Reaction mass of bis(N-decyl-N,N-dimethyldecan-1-aminium) carbonate and N-decyl-N,N-dimethyldecan-1-aminium hydrogen carbonate

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

- Reliability: GLP study according to international guidelines - Read-across justification: As both source (Didecyldimethylammonium chloride, DDAC) and target chemicals (Didecyldimethylammonium carbonate, DDA carbonate) have identical organic cations with hydrophobic side chains - the only difference is the inorganic anion carbonate or chloride with negligible contribution to the hazard properties - both substances can be predicted to have similar movement and fate characteristics.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

1991

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPP 83-3 (Prenatal Developmental Toxicity Study)

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Test material form:

liquid: viscous

Details on test material:

- Name of test material: Didecyldimethylammonium chloride (DDAC)

Test animals

Species:

rat

Strain:

CD-1

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 10 weeks
- Weight at study initiation: males 250 to 300 g; females 175 to 200
- Housing: individually in stainless steel wire mesh cages
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: ca. two weeks

ENVIRONMENTAL CONDITIONS
- Temperature (°F): 66 to 77
- Humidity (%): 40 to 70
- Photoperiod (hrs dark / hrs light): 12 hrs

IN-LIFE DATES:
- From: 05 February 1990
- To: 01 March 1990

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

DIET PREPARATION
- Rate of preparation of diet (frequency): twice during the study

VEHICLE
- Concentration in vehicle: 0.2, 2.0 and 4.0 mg/mL
- Amount of vehicle: 5.0 mL/kg bw

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Standard solutions used for analyses were prepared as follows. A standard stock solution (1.0 mg/mL) was prepared by weighing 0.0619 g of test substance into a 50 mL volumetric flask and diluting to volume with acetonitrile. The 1.0 mg/mL standard was then appropriately diluted with acetonitrile to generate standard solutions of 10, 50 and 100 ng/μL. An aliquot of each dosing formulation was diluted with acetonitrile as described above. One (1.0) μL of each diluted dosing solution was analyzed for test substance content. All dosing samples were analyzed with a Hewlett-Packard 5880A Gas Chromatograph equipped with a Nitrogen Phosphorous detector. The formulations and analyses were based on actual test item content.
The dosing solutions were homogeneous, stable for at least 12 days when stored at room temperature, and within 97.0 to 103.8 % of nominal. Formulations were based on actual test item content of the test material. No test substance was detected in the control solutions at minimum detection limit of approximately 0.01 mg/mL.

Details on mating procedure:

- Impregnation procedure: cohoused
- M/F ratio per cage: 1:1
- Length of cohabitation: 05 to 08 Februar 1990
- Verification of same strain and source of both sexes: yes
- Proof of pregnancy: vaginal plug

Duration of treatment / exposure:

Timed-pregnant CD® (Sprague-Dawley) rat dams Were dosed daily with test item in vehicle or vehicle alone (Millipore® water) on gd 6 through 15. All treatments were administered by gavage using a 16 gauge stainless steel dosing tube, 3.0 inches long (Perfektum®, Popper and Sons, Inc., New Hyde Park, NY), attached to a 3.0 cc disposable syringe. The dose volume employed was 5.0 mL/kg body weight. Administered volumes were adjusted on the basis of the most recent body weight of each animal.
All females on study were weighed on gd 0, 6 (prior to onset of dosing), 9, 12, 15 (during the dosing period), 18 and 21. Food consumption was measured at three-day intervals throughout gestation (gd 0-21). All females were thoroughly examined daily for clinical signs of toxicity (twice daily during the dosing period). In addition, the animals were examined twice daily for mortality and morbidity.

Frequency of treatment:

Once daily during exposure period

Duration of test:

Days 6-15 of gestation

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 1, 10 and 20 mg/kg bw/day
Basis:
nominal conc.

No. of animals per sex per dose:

25 females/group

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The dose levels of 0.0, 1.0, 10.0 and 20.0 mg/kg bw/day were selected based on information from a dose range-finding study on pregnant rats

Examinations

Maternal examinations:

The gravid uterus, ovaries (including corpora lutea), cervix, vagina, and abdominal and thoracic organs and cavities were examined grossly. The lumen and lining of the esophagus, stomach and trachea were examined for any indications of irritation from the dosing solutions and for dosing errors. No females exhibited evidence of dosing error.
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily during dosing, daily thereafter

BODY WEIGHT: Yes
- Time schedule for examinations: Days 0, 6, 9, 12, 15, 18 and 21

FOOD CONSUMPTION AND COMPOUND INTAKE: Yes
- Time schedule: Three day intervals

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day #: All surviving study females were sacrificed on gd 21 by carbon dioxide asphyxiation. The sacrifice period was February 27 through March 1, 1990.
- Organs examined: The maternal body cavities were opened by a mid-sagittal thoracolaparotomy. The gravid uterus, ovaries (including corpora lutea), cervix, vagina, and abdominal and thoracic organs and cavities were examined grossly. The lumen and lining of the esophagus, stomach and trachea were examined for any indications of irritation from the dosing solutions and for dosing errors. No females exhibited evidence of dosing error.

