7-(diethylamino)-4-methyl-2-benzopyrone

Endpoint summary

Description of key information

Acute oral toxicity: 

The acute oral toxicity dose (LD50) was considered based on different studies conducted on rats for the test chemical. The LD50 value is 5000 mg/kg bw. The study concluded that the LD50 value is >2000 mg/kg bw, for acute oral toxicity. Thus, comparing this value with the criteria of CLP regulation, the given test chemical cannot be classified for acute oral toxicity.

Acute Inhalation Toxicity:

The acute inhalation toxicity study need not be conducted because exposure to humans via inhalation route is not likely taking into account due to low vapour pressure of the test chemical, which is reported to be 0.00257 Pa. Thus, exposure to inhalable dust, mist and vapour of the chemical is highly unlikely. Therefore this study is considered for waiver. 

 

Acute Dermal toxicity:

The acute dermal toxicity dose (LD50) was considered based on different studies conducted on rats for the given test chemical. The studies concluded that LD50 value is >2000 mg/kg bw, for acute dermal toxicity. Thus, comparing this value with the criteria of CLP regulation, the given test chemical cannot be classified for acute dermal toxicity.

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer-reivewed journal

Qualifier:

equivalent or similar to guideline

Guideline:

other: as below

Principles of method if other than guideline:

Acute oral toxicity study of the given test chemical in rats.

GLP compliance:

not specified

Test type:

other: not specified

Limit test:

no

Specific details on test material used for the study:

- Name of test material (as cited in study report): 4-Methyl-7-diethylaminocoumarin
- Molecular formula (if other than submission substance): C14H17NO2
- Molecular weight (if other than submission substance): 231.2933 g/mole
- Substance type: Organic

Species:

rat

Strain:

not specified

Sex:

not specified

Details on test animals or test system and environmental conditions:

not specified

Route of administration:

oral: unspecified

Vehicle:

not specified

Details on oral exposure:

not specified

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

not specified

Control animals:

not specified

Details on study design:

not specified

Statistics:

not specified

Preliminary study:

not specified

Sex:

not specified

Dose descriptor:

LD50

Effect level:

5 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No mortality was observed

Mortality:

50% mortality was observed in treated rats at 5000 mg/kg bw.

Clinical signs:

other: not specified

Gross pathology:

not specified

Other findings:

not specified

Interpretation of results:

other: Not classified

Conclusions:

The acute oral LD50 value was considered to be 5000 mg/kg bw, when rats were treated with the given test chemical orally.

Executive summary:

In a acute oral toxicity study, rats were treated with the given test chemical at the concentration of 5000 mg/kg bw orally. Animals were observed for mortality. 50% mortality was observed in treated rats at 5000 mg/kg bw. Therefore, The acute oral LD50 value was considered to be 5000 mg/kg bw, when rats were treated with the given test chemical orally.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

5 000 mg/kg bw

Quality of whole database:

Data is Klimisch 2 and from peer-reviewed journal.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because exposure of humans via inhalation is not likely taking into account the vapour pressure of the substance and/or the possibility of exposure to aerosols, particles or droplets of an inhalable size

Endpoint conclusion

Quality of whole database:

Waiver

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Experimental data from various test chemicals

Justification for type of information:

Data is summarized based on the available information from various test chemicals.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: As mentioned below

Principles of method if other than guideline:

WoE report is based on 2 acute dermal toxicity studies as- WoE 2 and WoE 3.
Acute dermal toxicity test was carried out to study the effects of the test chemicals on rodents.

