Registration Dossier

Toxicological information

Developmental toxicity / teratogenicity

Currently viewing:

Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Study period:
16 April 2020 -
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2020
Report Date:
2020

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 414 (Prenatal Developmental Toxicity Study)
Version / remarks:
(adopted 25 June 2018)
Deviations:
yes
Remarks:
1 animal in Gp 3 (GD 11) was marked as administered 0.00 mL. Thyroid hormone samples were stored incorrectly at -80°C for less than 24 hours. These study deviations neither affected overall interpretation nor compromised the integrity of study findings.
GLP compliance:
yes (incl. certificate)
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Benzenesulfonic acid, C10-13-alkyl derivs., compds. with triethanolamine
Specific details on test material used for the study:
Appearance: Yellow / brown liquid
Purity: 51.8% Active Substance
Correction factor: 1.93
Storage conditions: Sealed container, 15 to 25°C, protected from light.
Lot number: 200032320

Test animals

Species:
rat
Strain:
other: Crl:WI(Han)
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Margate, United Kingdom
- Age at study initiation: 9 to 10 weeks old
- Weight at study initiation: 140 g
- Fasting period before study: No
- Housing: Animals were housed in cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: Acclimation was limited by mated status

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25°C
- Humidity (%): 40 to 70%
- Air changes (per hr): 15 air changes/hour
- Photoperiod (hrs dark / hrs light): Fluorescent lighting was controlled automatically to give a cycle of 12 hours of light and 12 hours of dark.

IN-LIFE DATES: From: To: 20 April 2020 - 11 May 2020

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
water
Remarks:
Purified
Analytical verification of doses or concentrations:
yes
Details on mating procedure:
Mating (overnight at the supplier’s laboratory) was confirmed by the presence of a vaginal plug in situ, or other evidence of mating, if necessary. The day on which mating was confirmed was designated as Gestation Day (GD) 0.
Duration of treatment / exposure:
From Gestation Day (GD) 6 through 20
Frequency of treatment:
Daily
Duration of test:
GD 6 to 20
Doses / concentrationsopen allclose all
Dose / conc.:
0 mg/kg bw/day (actual dose received)
Remarks:
Control (Purified water)
Dose / conc.:
100 mg/kg bw/day (actual dose received)
Dose / conc.:
300 mg/kg bw/day (actual dose received)
Dose / conc.:
500 mg/kg bw/day (actual dose received)
No. of animals per sex per dose:
20 females per dose
Control animals:
yes, concurrent vehicle

Examinations

Maternal examinations:
Assessment of toxicity was based on mortality, clinical and postdose observations, body weights, food consumption, and clinical and anatomic pathology of the thyroid. Necropsies were performed on all animals on GD 21 and all macroscopic abnormalities and thyroid weights were recorded for the maternal animals. Microscopic examinations of the thyroid gland were also performed. The progress and outcome of pregnancy were also evaluated.
Ovaries and uterine content:
Pregnancy status
Gravid uterus weight
Terminal body weight (recorded for adjusted gravid uterus weight calculations only and have not been reported)
Number of corpora lutea
Number and intrauterine position of implantations subdivided into:
Live fetuses
Early intrauterine deaths
Late intrauterine deaths
Dead fetuses
Fetal examinations:
Individual fetal and placental weights were recorded; fetuses were examined externally and sexed, and anogenital distance was recorded.
Fetal abnormalities were classified as malformations (rare and/or potentially lethal defects) or variations (commonly occurring non-lethal abnormalities).
Statistics:
Data for each fetal sex were analyzed separately; only data collected on or after the first day of dosing were analyzed statistically.
Data from non-pregnant animals were excluded from statistical analysis.
The pairwise comparisons of interest were: Groups 2, 3, and 4 versus Group 1.
Analysis of variance (ANOVA) and pairwise comparisons, as applicable, were used to analyze the following.
• Body weight
• Body weight change
• Food consumption
Prior to performing the ANOVA, Levene’s test was performed to test for equality of variances between groups:

All statistical tests were evaluated at the 5.0, 1.0, and 0.1% probability levels.
Historical control data:
Historical control data included were generated outside the scope of this study; therefore, no claim of compliance will be made for these data. Data were generated from studies performed within the GLP laboratory, by GLP trained staff, whether a claim of GLP compliance was made or not, and were included in the compilation of historical control ranges without bias.

