Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Study period:
24 July 2020 to 10 November 2020
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2021
Report date:
2021

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)
Limit test:
no

Test material

1
Chemical structure
Reference substance name:
Benzenesulfonic acid, 4-C10-13-alkyl derivs.-, salts with amines, C16-C18 (even numbered) alkyl
Molecular formula:
[(CnH2n+1)NH3+].[(CxH2x+1)-C6H4-S03-]
IUPAC Name:
Benzenesulfonic acid, 4-C10-13-alkyl derivs.-, salts with amines, C16-C18 (even numbered) alkyl
Test material form:
liquid: viscous
Details on test material:
Chemical registery number : 953-378-2
Chemical name : Benzenesulfonic acid, 4-C10-13-alkyl derivs.-, salts with amines, C16-C18 (even numbered) alkyl

Based on the qualitative and quantitative information on the composition, the sample used are representative of the boundary composition shared and agreed by each registrant.

Test animals

Species:
rat
Strain:
Crj: CD(SD)
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River (UK) Ltd
- Age at study initiation: 77 to 83 days old
- Weight at study initiation: 233 to 287 g
- Housing: One female per cage during gestation. Cages comprised of a polycarbonate body with a stainless steel mesh lid.
- Diet: SDS VRF1 Certified pelleted diet ad libitum
- Water: Potable water from the public supply ad libitum
- Acclimation period: Six days before commencement of pairing

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24°C
- Humidity (%): 40-70%
- Air changes: Filtered fresh air which was passed to atmosphere and not recirculated
- Photoperiod (hrs dark / hrs light): 12 hours light: 12 hours dark

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
Method of preparation: The test item was initially warmed in a water bath at 35°C until fully melted.
A series of formulations at the required concentrations were prepared by the addition of individual weighings of the test item with the required volume of the vehicle whilst magnetically stirring. The formulations were then transferred into final containers using a syringe, whilst magnetic stirring continued.
Frequency of preparation: Weekly.
Storage of formulation: Refrigerated (2 to 8°C) and protected from light.
Test item accounting: Detailed records of compound usage were maintained. The amount of test item necessary to prepare the formulations and the amount actually used were determined on each occasion. The difference between these amounts was checked before the formulations were dispensed.
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Stability and homogeneity: The formulations prepared at 1 and 200 mg/mL were found to be homogeneous and stable at ambient temperature (15 to 25ºC) for one day and refrigerated (2 to 8°C) storage for 15 days.
Achieved concentration: Samples of each of the first and last formulations prepared for administration for all groups were analyzed for achieved concentration of the test item.
Details on mating procedure:
Male/female ratio: 1:1 with identified stock males.
Daily checks for evidence of mating: Ejected copulation plugs in cage tray and vaginal smears were checked for the presence of sperm.
Day 0 of gestation: When positive evidence of mating was detected.
A colony of stud males was maintained specifically for the purpose of mating; these animals were not part of the study and were maintained as stock animals.
Duration of treatment / exposure:
From Day 6 to 19 after mating

Frequency of treatment:
Once daily
Doses / concentrationsopen allclose all
Dose / conc.:
0 mg/kg bw/day (nominal)
Dose / conc.:
125 mg/kg bw/day (nominal)
Dose / conc.:
175 mg/kg bw/day (nominal)
Dose / conc.:
250 mg/kg bw/day (nominal)
No. of animals per sex per dose:
20 animals/dose
Control animals:
yes, concurrent vehicle
Details on study design:
- Dose selection rationale: The dose levels selected for investigation in this study of embryo-fetal development were selected in conjunction with the Sponsor and based on the results of a preliminary toxicity study in which three groups of five male and five female Crl:CD(SD) rats received 100, 300 or 1000 mg/kg/day for up to two weeks.
- Fasting period before blood sampling for (rat) dam thyroid hormones: No

Examinations

Maternal examinations:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice a day

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Days 0, 5, 12, 18 and 20 after mating

BODY WEIGHT: Yes
- Time schedule for examinations: Days 0, 3 and 6-20 after mating

FOOD CONSUMPTION: Yes
- Food consumption for each animal: Days 0-3, 3-6, 6-10, 10-14, 14-18 and 18-20 after mating inclusive

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 20
- Organs examined: Thyroid with parathyroids

