Sodium 2-[(2-aminoethyl)amino]ethanesulphonate

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Sodium 2-[(2-aminoethyl)amino]ethanesulphonate

EC Number:

252-173-9

EC Name:

Sodium 2-[(2-aminoethyl)amino]ethanesulphonate

Cas Number:

34730-59-1

Molecular formula:

C4H12N2O3S.Na

IUPAC Name:

sodium 2-(2-aminoethylamino)ethanesulfonate

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

The administration volume was 10 ml/kg body weight per day.

Analytical verification of doses or concentrations:

no

Details on analytical verification of doses or concentrations:

The test item AAS-Loesung is a 48.8% solution in water. Dilution in water is therefore expected not to influence the stability of the test item. The stability of the formulations was declared by the sponsor as at least 8 days.

Duration of treatment / exposure:

29 days

Frequency of treatment:

once daily

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
100, 300, 1000 mg/kg bw
Basis:
other: solid content of AAS-Loesung (48.8%)

Doses / concentrations 2

Remarks:

Doses / Concentrations:
205, 615, 2050 mg/kg bw
Basis:
other: AAS-Loesung

No. of animals per sex per dose:

five

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:

In a two-week pilot study three animals per sex and dose received daily doses of 0, 100, 500, or 1000 mg/kg, calculated on the solid content of the test item. In-life data, necropsy, and body weith development was not influenced by the treatment. Water intake was increased in all dosing groups compared to controls. However, difference to control was more pronouned in week 1 than in week 2 and there was no clear dose depencence.

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: daily

BODY WEIGHT: Yes
- Time schedule for examinations: daily

FOOD CONSUMPTION: Yes
- Time schedule for examinations: weekly

WATER CONSUMPTION: Yes
- Time schedule for examinations: weekly

HAEMATOLOGY: Yes
- Time schedule for collection of blood: once, day 28
- How many animals: all dose groups incl. controls

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: once, day 28
- How many animals: all dose groups incl. controls

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: FOB (functional observation battery): once, week 4; MA (motor activity): once, week 4
- Dose groups that were examined: all dose groups incl. controls
- Battery of functions tested: Functional Observational Battery (FOB); Motor Activity (MA)

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (all dose groups and controls)

ORGAN Weights:
Brain, heart, liver, spleen, kidneys (both), thymus, adrenal glands (both), epididymides (both), testes (both), prostate, seminal vesicles with coagulation glands, ovaries/oviducts (both) and uterus/cervix.

Fixed organs:
Adrenals, aorta, brain (cerebrum, cerebellum, ponslmedulla), epididymides, esophagus, eyes, eyelids, extraorbital lachrymal glands, femur, harderian glands, head (with nasal and paranasal cavities), heart, intestine (duodenum, jejunum, ileum, cecum, colon, rectum and remaining intestine), kidneys, larynx, liver, lymph nodes (mandibular, bronchial/hilus, and mesenteric), lung, mamma, optical nerves, ovaries, oviducts, pancreas, pharynx, pituitary, prostate, salivary glands, sciatic nerve, seminal vesicles (incl. coagulating glands), skeletal muscle (thigh), skin (mammary and muzzle), spinal cord (cervical, thoracic, lumbar), spleen, sternum, stomach (forestomach and glandular stomach), testes, thymus, thyroids (including parathyroid glands), tongue, trachea, ureter, urethra, urinary bladder, uterus with uterine cervix, vagina, Zymbal’s glands and all organs or tissues with macroscopic findings.

HISTOPATHOLOGY: Yes (high dose group and controls)
- Microscopic: Adrenals, aorta, brain (cerebrum, cerebellum, brain stem), epididymides, eyes, femur, heart, intestine (duodenum, jejunum, ileum, cecum, colon, rectum and remaining intestine), kidneys, lung, ovaries, oviducts, prostate, sciatic nerve, skeletal muscle (thigh), spinal cord (cervical, thoracic, lumbar), sternum with bone marrow, testes, seminal vesicles (incl. coagulating glands), stomach, trachea and thyroids glands, urinary bladder, uterus with uterine cervix, vagina and all organs or tissues with macroscopic findings.

