2'-[2,4-dichloro-5-(1-methylethoxy)phenyl]-2,2-dimethylpropionohydrazide

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study is a screening test but followed international guidance requirements with acceptable restrictions. As this study is more recent and more details about the experimental conditions were available compared to the study performed in 1998, the study performed in 2006 was considered as the more reliable and relevant and considered as the Key study.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Principles of method if other than guideline:

Another screening study on the test material was available showing a LD 50 of approximately 25 mg/kg bw (study considered as a supporting study in the present dossier). The study in 2006 was performed in order to refine the result obtained previously. 3 different single oral doses were administered by gavage to 3 different female rat groups.

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2'-[2,4-dichloro-5-(1-methylethoxy)phenyl]-2,2-dimethylpropionohydrazide

EC Number:

257-027-8

EC Name:

2'-[2,4-dichloro-5-(1-methylethoxy)phenyl]-2,2-dimethylpropionohydrazide

Cas Number:

51167-18-1

Molecular formula:

C14H20Cl2N2O2

IUPAC Name:

N'-(2,4-dichloro-5-isopropoxyphenyl)-2,2-dimethylpropanehydrazide

Test material form:

not specified

Details on test material:

- Name of test material (as cited in study report): HTMA

Test animals

Species:

rat

Strain:

not specified

Sex:

female

Details on test animals or test system and environmental conditions:

- Fasting period before study: overnight

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: aqueous methylcellulose

Details on oral exposure:

VEHICLE
- Amount of vehicle (if gavage): 10 mL/kg bw

Doses:

50; 100 and 200 mg/kg bw

No. of animals per sex per dose:

3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 8 days
- Frequency of observations and weighing: daily observations, weighing on study 1 and at termination
- Necropsy of survivors performed: no
- Other examinations performed: clinical signs, body weight

Statistics:

LD50 Finney calculation

Results and discussion

Preliminary study:

not applicable

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

114.17 mg/kg bw

Based on:

test mat.

Mortality:

At 200 and 100 mg/kg bw, 2/3 animals were sacrificed moribund on the study day 3. At 50 m/Kg bw, no death occurred.

Clinical signs:

other: At 100 and 200 mg/kg bw, before death animals were prostated and had a reduced motor activity. At 50 mg/kg bw, no clinical signs were recorded.

Gross pathology:

no data

Other findings:

no other findings

Any other information on results incl. tables

no other information.

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category III

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the test conditions, 2'-(2,4-Dichloro-5-(1-methylethoxy)phenyl)-2,2-dimethylpropionohydrazide is toxic to the female rat after a single oral dose administration. As the LD50 is 114.17 mg/kg bw, 2'-(2,4-Dichloro-5-(1-methylethoxy)phenyl)-2,2-dimethylpropionohydrazide is classified as Acute tox 3 (H301) according to the Regulation (EC) 1272/2008 (CLP) and as toxic if swallowed (T, R25) according to the Directive 67/548/EEC.

Executive summary:

In an acute oral toxicity screening study, performed similarly to the OECD guideline No. 401, three groups of female rats (3 animals/dose) were given a single oral dose of undiluted 2'-(2,4-Dichloro-5-(1-methylethoxy)phenyl)-2,2-dimethylpropionohydrazide (named as HTMA in the study report) by gavage at the doses of  200; 100 and 50 mg/kg bw. Clinical signs, mortality and body weight gain were checked for a period of up to 8 days. No necropsy was performed.

 

Oral LD₅₀rat (female) = 114.17 mg/kg bw

 

At 200 and 100 mg/kg bw, 2/3 animals were sacrificed moribund on the study day 3. At 50 m/Kg bw, no death occurred. At 100 and 200 mg/kg bw, before death animals were prostated and had a reduced motor activity. At 50 mg/kg bw, no clinical signs were recorded. All animals had a body weight gain between 14 and 19%.

Under the test conditions, 2'-(2,4-Dichloro-5-(1-methylethoxy)phenyl)-2,2-dimethylpropionohydrazide is toxic to the female rat after a single oral dose administration. As the LD50 is 114.17 mg/kg bw, 2'-(2,4-Dichloro-5-(1-methylethoxy)phenyl)-2,2-dimethylpropionohydrazide is classified as Acute tox 3 (H301) according to the Regulation (EC) 1272/2008 (CLP) and as toxic if swallowed (T, R25) according to the Directive 67/548/EEC. This study is considered as acceptable and satisfies the requirement for acute oral toxicity endpoint.