OTHER:
- Thyroid Hormone Analysis
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
Blood sampling:
- Plasma: No
- Serum: Yes
- Volume collected: 1.0 mL
Fetal examinations:
- External examinations: Yes: [all per litter]
- Soft tissue examinations: Yes: [half per litter ]
- Skeletal examinations: Yes: [half per litter]
- Head examinations: No
- Anogenital distance of all live rodent pups: Yes
Statistics:
For adult parameters, the analyses were carried out using the individual animal as the basic experimental unit. For litter/fetal findings the litter was taken as the treated unit and the basis for statistical analysis and biological significance was assessed with relevance to the severity of the anomaly and the incidence of the finding within the background control population.
Historical control data:
Historical Control data were supplied for selected observations where this information was considered to assist interpretation of study data, and include both fetal and litter incidences.

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:
no effects observed
Description (incidence and severity):
There were no treatment-related clinical signs. Post-dose observations were limited to transient incidences of salivation on occasion at 250 or 125 mg/kg/day and piloerection and chin rubbing on occasion at 250 mg/kg/day.
Mortality:
mortality observed, non-treatment-related
Description (incidence):
At 250 mg/kg/day there were three unscheduled deaths (during the main phase of the study). Female 3F 67 that received 250 mg/kg/day died during dosing and was dispatched to necropsy on Day 8 of gestation; macroscopic examination revealed a perforated esophagus and clotted blood in the thoracic cavity. Female 3F 63 that received 250 mg/kg/day was found dead on Day 17 of gestation; macroscopic examination revealed a perforated esophagus and clear fluid in the thoracic cavity, with multiple pale adhesions. Female 2F 57 that received 125 mg/kg/day was also dispatched to necropsy for welfare reasons on Day 18 of gestation due to signs of decreased activity and labored breathing; macroscopic examination revealed a perforated esophagus and pale fluid in the thoracic cavity. These deaths were as a result of mal-dosing and were not considered treatment-related.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
An initial slight group mean body weight loss was observed following the commencement of treatment, between Days 6-7 at 250 mg/kg/day, with group mean body weight stasis observed for the other groups, including Control. Thereafter, group mean body weight gain was observed in all groups, however, an overall dose-related decrease in group mean body weight gain was observed from Day 6 to 20 of gestation with statistical significance attained in all treated groups (42%, 22% and 12% lower at 250, 175 or 125 mg/kg/day respectively). Consequently, group mean terminal body weights and mean terminal body weights adjusted for the contribution of the gravid uterine weight were statistically significantly lower than Control in females that received 250 or 175 mg/kg/day.
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Description (incidence and severity):
Following the commencement of treatment on Day 6 of gestation, a dose-related reduction in food intake was observed in all groups of treated females, when compared to Control, with an average mean food intake of 15 g/animal/day consumed throughout the treatment period at 250 mg/kg/day (29% lower than Control), 16 g/animal/day at 175 mg/kg/day (24% lower than Control) and 19 g/animal/day at 125 mg/kg/day (10% lower than Control). There was no conclusive improvement in food consumption at any dose level investigated.
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
Endocrine 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
Description (incidence and severity):
No treatment-related variation in thyroid/parathyroid weights occurred. All differences were consistent with normal variation and considered incidental.
Gross pathological findings:
no effects observed
Description (incidence and severity):
There were no treatment-related macroscopic findings at scheduled termination of Day 20 of gestation.
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
no effects observed
Description (incidence and severity):
No test article-related microscopic findings were observed in the thyroid or parathyroid of the treated females.
Histopathological findings: neoplastic:
no effects observed
Other effects:
effects observed, treatment-related
Description (incidence and severity):
Mean gravid uterine weights were slightly low at 250 mg/kg/day (9% lower) and an overall statistically significant group mean maternal body weight loss (-15 g) was observed between Days 6 to 20 of gestation when adjusted for gravid uterine weight. A review of the individual data revealed marked adjusted maternal body weight losses for 2 females at 250 mg/kg/day (-76 g and -63 g for females 3F 59 and 3F 64, respectively). When adjusted for the contribution of the gravid uterine weight, group mean maternal body weight stasis was observed between Day 6 to 20 of gestation at 175 mg/kg/day, however, a review of the individual data revealed body weight losses in nearly half of the females. A slight mean adjusted body weight gain was observed at 125 mg/kg/day, although lower than Control.