HISTOPATHOLOGY: Yes (all dose groups and controls)
-Microscopic: thyroids

Statistics:

Statistical tests on FOB, body weights and weight gain as well as on absolute organ weights were done using the Dunnett Exact Homogeneous Test. For relative organ weights the Dunnett Exact Homogeneous Test after logarithmic transformation was used.
Data for food and water intake were statistically evaluated using the adjusted Mann-Whitney U-test.
The Dunnett Exact Homogeneous or Heterogeneous Test, the Dunnett Exact Homogeneous Test after logarithmic transformation or the Bonferroni/Mann-Whitney U-test were used for clinical pathology parameters. Descriptive statistics were provided per sex, dose group and time point for all parameters that were recorded with a specified unit. This included measures of general tendency (mean and median (median not given for food and water intake)) and general variability (standard deviation, minimum and maximum) as appropriate.
For statistical evaluations ofhistopathological data, if any, the PATHDATA program were used and described in detail in the Pathology Report. Statistics ofMA/LMA were generated with an evaluation step ofthe SPADER application. Generation of results was done for duration and interval analysis separately. A preliminary step determined whether there exist significant interactions at all for duration and interval analysis. If so, a Dunnett test based on the GLM Procedure were executed to determine which specific groups differ in a significant way on basis of the computed means with regard to the comparison group.

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 examined

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

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Description (incidence and severity):

slight organ weight changes in some animals were without histopathological correlated and therefore regarded as of no toxicological relevance

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Details on results:

ORGAN WEIGHTS:
At necropsy, two males treated with 1000 mglkg showed an enlarged spleen. Both absolute and relative weight of spleen and epididymitis were increased in this group. The increase in the mean weight is the consequence of the high spleen weight of rat No. 16. As no histopathological correlate was obvious these changes were not regarded to be of toxicological relevance.
Determination of organ weights showed that absolute and relative weight of livers was increased at 1 000 mg/kg in males. Furthermore, absolute weights of kidneys were increased starting at 300 mg/kg and relative weights at 1000 mg/kg in males. As the differences to control were relatively slight and no histopathological correlates were observed, this is not regarded to be of toxicological relevance.
The increase in both mean absolute and relative weight of epididymitis was 1 000 mg/kg was due to the high weight of epididymitis of male No. 16. Histopathological evaluation showed no findings for the epididymitis. A toxicological relevance was therefore not assumed.

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (actual dose received)

Based on:

other: solid content of AAS-Loesung

Sex:

male/female

2

Dose descriptor:

NOAEL

Effect level:

2 050 mg/kg bw/day (actual dose received)

Based on:

test mat.

Remarks:

AAS-Loesung

Sex:

male/female

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Executive summary:

In a repeated dose toxicity study in rats (Wistar, OECD TG 407) the test item was administered via gavage to 5 rats/sex/dose at 0, 100, 300, 1000 mg/kg bw for 4 weeks. For preparation of test substance formulations (vehicle: demineralized water) the solid content of AAS-Loesung (48.8%) was taken into account. Up to and including 1000 mg/kg bw no mortality occured. The behavior and clinical appearance of the rats were not influenced by the treatment up to and including 1000 mg/kg in both sexes. Body weight, food and water intake, clinical chemistry, organ weights, hematology, clinical chemistry and histopathology gave no indication of toxicologically relevant treatment-related findings. The results from Functional Observational Battery (FOB) measurements in males and females receiving up to and including 1000 mg/kg bw did not differ from the control animals. Motor and Locomotor Activity (MA/LMA) tests did not indicate neurotoxicity up to and including 1000 mg/kg.

Therefore, under the conditions of the present study, the NOAEL for male and female rats was 1000 mg/kg bw, corresponding to 2050 mg AAS-Loesung/kg bw.