1,2-diethoxybenzene

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 26 July 2005 to 02 August 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Screening test of OECD 423.The observation period was reduced to 7 days, the body weight was recorded on days 1 and 8 only and no macroscopic necropsy examinations were performed.

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:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

: the observation period was reduced to 7 days, the body weight was recorded on days 1 and 8 only and no macroscopic necropsy examinations were performed (screening test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

: the observation period was reduced to 7 days, the body weight was recorded on days 1 and 8 only and no macroscopic necropsy examinations were performed (screening test)

Principles of method if other than guideline:

Not applicable

GLP compliance:

no

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,2-diethoxybenzene

EC Number:

218-089-1

EC Name:

1,2-diethoxybenzene

Cas Number:

2050-46-6

Molecular formula:

C10H14O2

IUPAC Name:

1,2-diethoxybenzene

Test material form:

gas under pressure: refrigerated liquefied gas

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Janvier, Le Genest-Saint-Isle, France
- Age at study initiation: on the day of treatment, the animals will be approximately 8 weeks old.
- Weight at study initiation: 180 to 220 g within a range of +/-20% of the mean body weight.
- Fasting period before study: the animals will be fasted during the night before treatment but will have free access to water. Food will be given back
approximately 4 hours afetr administration of the test item.
- Housing: the animals will be housed in polycarbonate cages with stainless steel lid. Each cage will contain one to seven animals during the acclimation period and three rats of the same group during the treatment period.
- Diet (e.g. ad libitum): SSNIFF R/M-H pelleted diet (SSNIFF Spezialdiäten GmbH, Soest, Germany)
- Water (e.g. ad libitum): tap water
- Acclimation period: at least 5 days before the beginning of the study.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 2°C
- Humidity (%): 30 to 70%
- Air changes (per hr): approximately 12 cycles/hour of filtered, non recycled air.
- Photoperiod (hrs dark / hrs light): 12 hrs dark/12 hrs light

IN-LIFE DATES: no data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: no data
- Amount of vehicle (if gavage): no data
- Justification for choice of vehicle: no data
- Lot/batch no.: no data
- Purity: no data

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg

DOSAGE PREPARATION (if unusual): not applicable

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: taking into account information provided by the sponsor, the starting dose-level was 2000 mg/kg bw.

Doses:

2000 mg/kg

No. of animals per sex per dose:

3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 7 days
- Frequency of observations and weighing: the animals were observed 30 minutes after dosing, periodically during the first 24 hours and then daily
(including weekends and public holidays) for a period of 8 days.The body weight was recorded on days 1 and 8.
- Necropsy of survivors performed: no
- Other examinations performed: clinical signs, body weight and body weight gain.

Statistics:

Not performed.

Results and discussion

Preliminary study:

No mortality was observed in this screening test performed with three female rats at 2000 mg/kg bw. Therefore, the oral LD50 of o-Diethoxybenzene was higher than 2000 mg/kg in rats.

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was recorded during the study (See Table 7.2.1/2)

Clinical signs:

other: Hypoactivity, piloerection and dyspnea were observed in all animals from day 1 up to day 2 in the morning. No clinical signs persisted from day 2 in the evening up to the end of the observation period (day 8).

Gross pathology:

No macroscopic examinations were performed.

Other findings:

No data

Any other information on results incl. tables

Table 7.2.1/2: Number of animals dead 

Dose (mg/kg bw)	Mortality (# dead/total)
	Male	Female	Combined
2000	-	0/3	0/3

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the test conditions of this study, the oral LD50 of o-Diethoxybenzene was higher than 2000 mg/kg in female rats. Based on these results, no classification is warranted according to the criteria of the CLP Regulation (EC) N°1272/2008 and of the Directive 67/548/EEC.

Executive summary:

The acute oral toxicity of o-Diethoxybenzene was determined in an acute toxic class screening assay (C.Pelcot, 2005). The test item was prepared in corn oil and was administered to three female rats (SD) at the dose-level of 2000 mg/kg bw, under a volume of 10 mL/kg. Clinical signs, mortality and body weight gain were checked for a period of up to 7 days following the single administration of the test item. No macroscopic examinations were performed.

No mortality was recorded during the study. Hypoactivity, piloerection and dyspnea were observed in all animals from day 1 up to day2 inthe morning. No clinical signs persisted from day2 inthe evening up to the end of the observation period (day 8). The overall body weight gain of the animals was not affected by treatment with the test item.

Under the test conditions of this study, the oral LD50 of o-Diethoxybenzene was higher than 2000 mg/kg in rats. Based on these results, no classification is warranted according to the criteria of the CLP Regulation (EC) N°1272/2008 and of the Directive 67/548/EEC.

 

This acute oral study (screening) is classified as acceptable. It satisfies the guideline requirement for an acute oral study in the rats.