Bis(2-ethylhexyl) 2-(4-hydroxy-3,5-dimethoxybenzylidene)malonate

Endpoint summary

Description of key information

The acute toxicity of the test material was investigated in 2 tests in rats after oral and dermal administration. Both acute toxicity tests were performed as limit tests. No toxicity or adverse effects were observed in rats treated with the test material after oral or dermal administration at the limit dose. The tests were performed according to international accepted guidelines and under GLP regulation and, therefore, they were of high quality and well suited for risk assessment in humans.

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:

2003-02-21 to 2003-06-23

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)

Version / remarks:

adopted 17 December 2001

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Version / remarks:

30 September 1996

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

- Test system
Species: Rat, Wistar HsdCpb: WU, males (m) and females (f)
Age: approx. 6 to 8 weeks
Mean initial body weight at the start of the study: 177 g (range from 156 to 196 g).

- Identification and adaptation
Healthy young animals were allocated to the study group at least 7 days before dosing to allow for acclimatization.
The rats were identified by an ear tattoo.

- Housing and diet
The rats were housed in an air-conditioned room of about 25 m^2 in the institute. Lighting was controlled by a timer to provide a 12 hour light - 12 hour dark regime.

The rats were kept separately in type III Makrolon cages with a shelter, placed on mobile racks. Conventional softwood granulate was used
as the bedding. One day before treatment, and up to 24 hours after dosing, metal grids were placed above the softwood granulate.
The cages and the metal grids had been machine-cleaned before the start of the experimental part. The bedding was changed two times per
week.

Temperature and humidity were measured using a thermohygrograph. The room temperature during the experimental period was 22 °C
and the relative atmospheric humidity 44 to 68 %.

Diet was withheld from 17 hours before until up to 4 hours after treatment. At all other times food and tap water from Makrolon drinking
bottles were available to the rats ad libitum.

According to the specifications given by the manufacturer, the diet, Provimi Kliba 3433.0, had been checked by independent laboratories.
Analysis included qualitative and quantitative evaluation for heavy metals, aflatoxins, pesticides, and antibiotics.
The drinking water was periodically analyzed according to the German regulations for human drinking water.

The softwood granulate was analytically checked by independent laboratories.

Route of administration:

oral: gavage

Vehicle:

other: Methocel K4M premium (hydroxypropyl methylcellulose)

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 g/L
- Amount of vehicle (if gavage): 10 mL/kg bw
- Justification for choice of vehicle: standard vehicle for this type of studies

Doses:

2000 mg/kg bw (limit test)

No. of animals per sex per dose:

3 males / 3 females

Control animals:

no

Details on study design:

Observation for clinical symptoms
The behavior and general condition of all rats were monitored for at least 6 hours after administration and then checked daily.

Body weight
All animals were weighed before treatment and on days 2, 4, 6, 8, 11, 13, and 15 of the experimental part.

Pathology
All rats were sacrificed at the end of the experimental part by C02-asphyxia and subjected to a gross pathological investigation.

Statistics and evaluation
The body weight data recording and statistical evaluations were performed using a PC-program. The body weight development of each rat and group was determined. The group mean value was calculated for each measurement and printed on tables.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality observed. All rats survived the observation period.

Clinical signs:

No signs of toxicity were detected in the 3 male and 3 female rats after treatment with 2000 mg/kg of test material.

Body weight:

Body weight development of the treated rats was inconspicuous.

Gross pathology:

At necropsy no organ alterations were seen.

Other findings:

None

Interpretation of results:

GHS criteria not met

Conclusions:

According to the results of this study in rats the test material is not toxic/harmful after acute oral administration i.e. the LD50 value (rat, oral) exceeds the limit dose of 2000 mg/kg body weight.

Executive summary:

Purpose

The purpose of this assay was to provide information on possible health hazards for the test material and serve as a rational basis for risk assessment to the potential of acute oral toxicity of the test item in man.

Study design

This study was performed according to the OECD TG 423 ,,Acute toxic class method" (ATC).

Results

No signs of toxicity were detected in 3 male and 3 female rats after treatment and no rat died.

The gross pathological examination revealed no organ alterations.

Conclusions

According to the results of this study the test material can be allocated to ATC class 0 i.e. the LD50 value exceeds the limit dose of 2000 mg/kg body weight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Quality of whole database:

The study is GLP compliant and of high quality (Klimisch score 1).

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:

2004-09-03 to 2004-12-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

adopted 24 February 1987

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Version / remarks:

29 December 1992

Deviations:

no

Principles of method if other than guideline:

None

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

- Test system
Species: Rat, Wistar HsdCpb: WU, males (m) and females (f)
Age: approx. 9 to 13 weeks

- Identification and adaptation
Healthy young animals were allocated to the study group at least 7 days before dosing to allow for acclimatization.
The rats were identified by an ear punching and additionally with an ear tattoo.

- Housing and diet
The rats were housed in an air-conditioned room of about 25 m^2. Lighting was controlled by a timer to provide a 12 hour light - 12 hour dark regime.

