Bis(p-methoxyphenyl)iodonium bromide

Endpoint summary

Description of key information

The acute toxic class method was carried out involving a stepwise procedure with the use of 2000 mg/kg bw as the starting dose in three female rats. Since three female animals died the test was continued at 300 mg/kg bw dose level on further three female rats. No animal died in the second step at 300 mg/kg bw dose level, further three female rats were treated with the same (300 mg/kg bw) dose. No animal died in the third step, too, so the test was finished, the stopping criteria of Annex 2d of OECD Guideline No. 423. was met. The test item was ranked into the Acute Toxicity, via oral route category 4 according the classes of Globally Harmonized Classification System (GHS).

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 November 2018 - 21 January 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

Animal health: Only healthy animals were used for the study. Health status was certified by the study director.
Room: 13/1
Housing: Group caging (3 animals/cage)
Cage type: Type III. polypropylene/polycarbonate.
Light: 12 hours daily, from 6.00 a.m. to 6.00 p.m.
Temperature: 22 ± 3 °C
Relative humidity: 30 - 70 %
Ventilation: above 10 air exchanges/hour by central air-condition system.
The temperature and relative humidity parameters were recorded daily during the study.

Route of administration:

oral: gavage

Vehicle:

methylcellulose

Remarks:

1 %

Details on oral exposure:

VEHICLE
All doses were formulated in the vehicle. Concentration of formulations was adjusted to maintain a treatment volume of 10 mL/kg bw. The test item was applied in a concentration of 200 and 30 mg/mL. Formulations were prepared just before the administration.
Methyl cellulose solution (1 %)
Methyl cellulose
Batch number: CM2901147
Date of expiration: 29.11.2021
Produced by: Molar Chemicals Kft.

No. of animals per sex per dose:

6 female

Control animals:

no

Preliminary study:

The acute toxic class method was carried out involving a stepwise procedure with the use of 2000 mg/kg bw as the starting dose in three female rats. Since three female animals died the test was continued at 300 mg/kg bw dose level on further three female rats. No animal died in the second step at 300 mg/kg bw dose level, further three female rats were treated with the same (300 mg/kg bw) dose. No animal died in the third step, too, so the test was finished, the stopping criteria of Annex 2d of OECD Guideline No. 423 was met.
Animals were weighed, observed for lethality and toxic symptoms for 14 days after the treatment. Gross pathological examination was carried out in animals died on the treatment day, as well as 15th day after the treatment in survivor animals.

Key result

Sex:

female

Dose descriptor:

approximate LD50

Effect level:

> 300 - < 2 000 mg/kg bw

Based on:

test mat.

Gross pathology:

All animals treated with 2000 mg/kg bw dose spontaneously died during the study and were necropsied on the treatment day.
All animals treated with 300 mg/kg bw dose survived until the scheduled necropsy on Day 15.
External necropsy finding as anus contaminated with watery faeces was found in all animals of group 1 (2000 mg/kg bw). This alteration could be related to indirect systemic toxic effect of test item.
Internal necropsy findings were found in animals of group 1 (2000 mg/kg bw), too. Blushed mucous membrane in the intestines was observed in all animals. Intestines were full of gas in animal No.: 3218. These alterations could be related to systemic toxic effect of test item.
Moderate hydrometra was found in animal No.: 3224 of group 3 (300 mg/kg bw). Hydrometra is physiological finding and connected to the cycle of the animal.
No pathological changes were found related to the effect of the test item during the macroscopic examination of animals treated with 300 mg/kg bw dose.

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

The test item was ranked into classes of Globally Harmonized Classification System (GHS) described in the OECD Guideline No. 423 as below:

Dose (mg/kg bw) Mortality (dead/treated) LD50 (mg/kg bw) GHS category
300 0/6 between 300 and 2000 4

The LD50 cut- off value is 500 mg/kg bw.

Executive summary:

The acute toxic class method was carried out involving a stepwise procedure with the use of 2000 mg/kg bw as the starting dose in three female rats. Since three female animals died the test was continued at 300 mg/kg bw dose level on further three female rats. No animal died in the second step at 300 mg/kg bw dose level, further three female rats were treated with the same (300 mg/kg bw) dose. No animal died in the third step, too, so the test was finished, the stopping criteria of Annex 2d of OECD Guideline No. 423 was met.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

discriminating dose

Value:

300 mg/kg bw