GLP compliance:

not specified

Test type:

other: not specified

Limit test:

no

Species:

rat

Strain:

other: 2. Wistar 3. Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

2. TEST ANIMALS
- Source: In-House Bred at sa-FORD, Animal Facility (CPCSEA Registration No. 1256/bc/09/CPCSEA)
- Age at study initiation: No data available
- Weight at study initiation: Male:Minimum: 240 g and Maximum: 280 g , Female:Minimum: 222 g and Maximum: 239 g
- Fasting period before study:No data available
- Housing: Animals were housed three per polycarbonate cage of size 37 [cm] x 21 [cm], height 20 [cm] and identified by toe pad micro tattooing and cage cards. Individual cage cards were labelled with study no., study type, test system, group, dose, sex, animal number experimental start date, dosing date and completion date.
- Diet (e.g. ad libitum): conventional laboratory rodent diet (Nutrivet Life Sciences, Pune) ad libitum. Batch No: 040316., ad libitum
- Water (e.g. ad libitum): Aqua guard filtered tap water, ad libitum
- Acclimation period:7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C):Minimum: 19.80 °C - Maximum: 22.80 °C
- Humidity (%):Minimum: 47.10% - Maximum: 68.60%
- Air changes (per hr):12 hour light and 12 hour dark
- Photoperiod (hrs dark / hrs light):More than 12 changes per hour

IN-LIFE DATES: From: April 19, 2016 To:May 03, 2016
3. TEST ANIMALS
- Source: National Institute of Biosciences, Pune.
- Age at study initiation: Young adult male and female rats aged between 8 – 12 weeks were used.
- Weight at study initiation: The weight range of approximately 215.0 to 254.3 grams at initiation of dosing.
Body weights at the start : Male Mean: 246.28 g (= 100 %); Minimum : 240.9 g (- 2.18 %); Maximum : 254.3 g (+ 3.26 %)
Female Mean: 219.02 g (= 100 %); Minimum : 215.0 g (- 1.84 %); Maximum : 223.4 g (+ 2.00 %)
- Identification: Each rat was individually identified by the cage number.
- Housing: The rats were individually housed in polycarbonate cages with paddy husk as bedding.
- Diet (e.g. ad libitum): Rodent feed supplied by the Nutrivet Life Sciences, Pune, was provided ad libitum from individual feeders.
- Water (e.g. ad libitum): Water was provided ad libitum from individual bottles attached to the cages. All water was from a local source and passed through the reverse osmosis membrane before use.
- Acclimation period: 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19.6 to 21.6 degree centigrade.
- Humidity (%): 55.0% to 58.4%.
- Air changes (per hr): Ten to fifteen air changes per hour.
- Photoperiod (hrs dark / hrs light): An artificial light and dark cycle of 12 hours each was provided to the room.

IN-LIFE DATES: 19-05-2017 to 04-08-2017

Type of coverage:

semiocclusive

Vehicle:

other: 2. distilled water 3. water

Details on dermal exposure:

2. TEST SITE
- Area of exposure: the fur of dorsal area of the trunk
- % coverage: greater than 10% body surface area
- Type of wrap if used: Test item was held in contact with the skin with a porous gauze dressing (Approx. 10% of body surface area of rat) and non-irritating tape throughout a 24-hour exposure period. It was ensured that the animals cannot ingest the test item.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): At the end of the exposure period, residual test item was removed by using distilled water.
- Time after start of exposure:24-hour

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): The test item was applied uniformly over clipped dorsal area of rat skin.
- Concentration (if solution): Individual rat was applied with an amount of test item moistened with 0.2 ml distilled water.

VEHICLE
- Amount(s) applied (volume or weight with unit): 0.2 ml distilled water
3. TEST SITE
- Area of exposure: Trunk (dorsal surface and sides from scapular to pelvic area)
- % coverage: Approximately 10% of the body surface area.
- Type of wrap if used: Porous gauze dressing and non-irritating tape.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Distilled water was used to remove residual test item.

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg bw
- For solids, paste formed: Yes

Duration of exposure:

2. 24-hour
3. 24 hours

Doses:

2. 2000 mg/kg body weight
3. A single dose of 2000 mg of the test item per kilogram of body weight was administered to ten rats (five males and five females).

No. of animals per sex per dose:

2. 5 amle, 5 femlae
3. 10 (5/sex).