Ovaries and uterine content:

Ovarian corpora lutea of pregnancy were counted. The uterus was externally examined for signs of hemorrhage, removed from the abdominal cavity, weighed, and dissected longitudinally to expose the contents. All live and dead fetuses and resorption sites (early and late) were noted and recorded. Uteri from females that appeared nongravid were placed in a 10 % ammonium sulfide solution for detection of early resorptions (Salewski, 1964). Maternal liver weights also were determined.

Fetal examinations:

All live fetuses were weighed, sexed, examined for external malformations including cleft palate, and variations. Approximately one half of the fetuses in each litter (even-numbered fetuses from litters with an even number of live fetuses, odd-numbered fetuses from litters with an odd number of liver fetuses) were examined for visceral (thoracic and abdominal) abnormalities by modification of methods described by Staples (1974). These fetuses were then decapitated and their heads fixed in Bouin's solution for examination of craniofacial structures by sectioning methods modified from Wilson (1965, 1973). All sectioned heads were saved after examination. The remaining half of fetuses in each litter (intact) were eviscerated and processed for skeletal staining with alizarin red S (Crary, 1962) and examined for skeletal malformations and variations. Following skeletal examination, skeletal preparations from all fetuses were bagged individually and all fetuses within each litter were bagged together. The skeletons of the fetuses subjected to visceral examinations and decapitated Were also stained and stored, but were not examined.

Statistics:

Levene’s test for equal variances, analysis of variance, and t-tests with Bonferroni probabilities for pairwise comparisons. Nonparametric data were analyzed with Kruskal-Wallis test followed by Mann-Whitney U test when appropriate. Incidence data were compared using Fisher’s Exact Test.

Indices:

No data

Historical control data:

Historical data on 2,452 control CD® litters have been summarized across teratology studies from nine pharmaceutical companies or research organizations by the Middle Atlantic Reproduction and Teratology Association (Woo and Hoar, 1979).

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:yes

Details on maternal toxic effects:
- Clinical signs: Audible respiration and gasping at 20 mg/kg bw/day. Audible respiration at 10 mg/kg bw/day
- Mortality: No mortalities
- Body weight gain: Reduced body weight gain at 20 mg/kg bw/day
- Food consumption: Reduced food consumption at 20 mg/kg bw/day
- Gross findings at necropsy: Ulceration of stomach and gas filled intestines at 20 mg/kg bw/day. Gravid uterine and liver unaffected.
- Other: No abortions or early births

No dams died, aborted, delivered early or were removed from the study. At scheduled laparotomy one (1) dam each at 1.0 and 10.0 mg/kg bw/day and two (2) dams at 20.0 mg/kg bw/day were not pregnant. All pregnant dams had one or more live fetuses at scheduled sacrifice (no litters were fully resorbed).
Twenty-three (23) to 25 litters per group were available for examination at scheduled sacrifice. All subsequent presentation and discussion of summary data are based on pregnant animals.
Treatment-related clinical signs of toxicity observed during the treatment period included audible respiration and gasping at 20.0 mg/kg bw/day and audible respiration at 10.0 mg/kg bw/day. At 20.0 mg/kg bw/day, audible respiration was observed subsequent to the treatment period as well.
While not statistically significant, there appears to be a treatment-related reduction in maternal body weight for Days 12, 15, 18 and 21 at 20 mg/kg bw/day. Body weight gains also appeared to be decreased for Days 9 to 12, 12 to 15 and 6-15 at 20 mg/kg bw/day, and body weight gains appear reduced for the entire gestational period, Day 0-21. There were no apparent changes in body weight or weight gain at 10.0 and 1.0 mg/kg bw/day. Apparent reductions in food consumption at 20 mg/kg bw/day for Days 9 to 12, 12 to 15 and 6 to 15 correlate well with reductions in body weight and severity of clinical signs during the treatment period. Food consumption at 10.0 and 1.0 mg/kg bw/day was equivalent across groups during and subsequent to the treatment period.
Necropsy observations in dams sacrificed on gd 21 were recorded. Treatment-related findings included ulceration of the stomach and gas-filled intestines at 20.0 mg/kg bw/day.
Slight treatment-related reductions on maternal terminal body weight corrected weight change were observed at 20.0 mg/kg bw/day. Gravid uterine weight and liver weight were unaffected by treatment.
Gestational parameters including the number of corpora lutea, total implants, viable and nonviable implants, pre- and post implantation loss and sex ratio (% male fetuses) per litter were equivalent among groups. Fetal body weight per litter was unaffected by test substance treatment.

Effect levels (maternal animals)

1

Dose descriptor:

NOAEL

Effect level:

1 mg/kg bw/day

Based on:

act. ingr.

Basis for effect level:

other: maternal toxicity

2

Dose descriptor:

NOEL

Effect level:

20 mg/kg bw/day

Based on:

act. ingr.

