains unclear and an influence of beginning of autolysis cannot be excluded.

Organ Weight:
In females, a statistically significant increase in relative kidney weights (left and total) was observed in MD and HD group when compared with controls. However, in the light of histopathological findings in the kidneys, the effect on kidney weights in females was considered to be test item related.

Histopathology
One gavage accident was established as a direct cause of death for one decedent high dose female. In addition, in all decedents combinations of histopathological findings were noted in several of the following organs: kidney, forestomach, lymphoid organs (spleen, thymus, Peyer's patch, mesenteric and axillary lymph node), lung, adrenal gland and heart, and were considered to have contributed to the death of these animals.

Renal tubular degeneration/regeneration was considered to be possibly directly test item-related. Renal effects occurred only in females. In the forestomach, minor (sub)mucosal mixed cell infiltration, submucosal congestion/hemorrhage and (peri)vasculitis were also considered to represent direct effects of the test item. For lymphoid atrophy and single cell death of lymphoid organs, as well as for leukocytostasis and vasculitis/thrombi in the lung, a direct test item relationship was not clear. Adrenal gland changes (cortical degeneration/necrosis and diffuse cortical hypertrophy) and heart changes (cardiomyocyte vacuolation, focal myocardial degeneration) were considered to be secondary.

At terminal sacrifice, the kidney was evaluated in all surviving females. Against a background incidence noted in control females, minimal to moderate numbers of basophilic (regenerative) tubules in the cortex and medulla occurred in the females of all three dose groups, without a clear dose relationship. Renal changes were considered to be possibly directly test item-related.

Altogether, there was no evidence of a direct test item-related effect on male or female reproductive organs in this study.

Effect levels (maternal animals)

Dose descriptor:

NOAEL

Effect level:

50 mg/kg bw/day (nominal)

Based on:

test mat.

Remarks:

verified analytically

Basis for effect level:

other: not specified

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
None observed.
Litter Weight Data:
No statistically significant effect on litter weight data was observed in treatment groups when compared with controls. However, biologically significant decrease in group mean litter weight, total litter weight, male and female litter weight on PND 0 and 4 was observed in MD and HD group when compared with controls.

Litter Data:
Statistical analysis of litter data revealed no treatment related effect on total number of pups born, number of males, number of females, sex ratio, live pups, still birth and runt on PND 0 and number of males, number of females, total number of pups and sex ratio on PND 4.

All group mean and individual values for various litter data parameters from treatment groups were comparable with the controls except high numbers of still births (11) were observed in one female (66) from MD group.

Reproductive Indices:
No treatment related effect on copulation index and delivery index was observed when compared with controls, However, reduced fertility index (No. of pregnant females/No. of copulated females X 100) in HD (42.9) and viability index in MD (86.87) was observed as compared to control and LD groups.

Pup Survival Data:
Survival of the pups from PND 0 to PND 4 remained unaffected due to the treatment in all treatment groups and no pup mortality was observed in this study. However, 1 pup from LD group- female 56 (pup no. 9), 2 pups from MD group female 64 (pup no. 3 and 6), female 66 (pup no. 1 and 2) were missing and presumed to be cannibalized by the dam between PND 0-2. Since this incidence of cannibalism was observed in just 3 females and it was within the rat cannibalism rate, this incidence was not considered to be test item related.

Pup External Finding:

No treatment related gross external findings were observed in pups from any of the treated groups on PND 0 and 4.

Effect levels (fetuses)

Dose descriptor:

NOAEL

Effect level:

> 250 mg/kg bw/day (nominal)

Based on:

test mat.

Remarks:

verified analytically

Basis for effect level:

other: No signs of developmental toxicity in pups up to 250 mg/kg Body weight.

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Repeated dose administration of a category member, tripropenyl succinic anhydride, to groups of 10 male (28 days) and female (maximum 54 days) Wistar rats at dosages of 50, 150 and 250 mg/kg bw/d, revealed mortality, but no significant findings of toxicological relevance in HD group females. Based on the data generated from this reproduction/ developmental toxicity screening test with tripropenyl succinic anhydride, the no observed adverse effect level (NOAEL) for parental animals was considered to be 50 mg/kg body weight and the NOAEL for developmental toxicity of pup was believed to be ≥ 250 mg/kg body weight. Data can be read-across among members of the C8-12 Alkenyl Succinic Anhydrides Category, based on common functional groups, similar break-down products and potency patterns among carbon-chain length. This is adequate to fulfill the information requirements, to be the basis for classification and labelling decisions, and for risk assessment.