Control animals:

not specified

Details on study design:

2. Details on study design
- Duration of observation period following administration: 14 days (or other?): 14 day observation period
- Frequency of observations and weighing:: at 1, 2, 3 and 4 hours post dosing on day 0 (day of dosing) and once a day during the 14 day observation period.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: Yes
3. - Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Twice daily
- Necropsy of survivors performed: Yes
- Other examinations performed: Clinical Observations and General Appearance: Animals were observed for clinical signs, mortality, until sacrifice.
Onset, duration and severity of any sign were recorded. The clinical signs and mortality observations were conducted at 10, 30, 60 minutes, 2, 4 and 6 hours on the day of dosing and once daily thereafter for 14 day. Daily observation was done as far as possible at the same time.
The observations were included general clinical signs, observations of eyes, mucous membranes, respiratory, circulatory system and behavior pattern.

Evaluation of Dermal Reaction: Dermal reaction was observed daily for study period of 14 days.

Body weights: Individual animal body weights were recorded pre-test (prior to administration of the test item), day 7 and at termination on day 14.

Gross Pathology: Necropsy was performed on animals surviving at the end of the study. Macroscopic examination of all the orifices, cavities and tissues were made and the findings were recorded. All animals surviving the study period were sacrificed by the carbon dioxide asphyxiation technique (day 15).

Histopathology: No gross abnormalities were observed in animals sacrificed terminally hence, no histopathology was performed.

Statistics:

2. No statistical analysis was performed since the study was terminated with limit test
3. not specified

Preliminary study:

2. No data
3. not specified

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No effect on survival, Clinical Signs,Local Signs/Skin Reactions, Body Weight and gross pathology

Remarks:

2

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No mortality was observed

Remarks:

3

Mortality:

2. No mortality was observed at limit dose of 2000 mg/kg body weight of test item during the 14 day observation period
3. Sex : Male Group I - Animal treated at the dose level of 2000 mg/kg body weight: All animals survived through the study period of 14 days.
Sex : Female Group I - Animal treated at the dose level of 2000 mg/kg body weight: All animals survived through the study period of 14 days.

Clinical signs:

other: 2. No systemic signs of toxicity were observed at limit dose of 2000 mg/kg body weight of test item during the experimental period No local signs of toxicity (e.g.: Abrasion, Alopecia, Erythema, Oedema, Scale Formation etc.) were observed at limit dose o

Gross pathology:

2. The external and internal gross pathological observation of all terminally sacrificed animals did not show any pathological abnormality
3. Gross pathological examination did not reveal any abnormalities in animals from 2000 mg/kg dose group.

Other findings:

2. No data available
3. - Other observations: Evaluation of Dermal Reaction
Sex : Male Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any skin reaction during the study period of 14 days.
Sex : Female Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any skin reaction during the study period of 14 days.

Interpretation of results:

other: Not classified

Conclusions:

According to CLP regulation, the given test chemical cannot be classified for acute dermal toxicity, as the LD50 value is >2000 mg/kg bw.

Executive summary:

In different studies, the given test chemical has been investigated for acute dermal toxicity to a greater or lesser extent. Often are the studies based on in-vivo experiments in rodents, i.e. most commonly in rats for the given test chemical. The studies are summarized as below –

 

The reported study was mentioned in study report and conducted to determine acute dermal toxicity dose by using the given test chemical according to OECD Guideline 402 (Acute Dermal Toxicity) in 10 male and female Wistar rats at the concentration of 2000 mg/kg bw. The given test chemical (100% pure) was moistened with 0.2 ml distilled water and applied by single dermal application on intact skin of clipped area of rats; the porous gauze dressing was put on to the intact skin of clipped area. This porous gauze dressing was covered with a non-irritating tape. After the 24-hour application period, the dressings were removed and the skin was gently wiped with distilled water. The skin reactions were assessed. The animals were observed daily for mortality and clinical signs, during the acclimatization period and post dosing till the termination. All animals were observed for clinical signs at approximately 1, 2, 3 and 4 hours after treatment on day 0 and once daily during test days 1, 14. Mortality was recorded after application on test day 0 and twice daily during days 1-14 (at least once on the day of sacrifice). Local signs/Skin reactions were observed daily from test days 1-14 (in common with clinical signs). Body weights were recorded on day 0 (prior to application) and on day 7 and 14. All animals were necropsied and examined macroscopically. No mortality was observed in any animal till the end of the experimental period. No systemic signs of toxicity were observed at limit dose of 2000 mg/kg body weight of test item during the experimental period. No local signs of toxicity (e.g.: Abrasion, Alopecia, Erythema, Oedema, Scale Formation etc.) were observed at limit dose of 2000 mg/kg body weight of test item during the experimental period. Mean body weight of male and female animals was observed with gain on day 7 and 14 as compared to day 0. The external and internal gross pathological observation of all terminally sacrificed animals did not show any pathological abnormality. Therefore, the acute dermal toxicity dose (LD50) was considered to be >2000 mg/kg bw, when male and female Wistar rats were treated with the given test chemical by dermal application over the clipped dorsal area of rat skin. Thus, comparing this value with the criteria of CLP regulation, it cannot be classified for acute dermal toxicity.

