Benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs., para-, sodium salts

Repeated dose toxicity: oral

Administrative data

Endpoint:

repeated dose toxicity: oral

Remarks:

other: one generation reproduction toxicity study

Type of information:

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

Adequacy of study:

key study

Study period:

2003-2004

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted to OECD guidelines to to GLP, and therefore meets the requirements for Klimisch code 1. However as this study is used in the context of a read across, Klimisch 2 is assigned.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD 415

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Benzenesulfonic acid, C14-24-branched and linear alkyl derivs., calcium salts

IUPAC Name:

Benzenesulfonic acid, C14-24-branched and linear alkyl derivs., calcium salts

Details on test material:

The test article (CAS 115733-09-0) is from the chemical group of alkaryl sulfonates.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS: Sprague-Dawley Crl: CD®(SD) IGS BR rats,
- Source: Charles River Laboratories
- Age at study initiation: (P) males 5 wks, females 7 weeks
Males approximately 7 weeks of age at initiation of treatment. Females approximately 8 weeks of age at initiation of treatment.
- Weight at study initiation: (P) Males: 154-197 g; Females: 139-184 g
- Housing: Suspended wire cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-26°C
- Humidity (%): 30-70%
- Air changes (per hr): 10-15 changes/hour
- Photoperiod (hrs dark / hrs light): 12 hours light/dark cycle

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS: Corn oil was added to the test substance to achieve the desired volume and then stirred for 30 minutes.
VEHICLE: Justification for use and choice of vehicle (if other than water): Corn oil
The test article was administered orally via gastric intubation

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Analytical confirmation of concentration: Homogeneity, stability and weekly dose concentration confirmation.

Duration of treatment / exposure:

F0 males - 70 days premating; mating period through completion of parturition
F0 females - 14 days premating; mating; 25 days of gestation and 20 days of lactation.

Frequency of treatment:

once daily

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
0 mg/kg bw
Basis:
actual ingested

Doses / concentrations 2

Remarks:

Doses / Concentrations:
50 mg/kg bw
Basis:
actual ingested

Doses / concentrations 3

Remarks:

Doses / Concentrations:
167 mg/kg bw
Basis:
actual ingested

Doses / concentrations 4

Remarks:

Doses / Concentrations:
500 mg/kg bw
Basis:
actual ingested

No. of animals per sex per dose:

28 F0 rats/sex/group in control, low, mid and high dose

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Based on results of a 28 day oral gavage study (according to OECD 407).
- Control and treatment groups: 28 F0 rats/sex/group in the control, low, mid and high dose groups.
- Mating: 1 male mated to 1 female from the same group until evidence of mating (presence of copulatory plug or sperm) was observed. If evidence of mating was not observed mating was discontinued after three weeks.

Examinations

Observations and examinations performed and frequency:

Parental animals:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Weekly and daily for females during gestation

BODY WEIGHT: Yes
- Time schedule for examinations: Weekly and on the day on euthanasia for males. After evidence of mating, females were weighed on gestational days 0, 7, 14 and 21 and on lactation days 1, 4, 7, 14 and 21.

Sperm parameters (Parental animals)
Parameters examined in P male parental generations:
testis weight, epididymis weight, sperm count in epididymides, enumeration of cauda epididymal sperm reserve, sperm motility, sperm morphology.

Sacrifice and pathology:

gross necropsy on death, organ weights and microscopic examination on termination
SACRIFICE
- Male animals: All surviving animals after completion of female parturition.
- Maternal animals: All surviving animals that delivered on lactation day 21; females that failed to deliver were sacrificed on gestation day 25.

GROSS NECROPSY
- Gross necropsy consisted of external and internal examinations including the cervical, thoracic, and abdominal viscera.

Statistics:

ANOVA for body weights, changes, food consumption semen parameters, organ weights.

Body weights, body weight changes, food consumption, semen parameters, organ weights, number of days to mating, gestation length, pup viability data, total pups delivered, pup body weights and mean live litter size were analysed by ANOVA followed, as needed, by Dunnett’s test. Count data were analysed by Chi-Square test followed by Fisher’s Exact Test for copulation and fertility indices, pup sex ratios, number of live and dead pups/group and pup survival. All analysis were two-tailed with a minimum significance level of 5%..

