Cyclododeca-1,5,9-triene

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Remarks:

based on test type (migrated information)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

2000

Reference 2

Reference Type:

publication

Title:

Reproductive and repeated dose toxicity of cyclododecatriene (CDDT) in rats following oral (gavage) treatment.

Author:

Malley LA, Everds NE, Makovec GT and Kennedy GL jr.

Year:

2002

Bibliographic source:

Drug Chem. Toxicol. 25 (2), 149-170.

Reference 3

Reference Type:

publication

Title:

Robust summary for 1,5,9-cyclododecatriene (revised).

Author:

DuPont Safety, Health & Environmental Excellence Center, Wilmington (Del., USA)

Year:

2003

Bibliographic source:

U.S. EPA, 46 pp

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

1,5,9-cyclododecatriene

IUPAC Name:

1,5,9-cyclododecatriene

Details on test material:

1,5,9-cyclododecatriene, purity 99.86%

Test animals

Species:

rat

Strain:

other: Crl:CD (SD)IGS BR

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ORGANISMS
- Age: males 59 days, females 52 days (approximately)

Administration / exposure

Route of administration:

oral: gavage

Details on exposure:

ADMINISTRATION / EXPOSURE
- Vehicle: corn oil
- Concentration in vehicle: 6, 20, 60 mg/ml
- Total volume applied: 5 ml/kg bw/dose

Details on mating procedure:

MATING PROCEDURES: 
- mating period approximately 1-2 weeks, beginning after  approximately four weeks of dosing.

Duration of treatment / exposure:

Exposure period: males through test day 55; females 4 weeks premating through 4-day lactation period
Premating exposure period (males): approximately 4 weeks
Premating exposure period (females): approximately 4 weeks
Duration of test: approximately 60 days

Frequency of treatment:

daily

Doses / concentrations

Remarks:

Doses / Concentrations:
30, 100, 300 mg/kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

Number of animals: 10 per sex and per dose group

Control animals:

yes, concurrent vehicle

Examinations

Parental animals: Observations and examinations:

- Clinical signs: at least once daily
- Mortality: at least twice daily
- Body weight: weekly, for females also on lactation days 0 and 4
- Food consumption: weekly
- Ophthalmoscopic examination: Both eyes of all rats prior to study and  on test day 24, prior to clinical pathology evaluation (surviving rats).
- Clinical pathology evaluation on all rats after 4 weeks of dosing, and  on male rats at the time of scheduled sacrifice:   
- hematology / coagulation: erythrocyte count, total leukocyte count,  platelet count, hemoglobin concentration, hematocrit, differential  leukocyte count, mean corpuscular volume, mean corpuscular hemoglobin,  mean corpuscular hemoglobin concentration, absolute reticulocyte counts,  red cell distribution width, microscopic blood examination, activated  partial thromoboplastin time, prothrombin time.   
- clinical chemistry: alkaline phosphatase, alanine aminotransferase,  aspartate aminotransferase, sorbitol dehydrogenase, glucose, urea  nitrogen, calcium, inorganic phosphorus, total bilirubin, cholesterol,  triglyceride, creatinine, total protein, albumin, globulin, sodium,  potassium, chloride.  
- urine: volume, specific gravity, urobilinogen, blood, glucose,  protein, appearance (quality, transparency, color), pH, bilirubin,  ketones, sediment microscopy.
- Other: Neurobehavioral Functional Observational Battery (FOB) on all  study rats prior to exposure and following approximately 4 weeks of test  substance administration.