Maternal developmental toxicity

Number of abortions:
no effects observed
Pre- and post-implantation loss:
effects observed, non-treatment-related
Description (incidence and severity):
It was noted that pre-implantation loss was slightly higher than Control at 250 mg/kg/day, however, statistical significance was not attained and since pre-implantation loss was not affected by treatment at 500 mg/kg/day (during the preliminary phase) and live litter size was similar to Controls, this change was considered incidental.
Total litter losses by resorption:
no effects observed
Early or late resorptions:
no effects observed
Changes in pregnancy duration:
no effects observed
Changes in number of pregnant:
no effects observed
Details on maternal toxic effects:
Litter data, as assessed by the mean numbers of corpora lutea, implantations, resorptions, and the extent of pre- or post-implantation loss were not adversely effected by maternal treatment.

Effect levels (maternal animals)

Key result
Dose descriptor:
NOAEL
Effect level:
125 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
body weight and weight gain

Maternal abnormalities

Key result
Abnormalities:
no effects observed

Results (fetuses)

Fetal body weight changes:
effects observed, treatment-related
Description (incidence and severity):
Male, female and overall fetal weights as well as total litter weight were slightly lower than Control at 250 mg/kg/day with statistical significance attained for the female fetal weights, however, this value was within the HCD range.
Reduction in number of live offspring:
no effects observed
Changes in sex ratio:
no effects observed
Changes in litter size and weights:
no effects observed
Anogenital distance of all rodent fetuses:
no effects observed
Changes in postnatal survival:
not examined
External malformations:
no effects observed
Skeletal malformations:
no effects observed
Visceral malformations:
no effects observed
Details on embryotoxic / teratogenic effects:
Litter data, as assessed by the mean numbers of live young and sex ratio were not adversely effected by maternal treatment.

There were no fetal findings observed at macroscopic examination that were considered to be related to the test item. The incidence of major and minor abnormalities and skeletal variants showed no relationship to treatment.
It was noted that at 175 mg/kg/day there was a slight increase in abdominal cavity haemorrhages compared to concurrent control but values were within the Historical Control Data (HCD) range.

Effect levels (fetuses)

Key result
Dose descriptor:
NOAEL
Effect level:
250 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
reduction in number of live offspring
changes in sex ratio
fetal/pup body weight changes
changes in litter size and weights
changes in postnatal survival
external malformations
skeletal malformations
visceral malformations

Fetal abnormalities

Key result
Abnormalities:
no effects observed

Overall developmental toxicity

Key result
Developmental effects observed:
no

Applicant's summary and conclusion

Conclusions:
Based on the results of this study, the No-Observed-Adverse-Effect-Level (NOAEL) for maternal toxicity was concluded to be 125 mg/kg/day and the NOAEL for embryo-fetal survival and development was concluded to be 250 mg/kg/day.
Executive summary:

The purpose of this study was to assess the influence of Amines, tallow alkyl, dodecylbenzene sulfonate, an industrial chemical, on embryo-fetal survival and development when administered during the organogenesis and fetal growth phases of pregnancy in the Crl:CD(SD) rat.
For the preliminary phase of the study, three groups of six females received Amines, tallow alkyl, dodecylbenzene sulfonate at doses of 125, 250 or 500 mg/kg/day by oral gavage administration at a dose volume of 5 mL/kg, from Day 6 to 19 after mating. For the main phase of the study, two groups of 14 females received Amines, tallow alkyl, dodecylbenzene sulfonate at doses of 125 or 250 mg/kg/day and a group of 20 females received Amines, tallow alkyl, dodecylbenzene sulfonate at a dose of 175 mg/kg/day by oral gavage administration at a dose volume of 5 mL/kg, from Day 6 to 19 after mating. Control groups comprising six females (preliminary phase) or 14 females (main phase) received the vehicle, Corn oil, at the same volume dose as the treated groups. For both phases, animals were killed on Day 20 after mating for reproductive assessment and fetal examination.
Clinical observations, body weight and food consumption were recorded. Adult females were examined macroscopically at necropsy on Day 20 after mating, blood samples were taken for thyroid hormone analysis and the gravid uterine weight and thyroid weight were recorded. Microscopic pathology investigations were also undertaken. Ano-genital distance and individual body weight was measured for fetuses and all fetuses were examined macroscopically at necropsy and subsequently by detailed internal visceral examination or skeletal examination.