The rats were kept separately in type III Makrolon cages with a shelter, placed on mobile racks. Conventional softwood granulate was used
as the bedding. One day before treatment, and up to 24 hours after dosing, metal grids were placed above the softwood granulate.
The cages and the metal grids had been machine-cleaned before the start of the experimental part. The bedding was changed two times per
week.

Temperature and humidity were measured using a thermohygrograph. The room temperature during the experimental period was 22 to 24 °C
and the relative atmospheric humidity 42 to 62 %.

Diet, Provimi Kliba 3433.0, and tap water from Makrolon drinking bottles were available to the rats ad libitum.

The die had been checked according to the specifications of the manufacturer by independent laboratories.
Analysis included qualitative and quantitative evaluation for heavy metals, aflatoxins, pesticides, and antibiotics.
The drinking water was periodically analyzed according to the German regulations for human drinking water.

The softwood granulate was analytically checked by independent laboratories.

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

The backs and abdomens of the rats were shaved with an electric hair clipper not later than one hour before treatment.
The test material was prepared, spread on the shaven skin in an area of 6 x 6 cm, and covered with a gauze patch. This was kept in place by a self-adhesive fabric (Fixomull® stretch, Beiersdorf). The time of exposure was 24 hours. Then the gauze and adhesive fabric were removed and any remaining test material was wiped off carefully.

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 (males) / 5 (females)

Control animals:

no

Details on study design:

-- Observation for clinical symptoms
On the day of treatment the general condition and motility of the rats were slightly affected by the tape. It was difficult to distinguish between slight clinical findings and reactions due to fixation by the tape. The behavior and general condition of all rats were monitored for at least 6 hours after administration and then checked daily.

-- Body weight
All animals were weighed before treatment and on days 2, 4, 6, 8, 11, 13, and 15 of the experimental part.

-- Pathology
All rats were sacrificed at the end of the experimental part by CO2-asphyxia. They were subjected to a gross pathological investigation.

Statistics:

The body weight data were processed using a PC-program. The body weight development of each rat and group was determined. The group mean value was calculated for each measurement and printed on tables.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

One animal was accidentally hurt removing the gauze patch and was sacrificed for human reasons on day 1 of the experimental part.
All the other rats survived the observation period.

Clinical signs:

No signs of toxicity were detected in the 5 male and 5 female rats after dermal treatment with 2000 mg/kg of the test item.

Body weight:

The body weight development of the treated rats was inconspicuous.

Gross pathology:

At necropsy, no organ alterations were seen.

Other findings:

None

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the result of this study in rats, the test substance can be considered to have no acute toxic potential after dermal administration and the LD50 value is higher than the limit dose of 2000 mg/kg.

Executive summary:

Purpose

The purpose of this assay was to provide information on possible health hazards of the test item and serve as a rational basis for risk assessment to the potential of acute dermal toxicity of the test item in man.

Study design

The study was performed according to the OECD Guideline for Testing of Chemicals, No. 402 and according to Commission Directive 92/69/EEC B3.

Results

No signs of toxicity were detected in the rats (4 males and 5 females) after treatment with 2000 mg/kg. One animal was accidentally hurt removing the gauze patch and was sacrificed for human reasons on day 1 of the experimental part. All the other rats survived the observation period.

The body weight development was inconspicuous The gross pathological examination revealed no organ alterations.

Conclusions

Based on the result of this study, the test item can be considered to have no acute toxic potential and the expected LD50 value is higher than 2000 mg/kg after dermal administration to rats.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Quality of whole database:

The study is GLP compliant and of high quality (Klimisch score 1).

Additional information

Oral route of administration

The test substance was tested for acute toxicity in rats after oral administration of 2000 mg/kg body weight. This study was performed according to the ,,Acute toxic class method" (ATC).

No signs of toxicity were detected in the 3 male and 3 female rats after treatment and no rat died. The gross pathological examination revealed no organ alterations.

Based on the result of this study, the test item can be considered to have no acute toxic potential and to have a LD50 value higher than 2000 mg/kg after oral administration to rats.

Dermal route of administration

The test substance was tested for acute toxicity in 5 male and 5 female rats after dermal administration of 2000 mg/kg body weight.

One animal was accidentally hurt removing the gauze patch and was sacrificed for human reasons on day 1 of the experimental part. All the other rats survived the observation period. The body weight development was inconspicuous.The gross pathological examination revealed no organ alterations.

Based on the result of this study, the test item can be considered to have no acute toxic potential and to have a LD50 value higher than 2000 mg/kg after dermal application to rats.

Justification for selection of acute toxicity – oral endpoint
Only one study available

Justification for selection of acute toxicity – dermal endpoint
Only one study available.

Justification for classification or non-classification

Based on the results for acute oral and dermal toxicity in rats, the test item is considered to have no acute toxic potential. The LD50 values exceed 2000 mg/kg bw after oral and dermal administration to rats, respectively. Therefore, the test item is not classified according to EU Directive 67/548/EC amended and repealed by EU Regulation No.1272/2008 and CLP.