Litter observations:

OFFSPRING: gestation length, mating index, gestation index, fecundity  index, implantation site numbers, implantation efficiency, sex ratio,  pups born alive, viability index

Postmortem examinations (parental animals):

ORGANS EXAMINED AT NECROPSY (MACROSCOPIC AND MICROSCOPIC):
- Time: Sacrifice and necropsy of males on day 56 and of females on days  56-64.
- Organ weights P: liver, kidneys, adrenal glands, thymus, brain, spleen,  heart, testes, epididymides. Calculation of ratios to final body and  brain weights.
- Histopathology P:    all high dose and control rats: testes, epididymides, ovaries, gross  lesions;   5 high dose and 5 control rats per sex: additional 37 tissues   5 females from other groups with >= 1 offspring: liver

Postmortem examinations (offspring):

Implantation site number and efficiency, sex ratio, mean pup weights, pups born alive,  viability index

Statistics:

STATISTICAL METHODS: 
- All weight parameters (P, not F), gestation length, clinical pathology,  grip strength, foot splay: One-way analysis of variance followed with  Dunnett's test or Kruskal-Wallis test; followed with Dunn's test.
- Incidence of clinical and FOB observations; mating, gestation,  fecundity indexes: Sequential application of Cochran-Armitage test for  trend
- Implantation site number and efficiency, sex ratio, pups born alive,  viability index: Jonckheere's test
- Mean pup weights: Linear contrast of the least square means
- Motor activity: Levene's and Shapiro-Wilk tests followed by repeated  measures analysis of variance followed by contrasts of Jonckheere's trend  test.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Other effects:

not examined

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Details on results (P0)

- Number of deaths at each dose:    One high-dose male was sacrificed in extremis due to a dosing-related  injury.   One high-dose female was found dead on day 57 from dystocia.   No other deaths occured during the study.

- Body weight:   Decreased body weight gain was observed and considered to be  compound-related and of biological significance:   300 mg/kg males (-19 % for days 1-56, not statistically significant;  weight -7%);   100 and 300 mg/kg females (only during gestation: gains -13% and -20%,  weights -7% and -12%, respectively, statistically significant).   

- Food/water consumption: Increased food consumption was observed and  considered to be compound-related and of biological significance:   300 mg/kg males (+19%)   100 mg/kg (+7%, not statistically significant) and 300 mg/kg females  (+13%, statistically significant) during gestation.   As a consequence, food efficiency was significantly reduced:   300 mg/kg males (-33%)   100 and 300 mg/kg females during gestation (+14 and +29%, respectively,  statistically significant).

- Ophthalmoscopic examination: no test substance-related effects
- Description, severity, time of onset and duration of clinical signs:  There were no test substance-related effects on clinical observations as  well as in neurobehavioral parameters or motor activity.
- Fertility index: no test substance-related effects
- Duration of gestation: no test substance-related effects
- Gestation index: no test substance-related effects
- Hematological findings incidence and severity: no test  substance-related effects
- Clinical biochemistry findings incidence and severity: no test  substance-related effects
- Gross pathology incidence and severity: no test substance-related  effects
- Number of implantations: no test substance-related effects
- Organ weight changes: no test substance-related adverse effects.   
- Liver weights were statistically significantly increased in several  dosed groups:   Males: 30 mg/kg +10% relative; 100 mg/kg +14 % absolute, +21% relative;  300 mg/kg +34 % absolute, +45% relative.   Females: 100 mg/kg +15% relative; 300 mg/kg +36% absolute, +42%  relative.   In females it was associated with microscopic centrilobular  hepatocellular hypertrophy, which is indicative of a physiological  response-induction of enzymes associated with metabolism, and is not  considered biologically adverse.   In males, minimal diffuse hypertrophy may have occurred, which is hard  to identify histologically.   
- Kidney weights were statistically significantly increased in several  dosed groups:   Males: 100 mg/kg +16% absolute, +21% relative; 300 mg/kg +22%, +37%  relative   Females: 100 mg/kg +11% relative; 300 mg/kg +15% absolute, +17% relative   These findings were associated with some evidence of diuresis in  high-dose males and females, but there were no compound-related changes  in any other kidney parameter including histopathology.
 These weight  changes may be an adaptive response to the physiological changes that  occur following administration of large doses of a test material. They  were not considered to be biologically adverse.
- Histopathology incidence and severity: no test substance-related  adverse effects
- Other observations   Mating index: no test substance-related effects; Implantation efficiency: no test substance-related effects  

Effect levels (P0)

1

Dose descriptor:

NOAEL

Effect level:

30 mg/kg bw/day

Sex:

female

Basis for effect level:

other: Decreased of bodyweight gain in female rats were observed at 100 and 300 mg/kg bw/d.