Basis for effect level:

other: developmental toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
- Bodyweight: No treatment-related effects
- Gross findings at necropsy: No malformations
- Skeletal findings: No treatment-related variations or malformations
- Visceral findings: No treatment-related variations or malformations

There were no treatment-related increases in individual external, visceral or skeletal fetal malformations, in malformations by category or in total malformations in this study. There were no differences in the incidences of external and visceral variations were observed between control and treated groups. The incidence of two skeletal variations, poorly ossified cervical centrum #7 and majority of proximal hindlimb phalanges unossified, were significantly decreased in the 10.0 and 20.0 mg/kg bw/day dose groups, respectively. These reduced incidences were not considered to be related to test substance administration. The incidences of variations by category (external, skeletal or visceral) and total variations were not significantly altered by test substance administration.

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Test item administered by gavage during organogenesis to CD® (Sprague-Dawley) rats produced characteristic clinical signs of maternal toxicity (rapid respiration and gasping) at 10.0 and 20.0 mg/kg bw/day and reductions in body weight and food consumption at 20.0 mg/kg bw/day. No evidence of developmental toxicity including teratogenicity was observed at any dose employed. The A/D ratio (the ratio of the adult lowest observable effect level to the developmental lowest observable effect level) is less than 1 (10 mg/kg bw/day:at least 20 mg/kg bw/day) indicating no preferential susceptibility of the rat conceptus to the test substance under the conditions of this study.
The "no observable effect level" for maternal toxicity was 1.0 mg/kg bw/day; the NOEL for developmental toxicity was at least 20.0 mg/kg bw/day.

Executive summary:

A study was carried out according to OECD Guideline 414 (Prenatal Developmental Toxicity Study) and EPA OPP 83-3 (Prenatal Developmental Toxicity Study) using the structural analog Didecyldimethylammonium chloride (DDAC). In view of the chemical and structural similarities (the relevant chemical part of both, DDAC and DDACarbonate, under the conditions of this test is the common quaternary ammonium cation Didecyldimethylammonium+), it is considered that the data are adequate for DDACarbonate. Timed-pregnant CD® (Sprague-Dawley) rats were exposed to test item in deionized water by gavage on gestational days (gd) 6 through 15. Twenty-five (25) copulation plug-positive females per group were dosed with doses of 1.0, 10.0 and 20.0 mg/kg bw/day. The dose volume employed was 5.0 mL/kg of body weight based on the most recent body weight of each female. The vehicle control group (0.0 mg/kg bw/day) of twenty-five females received deionized water at a volume of 5.0 mL/kg bw/day. Clinical observations were taken daily (twice daily during dosing) and maternal body weights were recorded for all study females on gd 0, 6, 9, 12, 15, 18, and 21. Maternal food consumption was measured at three-day intervals throughout gestation, gd 0-21. At scheduled sacrifice on gd 21, the dams were evaluated for body weight, liver and gravid uterine weight, number of corpora lutea and number and status of implantation sites (i.e. early and late resorptions, dead fetuses, live fetuses). All live fetuses were dissected from the uterus, counted, sexed, weighed, and examined for external maformations (including cleft palate) and variations. Approximately one-half of the fetuses in each litter were examined for visceral (including craniofacial) malformations and variations. The remaining one-half of the fetuses were evaluated for skeletal malformations and variations. No females died, aborted, delivered early or were removed from study. Pregnancy rate was approximately equivalent across groups ranging from 92 % to 100 %. All surviving pregnant females had one or more live fetuses at scheduled sacrifice, and 23 to 25 litters were examined at each dose. Maternal toxicity was indicated at 10.0 and 20.0 mg/kg bw/day by characteristic clinical signs of audible respiration. At 20 mg/kg bw/day, gasping was observed during the dosing period and audible respiration persisted subsequent to treatment. Reductions in body weight and food consumption were observed at 20.0 mg/kg bw/day during the treatment period. Maternal terminal body weight and corrected weight change were reduced at 20.0 mg/kg bw/day. There were no effects on maternal gravid uterine weight, liver weight or relative liver weight. Treatment-related necropsy findings in dams at scheduled sacrifice included ulceration of the stomach and gas-filled intestines at 20.0 mg/kg bw/day. Gestational parameters, including ovarian corpora 1utea of pregnancy, implantations per litter (viable, nonviable and total), sex ratio and fetal body weight per litter were not affected by treatment. There were no significant treatment-related external, visceral or skeletal malformations observed in this study. There were no increased incidences of external, visceral or skeletal fetal variations. Administration of didecy1dimethy1ammoniumch1oride by gavage to CD® (Sprague-Dawley) rats during organogenesis resulted in characteristic signs of maternal toxicity at 10.0 and 20.0 mg/kg bw/day including audible respiration and gasping during the treatment period at 10.0 and 20.0 mg/kg bw/day and reduced body weight and food consumption at 20.0 mg/kg bw/day. No treatment-related developmental toxicity, including teratogenicity, was observed at any dose 1eve1. The "no observed effect level" (NOEL) for maternal toxicity was 1.0 mg/kg bw/day. The NOEL for developmental toxicity was at least 20.0 mg/kg bw/day.