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:
no effects observed
Description (incidence and severity):
Postdose observations during return to home cage consisted of mouth rubbing and excessive salivation and were observed in all test article-treated groups, with the incidence increasing with dose levels. Mouth rubbing was observed 1 hour postdose for one animal administered 500 mg/kg/day AI (Animal R0313). These observations were considered attributable to the unpalatable nature of the test article formulations and did not represent systemic toxicity; as such, these observations were considered nonadverse.
Dermal irritation (if dermal study):
not examined
Mortality:
no mortality observed
Description (incidence):
One female administered 500 mg/kg/day AI (Animal R0312) was sacrificed on GD 11. No clinical observations were noted for this animal until GD 11, when decreased activity, excessive salivation, piloerection, audible respiration, and a thin appearance were recorded. Due to the severity of these observations, this animal was subsequently terminated. The animal was confirmed as pregnant at necropsy, and was recorded as thin with a thick caudal region of the esophagus. Although the etiology of this finding was unclear, in isolation, this was considered not substance related.
Body weight and weight changes:
no effects observed
Description (incidence and severity):
The statistically significant intergroup differences detected were considered to have arisen incidentally and were not associated with the test article.
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Description (incidence and severity):
Test article-related reductions in mean food consumption were observed following the start of administration of 500 mg/kg/day AI compared with controls (GD 6 through 8; P < 0.001). Improvement was observed thereafter, and as such, these initial reductions were considered not to represent an adverse effect of the test article.
No test article-related effect on food consumption was observed following 100 or 300 mg/kg/day AI.
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:
no effects observed
Description (incidence and severity):
No substance-related changes in total thyroxine (T4), thyroid stimulating hormone (TSH) or total thyroid triiodothyronine (T3) were observed.
Urinalysis findings:
not examined
Behaviour (functional findings):
effects observed, treatment-related
Description (incidence and severity):
Paddling behavior was noted for four animals administered 500 mg/kg/day AI (and one female administered 300 mg/kg/day AI (Animal R0204) during return to home cage. These observations were considered attributable to the unpalatable nature of the test article formulations and did not represent systemic toxicity; as such, these observations were considered nonadverse.
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
no effects observed
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
not examined

Maternal developmental toxicity

Number of abortions:
no effects observed
Description (incidence and severity):
Of the 20 females in each group, 18, 19, 18, or 19 females administered 0, 100, 300 or 500 mg/kg/day AI, respectively, were pregnant with live fetuses at the scheduled sacrifice.
Pre- and post-implantation loss:
no effects observed
Total litter losses by resorption:
effects observed, non-treatment-related
Description (incidence and severity):
One female administered 300 mg/kg/day AI (Animal R0216) had a total in utero litter loss. This was an isolated finding, and in the absence of a dose relationship, was considered to have arisen incidentally.
Early or late resorptions:
no effects observed
Dead fetuses:
no effects observed
Changes in pregnancy duration:
no effects observed
Changes in number of pregnant:
no effects observed

Effect levels (maternal animals)

Key result
Dose descriptor:
NOAEL
Effect level:
>= 500 mg/kg bw/day (actual dose received)
Based on:
act. ingr.
Basis for effect level:
clinical signs
mortality
body weight and weight gain
food consumption and compound intake
clinical biochemistry
organ weights and organ / body weight ratios
gross pathology
histopathology: non-neoplastic

Maternal abnormalities

Key result
Abnormalities:
no effects observed

Results (fetuses)

Fetal body weight changes:
not examined
Reduction in number of live offspring:
not examined
Changes in sex ratio:
no effects observed
Changes in litter size and weights:
no effects observed
External malformations:
no effects observed
Skeletal malformations:
effects observed, non-treatment-related
Description (incidence and severity):
Fetal variations of higher incidences of unossified metatarsals and cervical centrum were observed for litters from animals administered 500 mg/kg/day AI, compared with controls. Higher incidences of unossified cervical centrum were also observed for litters from females administered 300 mg/kg/day AI, compared with controls. There was no overarching pattern of effect observed, and the ossification deficits noted do not impact viability and are most likely transient; therefore, the increased incidence of these variations were considered not to represent an adverse effect of the substance.
Visceral malformations:
no effects observed

Effect levels (fetuses)

Key result
Dose descriptor:
NOAEL
Effect level:
>= 500 mg/kg bw/day (actual dose received)
Based on:
act. ingr.
Sex:
male/female
Basis for effect level:
reduction in number of live offspring
changes in sex ratio
changes in litter size and weights
external malformations
skeletal malformations
visceral malformations

Fetal abnormalities

Key result
Abnormalities:
no effects observed

Overall developmental toxicity

Key result
Developmental effects observed:
no
Lowest effective dose / conc.:
500 mg/kg bw/day (actual dose received)
Treatment related:
no

Any other information on results incl. tables

 Variation  Dose Level (AI):  0 (Control)  100 mg/kg/day  300 mg/kg/day 500 mg/kg/day   Historical control data

cervical centrum

unossified

 

% Litter

 44 53  72  78*  0 to 95%
    

% Fetal

 14.72 16.05   21.85  33.53  

hindlimb

metatarsal unossified

% Litter

 0  0 17   0 to 26%
    

% Fetal

 0  1.05  0.00  4.23  

Applicant's summary and conclusion

Conclusions:
The no observed adverse effect level (NOAEL) for the maternal animal and subsequent offspring is 500 mg/kg/day AI, based no adverse effects occurring in maternal animals or foetuses.
Executive summary:

Once-daily oral gavage administration of 0 (control article [vehicle]), 100, 300, or 500 mg/kg/day AI of Benzenesulfonic acid. 4-C10-sec-alkyl derivs., compds. with triethanolamine from GD 6 through 20 resulted in substance-related postdose observations of mouth rubbing and paddling behavior. Initial reductions in food consumption were observed for females administered 500 mg/kg/day AI, and foetal variations of increased incidences of unossified metatarsal and cervical centrum for litters from animals administered 300 or 500 mg/kg/day AI, compared with controls. These findings did not result in a detrimental effect on the maternal animal or the subsequent litter; as such, the no observed adverse effect level (NOAEL) for the maternal animal and subsequent offspring is 500 mg/kg/day AI.