For the first dose preparation, the mean concentrations for Group 3 (250 mg/kg/day) and Group 4 (500 mg/kg/day) were within 4% of the nominal concentration, confirming the accuracy of formulation. The difference from mean remained within 3%, confirming precise analysis. Following rework and contingency analysis, the mean concentration for Group 2 (125 mg/kg/day) was confirmed to be outside of the acceptance criteria at +15.6% of the nominal concentration resulting in an actual dose level of 144.5 mg/kg/day for this period of the study. The coefficient of variation for the two original samples and two contingency samples was 5.66%. The samples from the last preparation were not analyzed in error (see Section 4).
Treatment at 500 mg/kg/day during the preliminary phase resulted in a decrease in mean T3 and T4 concentrations, one premature death of uncertain relationship to treatment and transient incidences of chin rubbing, piloerection and salivation post-dose. In addition, a 92% decrease in mean maternal body weight gain was observed, compared to Control. A marked mean maternal body weight loss (-56 g) was apparent when adjusted for gravid uterus weight and a 52% decrease in food intake was also observed. Furthermore, although all females were found to be pregnant, post-implantation loss was slightly increased such that the number of live young was slightly low. Placental and fetal weights (male, female and total) were reduced and these effects in conjunction with the lower numbers of live young resulted in low litter weights. A dose level of 500 mg/kg/day was considered unsuitable for further investigation during the subsequent main phase of the study, primarily due to the extent of maternal body weight loss, the reduction in food intake and the uncertain relationship to treatment of the premature death.
Treatment at 250, 175 or 125 mg/kg/day was tolerated. There were no treatment-related premature deaths. A dose dependent decrease in mean T3 and T4 concentrations was observed in all groups of treated females, however, there was no effect on TSH concentrations at any dose level, there were no associated thyroid/parathyroid weight changes and no macroscopic or microscopic changes detected in the thyroids at any dose level investigated. Post-dose observations were limited to transient incidences of salivation on occasion at 250 or 175 mg/kg/day and piloerection and chin rubbing on occasion at 250 mg/kg/day.
An initial slight group mean body weight loss was observed between Days 6-7 of gestation at 250 mg/kg/day, with group mean body weight stasis observed for the other groups, including Control. Thereafter, group mean body weight gain was observed in all groups, however, an overall dose-related decrease in group mean body weight gain was observed from Day 6 to 20 of gestation (42%, 22% and 12% lower at 250, 175 or 125 mg/kg/day respectively). Consequently, group mean terminal body weights and mean terminal body weights adjusted for the contribution of the gravid uterine weight were statistically significantly lower than Control in females that received 250 or 175 mg/kg/day. Mean gravid uterine weights were slightly low at 250 mg/kg/day (9% lower) and an overall group mean maternal body weight loss (-15 g) was observed between Days 6 to 20 of gestation when adjusted for gravid uterine weight. A review of the individual data revealed marked adjusted maternal body weight losses for 2 females at 250 mg/kg/day (-76 g and -63 g for females 3F 59 and 3F 64, respectively). When adjusted for the contribution of the gravid uterine weight, group mean maternal body weight stasis was observed between Day 6 to 20 of gestation at 175 mg/kg/day, however, a review of the individual data revealed slight body weight losses in nearly half of the females. A slight mean adjusted body weight gain was observed at 125 mg/kg/day, although lower than Control.
Following the commencement of treatment on Day 6 of gestation, a dose-related reduction in food intake was observed in all groups of treated females, when compared to Control, with an average mean food intake of 15 g/animal/day consumed throughout the treatment period at 250 mg/kg/day (29% lower than Control), 16 g/animal/day at 175 mg/kg/day (24% lower than Control) and 19 g/animal/day at 125 mg/kg/day (10% lower than Control).
There were no treatment-related changes in thyroid/parathyroid weights and no treatment-related macroscopic findings at scheduled termination. No treatment-related microscopic findings were observed in the thyroid or parathyroid at any dose level investigated.
Male, female and overall fetal weights as well as total litter weight were slightly lower than Control at 250 mg/kg/day with statistical significance attained for the female fetal weights. There was no effect of maternal treatment on mean numbers of corpora lutea, implantations, resorptions, live young, the extent of pre- or post-implantation loss, sex ratio or ano-genital distance and there were no major or minor fetal abnormalities or skeletal variants considered related to treatment at any dose level investigated.

Categories Display