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not specified

Water consumption and compound intake (if drinking water study):

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Details on results:

There were no remarkable findings in F0 males, with the exception of post dosing salivation.
In F0 females there were no remarkable findings with the exception of negative ammonium sulphide staining in two high dose and one mid dose animal.

Effect levels

Dose descriptor:

NOAEL

Effect level:

> 500 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No significant adverse effects occurred at 500 mg/kg bw (highest dose tested).

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

Results of the homogeneity analysis indicate that the test article was homogeneous in the vehicle and stable for ten days when stored under ambient conditions. Concentration analysis confirmed that the test article was at the appropriate concentration in the dosing solutions.

Results

F0 males exhibited a dose related increase in post dosing salivation and dark material around the nose in the mid and high dose groups. The remaining F0 male parameters were unremarkable including: mean body weight and food consumption, mating and fertility indicies, absolute and relative organ weights, sperm evaluation parameters and macro and microscopic pathology.

The clinical signs of the Fo females were generally unremarkable. There were no toxicologically meaningful differences between the control low, mid and high dose groups with respect to F0 female mean body weights, body weight change, food consumption, mating and fertility indicies, precoital intervals or gestation length. A macroscopic finding observed in two high dose and one mid female sacrificed on post mating day 25 was a finding of negative ammonium sulfide staining in animals that failed to deliver and were euthanized on gestation day 25.

No other remarkable findings were noted in the F0 females at necropsy and no meaningful microscopic lesions were observed in any of the treated F0 females.

Applicant's summary and conclusion

Conclusions:

Adverse effects did not occur in parental animals at doses up to 500 mg/kg bw/day, therefore a NOAEL of >500 mg/kg bw was identified with the help of this study.

Executive summary:

In a key 1-generation reproduction study, the calcium sulfonate read across substance (CAS 115733-09-0) was administered in corn oil via oral gavage to 28 Sprague-Dawley rats/sex at dose levels of 0, 50, 167 and 500 mg/kg bw/day (Bjorn, 2004, according to OECD 415). All F0 males were dosed for 70 days prior to mating, mating (maximum 3 weeks) and through the completion of parturition. All F0 females were dosed for up to 70 days (14 days prior to mating, during mating and gestation, and through day 20 of lactation). The animals were observed twice daily for appearance and behaviour, and a detailed clinical observation was performed weekly and daily for females during gestation. Cage site observations were performed daily approximately 30 to 120 minutes post dosing. In addition, the bodyweights were determined weekly and on the day of euthanasia for males. Females were weighed after evidence of mating on gestational days 0, 7, 14 and 21 and on lactation days 1, 4, 7, 14 and 21. Food consumption was recorded on the same days as body weights except during the mating period and during lactation. Animals were paired 1:1 for mating, after successful mating each pregnant female was caged individually. Positive evidence of mating was confirmed by the presence of sperm or a vaginal copulatory plug (day 0 of gestation). If evidence of mating was not present after three weeks, mating was discontinued. All of the surviving F0 females were allowed to deliver and rear their pups to lactation day 21.

Gross necropsies (consisting of external and internal examinations including the cervical, thoracic and abdominal viscera) were performed on death, organ weights and microscopic examinations were performed on termination. The surviving F0 dams were necropsied on lactation day 21, following a minimum of 60 days of dosing. The surviving F0 males were necropsied at the conclusion of parturition following a minimum of 96 days of dosing. F0 females that failed to deliver were necropsied on post-mating day 25 (with evidence of mating) or 25 days following the termination of the mating period (with no evidence of mating). Organ weights were determined and microscopic examinations were conducted for all surviving control and high dose F0 animals. Tissues examined microscopically included the liver, kidney, brain, right epididymides, cervix, coagulation gland, ovaries, pituitary, prostrate, seminal vesicles, testes, uterus, vagina and gross lesions. F0 animals from all groups found dead or sacrificed early were subjected to a gross necropsy and the microscopic evaluation of all tissues. Sperm was collected from all surviving F0 males and evaluated for sperm count, concentration, motility and morphology assessment. The parameters examined in P males included: testis weight, epididymis weight, sperm count in epididymides, enumeration of cauda epididymal sperm reserve, sperm motility and sperm morphology.

No substance related effects occurred in treated animals, except for the observation of post dosing salivation and dark material around the nose in the mid and high dose groups in F0 males and the negative ammonium sulfide staining in two high dose and one mid dose F0-female. As no effects occurred at the highest dose, a NOAEL of > 500 mg/kg bw was identified.