Monalazone disodium

Endpoint summary

Description of key information

Oral LD50 (female; rat) 2500 mg/kg bw

Dermal LD50 (female; rat) 2000 mg/kg bw

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:

18.10.2018-07.12.2018

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

Test type:

acute toxic class method

Limit test:

yes

Specific details on test material used for the study:

Test Item Name : Monalazone Disodium
CAS No. : Proprietary
Molecular Formula : C7H4ClNNa2O4S
Molecular Weight : 279.602 g/mol
Purity as per COA : >99% excluding water
Physical Appearance : White or Off white powder or crystals
Aqueous pH : 8-10
Lot No. : 72617S
Manufactured Date : 26-07-2017
Expiry date : 01-02-2019
Recommended Storage : Ambient (+18 to +36oC)
Photosensitive : Yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Invivo Biosciences, Shed No. 23, Katha No.3169, Assessment No. 154, Kodigehalli Village, Magadi Road, Bangalore-560091, Karnataka, India
- Females (if applicable) nulliparous and non-pregnant
- Age at study initiation: 8 to 9 Weeks
- Weight at study initiation: 165.6 to 192.5 g
- Fasting period before study: overnight (for a maximum of 20 hours) prior to dosing and until 3-4 hours after administration of the test item.
- Housing:Rats were housed individually in standard polysulfone cages (Size: approximately L 425 x B 266 x H 185 mm), with stainless steel top grill having facilities for pelleted food and drinking water in polycarbonate bottle. Additionally, polycarbonate rat huts were placed inside the cage as an enrichment object and were changed along with the cage once a week. Bedding: steam sterilized
- Diet: Ad libitum. Hypro Rat & Mice pellet feed, manufactured by Krishna Valley Agrotech LLP, MIDC Kupwad block, Sangli, Maharashtra, was provided to animals.
- Water: Ad libitum. Deep bore-well water passed through activated charcoal filter and exposed to UV rays in Aquaguard on-line water filter-cum-purifier manufactured by Eureka Forbes Ltd, Mumbai 400 001, India, was provided to animals in polycarbonate bottles with stainless steel sipper tubes.
- Acclimation period: After physical examination for good health and suitability for experiment, the animals were acclimatized 8 days for G1-FTS, 10 days for G1-STS, 12 days for G2-FTS & 12 days for G2-STS, before treatment. Animals were observed once daily during acclimatization period.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 to 25°C
- Humidity (%): 64 to 68%
- Air changes (per hr): 13.5 air changes per hour
- Photoperiod (hrs dark / hrs light): 12-hour light/12-hour dark

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Justification for choice of vehicle: The test item was checked for solubility / suspendability with Milli-Q water Test item formed suspension in Milli-Q water. Hence Milli-Q water was selected as vehicle and was used to prepare the dose formulations.
- The details of dose formulation
Dose (mg/kg) Concentration(mg/mL) Volume of test item
Suspension (mL) Test item quantity (g)
300 30 20 0.6
300 30 20 0.6
2000 200 15 3.0
2000 200 15 3.0

MAXIMUM DOSE VOLUME APPLIED: 2000 mg/kg bw

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: The dose levels were based on the OECD test guidelines and were selected from the series 5 (lowest dose level), 50, 300 and 2000 (highest dose level) mg/kg body weight. As there was no available toxicology information about this test item, Hence, the study was initiated with the starting dose of 300 mg/kg body weight

Doses:

300 and 2000 (highest dose level) mg/kg body weight

No. of animals per sex per dose:

Group Dose
(mg/kg) No. of Rats Sex
G1 (FTS) 300 3 Female
G1 (STS) 300 3 Female
G2 (FTS) 2000 3 Female
G2 (STS) 2000 3 Female

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed five times on test day 1 (day of administration) i.e. at 30 minutes and four times at hourly intervals and once daily during days 2 to 15. The body weights were recorded on test day 1 (pre-administration), day 8 (7 days post administration) and day 15 (14 days post administration).
- Necropsy of survivors performed: yes. Microscopic examination was not carried out as no gross pathological changes were observed.
- Other examinations performed: clinical signs, body weight,gross pathology

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was observed during the study.

Clinical signs:

other: G1 - [300 mg/kg body weight - Treatment (FTS & STS)]: There were no clinical signs observed and there was no mortality. G2 - [2000 mg/kg body weight - Treatment (FTS & STS)]: G2-FTS: there were no clinical signs and pre-terminal deaths G2-STS: Clinical

Gross pathology:

There were no gross pathological changes at necropsy.