 

The above study is supported with the study mentioned in study report and the study was designed and conducted to determine the acute dermal toxicity profile of the given test chemical as per OECD Guideline 402 (Acute Dermal Toxicity) in Sprague Dawley rats. The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days. Animals exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment. It was concluded that the acute dermal median lethal dose (LD50) of the given test chemical, when administered to male and female Sprague Dawley rats was considered to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that the given test chemical does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

 

Thus, based on the above summarised studies on test chemical, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, the given test chemical cannot be classified for acute dermal toxicity.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

Data is Klimisch 2 and from handbook or collection of data.

Additional information

Acute oral toxicity:

In different studies, the given test chemical has been investigated for acute oral toxicity to a greater or lesser extent. Often are the studies based on in-vivo experiments in rodents, i.e. most commonly in rats for test chemical. The studies are summarized as below –

 

The reported study was mentioned in peer-reviewed journal, handbook and authoritative database and conducted to determine acute oral toxicity dose by using the given test chemical in rats at the concentration of 5000 mg/kg bw orally. Animals were observed for mortality. 50% mortality was observed in treated rats at 5000 mg/kg bw. Therefore, the acute oral LD50 value was considered to be 5000 mg/kg bw, when rats were treated with the given test chemical orally.

 

The above study is supported with another study mentioned in study report for the given test chemical. The acute oral toxicity study was conducted as per OECD No. 423 guideline in Wistar Rats. A total of twelve female Wistar rats were selected for acute oral toxicity study. The animals were fasted for approximately 17 to 18 hrs prior to dosing and for 3 to 4 hrs post dosing, feed was withheld but drinking water provided ad libitum. The time intervals between dosing were determined by the onset, duration and severity of toxic signs. Initially, three rats of G1 (Step -I) were administered orally a dose of 300 mg/kg body weight; and no mortality were observed in all animals. Hence, another set of three rats of the group G1 (Step-II) were dosed at 300 mg/kg body weight and no mortality were observed in all animals. Based on the results of G1 (Step-I & II), another set of three rats of the group G2 (Step - III) were dosed at 2000 mg/kg body weight. No mortality was observed in all three rats tested. Hence, another set of three rats of the group G2 (Step-IV) were dosed at 2000 mg/kg body weight. No mortality was observed in all three rats tested. Since, there was no mortality in both the steps (III and IV) of G2, further dosing was stopped. Body weights were recorded on day 0 (prior to dosing) 7 and 14. The mean body weight of all the animals of G1 (Step-I & II) treated with 300 mg/kg body weight and G2 (Step III & IV)  treated with 2000 mg/kg body weight was observed with gain on day 7 and 14, as compared to day 0 body weight, weighed prior to dosing. At 300mg/kg body weight all animals of G1 (Step-I & II) were observed to be normal throughout the experimental period. At 2000 mg/kg body weight, animals of G2 (Step III & Step-IV) were observed to be normal throughout the experimental period. During external and internal gross pathological examination, terminally sacrificed animals observed with no abnormalities. Under the conditions of this, the acute oral toxicity dose (LD50) was considered to be >2000 mg/kg bw, when Wistar female rats were treated with the given test chemical via oral gavage route.

