4-[(4-ethoxyphenyl)amino]-N,N-dimethyl-3-nitrobenzenesulphonamide

Endpoint summary

Description of key information

The oral LD50 of the test substance was found to be > 2000 mg/kg bw  in rats (1814 mg/kg based on a.i.)

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

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

Adequacy of study:

key study

Study period:

From 28 July, 1993 to 11 August, 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The test was conducted on a similar substance. The complete justification for the read across is attached at section 13.

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: BRL, Biological Research Laboratories Ltd. Wolferstrasse 4, CH-4414 Fullinsdorf, Switzerland
- Age at study initiation: Approx. 10 weeks
- Weight at study initiation: Males(♂) : 231 - 268 g; Females(♀): 168 - 192 g
- Fasting period before study: 16 to 22 h (access to water was not interrupted). Food was presented approx. 3 to 4 h after dosing
- Housing: Group housing of 5 animals/sex/cage in labelled polycarbonate cages containing purified sawdust as bedding material (Woody SPF, supplied by B.M.I., Helmond, The Netherlands)
- Diet: Standard pelleted laboratory animal diet (Kliba 343 from Klingentalmühle Ag, Kaiseraugst, Switzerland) (free access, except for overnight fasting period)
- Water: Tap-water ad libitum.
- Acclimation period: At least one week
-Identification: By individual earmark.
-Randomisation: Randomly selected at time of delivery in groups of five.

ENVIRONMENTAL CONDITIONS
- Temperature: 21 °C
- Humidity: 55%
- Air changes: 15 air changes/h
- Photoperiod: 12 h/12 h (music during light period)

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

1%

Details on oral exposure:

Test substance preparation:
The test substance was placed into a glass beaker on a tared Mettler analytical balance and carboxymethyl cellulose 1% was added. A weight/weight suspension was prepared using a magnetic stirrer, a mechanical stirrer and an electric blender. The preparation was made immediately prior to each dosing.
Dose volume: 10 mL/kg bw

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 per sex per dose

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 15 d
- Necropsy of survivors performed: yes; all animals were necropsied. All animals surviving to the end of the observation period were sacrificed by oxygen/carbon dioxide asphyxiation.
- Other examinations performed: clinical signs, body weight, organ weights, histopathology, other:
- Mortality / Viability: At least three times each Day.
- Body Weights: Test Days 1 (pre-administration), 8 and 15
- Clinical Signs: Each animal was examined for changes to treatment with particular attention paid to changes in behaviour, respiration, motility, body posture, motor susceptibility, skin, eyes, nose and fur. Observations were performed four times during Day 1, and once daily during Days 2 - 15. All abnormalities were recorded.

Statistics:

No data

Preliminary study:

No data

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 1 814 mg/kg bw

Based on:

act. ingr.

Mortality:

No mortality occurred during the study period.

Clinical signs:

other: No clinical signs of ill health or behavioural changes were observed during the study period.

Gross pathology:

Macroscopic post mortem examination of the animals at termination did not reveal any significant abnormalities. Renal pelvic dilation is a common finding in animals of this age and strain and therefore considered of no toxicological significance.

Other findings:

No data

Interpretation of results:

other: Not classified according to the CLP Regulation

Conclusions:

Under the study conditions, the oral LD50 of the test substance was found to be > 2000 mg/kg bw (i.e. ca. > 1814 mg a.i./kg bw) in rats.

Executive summary:

The study was conducted in order to assess the acute oral toxicity of the test substance in Wistar rats according to OECD Guideline 401 and EU Method B.1 in compliance with GLP.

Two groups of 5 female or 5 male rats received a single oral (gavage) dose of 2000 mg/kg bw of test substance. Parameters assessed included mortality, clinical observations, body weight and necropsy findings in all animals over a 15 d observation period.

No mortality occurred, no clinical signs were observed and no significant macroscopic abnormalities were seen at necropsy except renal pelvic dilation which is a common finding in animals of this age and strain and was therefore considered to be of no toxicological significance. Further, normal body weight gain was noted in all females over the first week. However, slightly reduced body weight gain was observed among females over Week 2 compared to Week 1.

Under the study conditions, the oral LD50 of the test substance was > 2000 mg/kg bw (i.e. ca. > 1814 mg a.i./kg bw) in rats.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

According to the CLP Regulation (EC n. 1272/2008) acute toxicity means those adverse effects occurring following oral or dermal administration of a single dose of a substance or a mixture, or multiple doses given within 24 hours, or an inhalation exposure of 4 hours. The substance is not capable to produce adverse effects after acute administration by oral route, therefore no classification is warranted.