Interpretation of results:

GHS criteria not met

Conclusions:

The oral LD50 value of Monalazone Disodium in Wistar rats was established to exceed 2000 mg/kg body weight. According to the OECD 423 test guideline, the LD50 cut-off value was considered to be 2500 mg/kg body weight.

Executive summary:

To determine the acute toxicity, a stepwise procedure was employed with the use of three animals of a single sex (female), at each step. Sufficient information was obtained on the acute toxicity of the test item for its classification. The test item was administered orally to a group of experimental animals at one of the defined doses (i.e. 300 mg/kg body weight) as a first step (G1-FTS). All the rats survived at this step, the test was continued with the same dose of 300 mg/kg body weight (G1-STS), all the rats survived at this step. The dosing was continued with the next higher dose of 2000 mg/kg body weight (G2-FTS). All the rats survived at this step, the test was continued with three additional animals with the same dose of 2000 mg/kg body weight (G2-STS). 2 out of 3 rats survived, hence testing was stopped and the LD₅₀cut-off value was arrived.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 500 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

31 October 2018 - 3 December 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes

Test type:

fixed dose procedure

Specific details on test material used for the study:

Test Item Name : Monalazone Disodium

CAS No. : Proprietary
Molecular Formula : C7H4ClNNa2O4S
Molecular Weight : 279.602 g/mol
Purity as per COA : >99% excluding water

Physical Appearance : White or Off white powder or crystals
Aqueous pH : 8-10
Lot No. : 72617S
Manufactured Date : 26-07-2017
Expiry date : 01-02-2019
Recommended Storage : Ambient (+18 to +36oC)
Photosensitive : Yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Invivo Biosciences, Shed No. 23, Katha No.3169, Assessment No. 154, Kodigehalli Village, Magadi Road, Bangalore-560091, Karnataka, India
- Females (if applicable) nulliparous and non-pregnant
- Age at study initiation: 8 to 9 Weeks
- Weight at study initiation: 208.5 to 216.0 g
- Fasting period before study: overnight (for a maximum of 20 hours) prior to dosing and until 3-4 hours after administration of the test item.
- Housing:Rats were housed individually in standard polysulfone cages (Size: approximately L 425 x B 266 x H 185 mm), with stainless steel top grill having facilities for pelleted food and drinking water in polycarbonate bottle. Additionally, polycarbonate rat huts were placed inside the cage as an enrichment object and were changed along with the cage once a week. Bedding: steam sterilized
- Diet: Ad libitum. Hypro Rat & Mice pellet feed, manufactured by Krishna Valley Agrotech LLP, MIDC Kupwad block, Sangli, Maharashtra, was provided to animals.
- Water: Ad libitum. Deep bore-well water passed through activated charcoal filter and exposed to UV rays in Aquaguard on-line water filter-cum-purifier manufactured by Eureka Forbes Ltd, Mumbai 400001, India, was provided to animals in polycarbonate bottles with stainless steel sipper tubes.
- Acclimation period: After physical examination for good health and suitability for experiment, the rats were acclimatized for eight to fourteen days before treatment for dose range finding and main study respectively under standard laboratory conditions. Animals were observed once daily during acclimatization period.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 to 25°C
- Humidity (%): 64 to 68%
- Air changes (per hr): 14.1 air changes per hour
- Photoperiod (hrs dark / hrs light): 12-hour light/12-hour dark

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: 8 x 5 cm
- % coverage: 10% of body surface
- Type of wrap if used: adhesive tape wound around the torso

REMOVAL OF TEST SUBSTANCE
- Washing (if done): the applied area was washed with deionized water and wiped dry using clean towel
- Time after start of exposure: 24h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):
Group and Dose tested (mg/kg) Study Rat Number Sex Bodyweight(g) Quantity Applied(mg)
G1 200 DRF Rw1981 F 209.0 42
G2 1000 DRF Rw1982 F 208.5 209
G3 2000 DRF Rw1983 F 210.3 421
G3 2000 §Main Rw1984 F 212.9 426
- For solids, paste formed: yes

VEHICLE
- Amount(s) applied (volume or weight with unit): Based on the individual body weight, the test item at the doses of 200, 1000 & 2000 mg/kg body weight was weighed on an aluminium foil and made into a paste by adding sufficient volume (about 0.1 to 0.5 mL) of the Milli-Q water