 

Both the above studies are further supported with the data mentioned in secondary source for the given test chemical. In an acute oral toxicity study, rats were treated with the given test chemical at the concentration of 2400 mg/kg bw orally. Animals were observed for mortality. 50% mortality was observed in treated rats. Therefore, the acute oral LD50 value was considered to be 2400 mg/kg bw, when rats were treated with the given test chemical orally.

 

Thus, based on the above summarised studies on test chemical, it can be concluded that LD50 value is >2000 mg/kg bw, for acute oral toxicity. Thus, comparing this value with the criteria of CLP regulation, the given test chemical cannot be classified for acute oral toxicity.

 

Acute Inhalation Toxicity:

The acute inhalation toxicity study need not be conducted because exposure to humans via inhalation route is not likely taking into account due to low vapour pressure of the test chemical, which is reported to be 0.00257 Pa. Thus, exposure to inhalable dust, mist and vapour of the chemical is highly unlikely. Therefore this study is considered for waiver. 

 

Acute Dermal Toxicity:

In different studies, the given test chemical has been investigated for acute dermal toxicity to a greater or lesser extent. Often are the studies based on in-vivo experiments in rodents, i.e. most commonly in rats for the given test chemical. The studies are summarized as below –

 

The reported study was mentioned in study report and conducted to determine acute dermal toxicity dose by using the given test chemical according to OECD Guideline 402 (Acute Dermal Toxicity) in 10 male and female Wistar rats at the concentration of 2000 mg/kg bw. The given test chemical (100% pure) was moistened with 0.2 ml distilled water and applied by single dermal application on intact skin of clipped area of rats; the porous gauze dressing was put on to the intact skin of clipped area. This porous gauze dressing was covered with a non-irritating tape. After the 24-hour application period, the dressings were removed and the skin was gently wiped with distilled water. The skin reactions were assessed. The animals were observed daily for mortality and clinical signs, during the acclimatization period and post dosing till the termination. All animals were observed for clinical signs at approximately 1, 2, 3 and 4 hours after treatment on day 0 and once daily during test days 1, 14. Mortality was recorded after application on test day 0 and twice daily during days 1-14 (at least once on the day of sacrifice). Local signs/Skin reactions were observed daily from test days 1-14 (in common with clinical signs). Body weights were recorded on day 0 (prior to application) and on day 7 and 14. All animals were necropsied and examined macroscopically. No mortality was observed in any animal till the end of the experimental period. No systemic signs of toxicity were observed at limit dose of 2000 mg/kg body weight of test item during the experimental period. No local signs of toxicity (e.g.: Abrasion, Alopecia, Erythema, Oedema, Scale Formation etc.) were observed at limit dose of 2000 mg/kg body weight of test item during the experimental period. Mean body weight of male and female animals was observed with gain on day 7 and 14 as compared to day 0. The external and internal gross pathological observation of all terminally sacrificed animals did not show any pathological abnormality. Therefore, the acute dermal toxicity dose (LD50) was considered to be >2000 mg/kg bw, when male and female Wistar rats were treated with the given test chemical by dermal application over the clipped dorsal area of rat skin. Thus, comparing this value with the criteria of CLP regulation, it cannot be classified for acute dermal toxicity.

 

The above study is supported with the study mentioned in study report and the study was designed and conducted to determine the acute dermal toxicity profile of the given test chemical as per OECD Guideline 402 (Acute Dermal Toxicity) in Sprague Dawley rats. The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days. Animals exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment. It was concluded that the acute dermal median lethal dose (LD50) of the given test chemical, when administered to male and female Sprague Dawley rats was considered to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that the given test chemical does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

 

Thus, based on the above summarised studies on test chemical, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, the given test chemical cannot be classified for acute dermal toxicity.

 

Justification for classification or non-classification

Based on the above studies on test chemical, it can be concluded that LD50 value is >2000 mg/kg bw, for acute oral and acute dermal toxicity. Thus, comparing this value with the criteria of CLP regulation, the given test chemical cannot be classified for acute oral and acute dermal toxicity. For acute inhalation toxicity wavier was added so, not possible to classify.