2

Dose descriptor:

NOAEL

Remarks:

(fertility)

Effect level:

300 mg/kg bw/day

Sex:

male/female

Basis for effect level:

other: No effect on fertility was observed at any doses.

Remarks on result:

other: Generation not specified (migrated information)

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not examined

Histopathological findings:

not examined

Details on results (F1)

- Body weights of pups in the 300 mg/kg group were significantly  decreased (-17% on lactation day 4)
- Sex and sex ratios: no test substance-related effects
- Viability index: no test substance-related effects
-  Pups born alive: no test substance-related effects

Effect levels (F1)

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

100 mg/kg bw/day

Basis for effect level:

other: Decreased of pup bodyweight was observed at 300 mg/kg bw/d on lactation day 0 and 4.

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

Summary of reproductive outcomes:

- Dose (mg/kg) 0 30 100 300

- Mating Index(%): 80.0 90.0 100.0 100.0

- Fertility Index (%): 87.5 77.8 70.0 70.0

- Gestation Length (days): 22.0 22.0 22.0 22.0

- Implantations (mean/litter): 16.0 15.6 16.3 16.1

- Implantation efficiency (%): 92.1 96.2 92.0 89.5

- Gestation Index: 100.0 100.0 100.0 100.0

- Mean % Born Alive: 98.3 99.1 99.2 99.0

- 0-4 Day Viability (%): 98.0 99.0 98.2 98.3

- Sex Ratio (males): 0.45 0.50 0.49 0.45

Applicant's summary and conclusion

Conclusions:

Based the resuls of this study, the NOAEL for maternal toxicity was 30 mg/kg bw/d based on decreased on bodyweight gain, the NOAEL for reproductive performance (fertility) was 300 mg/kg bw/d because no effect was observed in this study; and the NOAEL for developmental study was 100 mg/kg bw/d because pup bodyweightd were significantly decreased on lactation days 0 and 4 at 300 mg/kg bw/d.

Executive summary:

Following the 4-week premating period, each female was paired with a male of the same dosage group during a 1-2 week mating period. Measurements of body weight, food consumption, food efficiency, and clinical signs of toxicity in females were conducted weekly during gestation and on lactation days 0 and 4. At the end of an approximately 3-week post- mating period, surviving males

and presumed nonpregnant females were sacrificed, and on lactation day 4, lactating females and offspring were sacrificed. Ten organs were weighed, and 40 tissues were preserved for microscopic examination. The testes, epididymides, ovaries, and gross lesions from all high-dose and control group rats were examined microscopically. All other preserved tissues from 5 male and 5 female rats, randomly selected from the high-dose and control groups were examined microscopically. Livers from 5 randomly

selected female rats in the 30 and 100 mg/kg/day groups that delivered at least 1 live offspring were also examined microscopically. Offspring were weighed and evaluated for clinical abnormalities. Reproductive parameters recorded or calculated included gestation length, mating index, gestation index, fecundity index, implantation site numbers, implantation efficiency, sex ratio, pups born alive, and

viability index.

There were no test substance-related effects on reproductive parameters, which included gestation length, mating index, gestation index, fecundity index, implantation site numbers, implantation efficiency, sex ratio, pups born alive, and viability index. There any no changes in neurobehavioral parameters, or motor activity.

There were no test substance-related effects on clinical observations, number of pups born, number of pups born alive, or number of pups surviving through lactation day 4. Body weights of pups in the 300 mg/kg/day group were significantly decreased on lactation days 0 and 4.

Based the resuls of this study, the NOAEL for maternal toxicity was 30 mg/kg bw/d based on decreased on bodyweight gain, the NOAEL for reproductive performance (fertility) was 300 mg/kg bw/d because no effect was observed in this study; and the NOAEL for developmental study was 100 mg/kg bw/d because pup bodyweightd were significantly decreased on lactation days 0 and 4 at 300 mg/kg bw/d.