Duration of exposure:

24 hours

Doses:

Study Group Dose(mg/kg body weight) No. ofRats Sex Rat numbers
DRF G1 200 1 F Rw1981
DRF G2 1000 1 F Rw1982
DRF G3 2000 1 F Rw1983
Main G3 2000 2 F Rw1984 and Rw1985
DRF: Dose Range Finding F: Female

No. of animals per sex per dose:

1 in DRF; 2 in main study

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed for clinical signs and pre-terminal deaths (mortality) once during first 30 minutes after application, and at hourly intervals for 6 hours after application on the day of treatment (day 1) and once daily during Days 2 to 15. In addition, the site of applied area was observed for skin reactions at 24, 48 and 72 hours after removal of test chemical using the Draize criteria. Body weights were recorded at Day 1, 8 and 15.
- Necropsy of survivors performed: yes. Microscopic examination was not carried out as no gross pathological changes were observed.
- Other examinations performed: clinical signs, body weight,organ weights, macroscopic examination

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

no indication of skin irritation up to the relevant limit dose level

Mortality:

No pre-terminal deaths (mortality) observed during the study.

Clinical signs:

other: There were no clinical signs observed during the study.

Gross pathology:

No abnormality was detected at necropsy.

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the present study results, the acute dermal LD50 of Monalazone Disodium is more than 2000 mg/kg body weight in female Wistar rats.

Executive summary:

The objective of this acute dermal toxicity study was to assess the toxicological profile of the test item on application as a single semi-occlusive dermal application to rats. Groups of animals, of a single sex, were exposed to the test chemical in a stepwise procedure using the appropriate fixed doses. A range-finding study was conducted with a single animal at the doses of 200, 1000 and 2000 mg/kg body weight. The initial dose level was selected at the concentration expected to produce clear signs of toxicity without causing severe toxic effects or mortality. Further, the main study was conducted with two additional animals at the dose of 2000 mg/kg body weight. There were no clinical signs and pre-terminal deaths (mortality) observed during the study. There were no skin reactions at the site of application at 24, 48 and 72 hours after test patch removal (as per draize method).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Acute oral toxicity

The Study by Suman, M.V. (2018) was conducted in accordance with the OECD Guideline for Testing of Chemicals, Section 4, No. 423,“Acute Oral Toxicity – Acute Toxic Class Method”. To determine the acute toxicity, a stepwise procedure was employed with the use of three animals of a single sex (female), at each step. Sufficient information was obtained on the acute toxicity of the test item for its classification. The test item was administered orally to a group of experimental animals at one of the defined doses (i.e. 300 mg/kg body weight) as a first step (G1-FTS). All the rats survived at this step, the test was continued with the same dose of 300 mg/kg body weight (G1-STS), all the rats survived at this step. The dosing was continued with the next higher dose of 2000 mg/kg body weight (G2-FTS). All the rats survived at this step, the test was continued with three additional animals with the same dose of 2000 mg/kg body weight (G2-STS). 2 out of 3 rats survived, hence testing was stopped and the LD50cut-off value was arrived. Based on the results of the present study, the acute oral LD50 of Monalazone Disodium is 2500 mg/kg as per the LD cut-off value.

 

Acute dermal toxicity

The Study by Suman, M.V. (2018) was conducted in accordance with the OECD Guideline for Testing of Chemicals, Section 4, No. 402, “Acute Dermal Toxicity: Fixed dose procedure”. There was no information available on the toxicity of the test item. Hence, a starting dose of 200 mg/kg body weight was selected. Hence, a starting dose of 200 mg/kg body weight was tested with 1 female rat (dose range finding study). As there was no mortality at this dose range finding study as per Annexure 1 of the guideline the dose range finding study was continued with 1 female rat (dose range finding study) at the next higher dose of 1000 mg/kg body weight. There was no mortality, the dose range finding study was continued with 1 female rat (dose range finding study) at the next higher dose of 2000 mg/kg body weight. There was no mortality, the test was continued with the main study with 2 animals at the dose of 2000 mg/kg body weight to confirm the classification.There was no test item-related mortality.

Based on the present study results, the acute dermal LD50 of Monalazone Disodium is more than 2000 mg/kg body weight in female Wistar rats.

Justification for classification or non-classification

Based on these results, Monalazone Disodium does not have to be classified and has no obligatory labelling requirement for acute toxicity according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2015) (including all amendments) and Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments).