Carbonic acid, C,C'-[4-(2-bromoacetyl)-1,3-phenylene] C,C'-dimethyl ester

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29.12.2014 - 19.03.2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-(2-bromoacetyl)-3-[(methoxycarbonyl)oxy]phenyl methyl carbonate

EC Number:

807-596-9

Cas Number:

1428451-07-3

Molecular formula:

C12H11BrO7

IUPAC Name:

4-(2-bromoacetyl)-3-[(methoxycarbonyl)oxy]phenyl methyl carbonate

Test material form:

solid: bulk

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, 97633 Sulzfeld, Germany
- Age at study initiation: 8-15 weeks old
- Weight at study initiation:
Step1: animals no. 1 - 3: 151 - 173 g
Step2: animals no. 4 - 6: 176 - 187 g
Step3: animals no. 7 - 9: 130 - 138 g
- Fasting period before study:Prior to the administration food was withheld from the test animals for 16 to 19 hours (access to water was permitted). Following the period of fasting the animals were weighed and the test item was administered. Food was provided again approximately 4 hours post dosing.
- Housing: The animals were kept in groups in IVC cages, type III H, polysulphone cages on Altromin saw fibre bedding (lot no. 02102140831)
- Diet (e.g. ad libitum): Free access to Altromin 1324 maintenance diet for rats and mice (lot no. 1239)
- Water (e.g. ad libitum): Free access to tap water, sulphur acidified to a pH value of approximately 2.8 (drinking water, municipal residue control, microbiological controls at regular intervals)
- Acclimation period: Adequate acclimatisation period (at least five days) under laboratory conditions

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 °C
- Humidity (%): 55 ± 10%
- Air changes (per hr): 10 x / hour
- Photoperiod (hrs dark / hrs light): Artificial light, sequence being 12 hours light, 12 hours dark

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

cotton seed oil

Details on oral exposure:

In order to get the test item in a solution or suspension, which is applicable to the animals, aqua ad injectionem (sterile water) was tested first but could not yielded to an applicable formulation. Therefore, cottonseed oil (Sigma-Aldrich, lot no. MKBQ5465V, expiry date: 02 March 2015) was evaluated as vehicle and was considered to be adequate.
A suspension with the vehicle was prepared by subjecting it to an ultrasonic bath for 30 min at 37 °C, then to a hot water bath for 10 min at 60 °C and finally homogenising it for 1-2 min using a homogeniser.
Homogeneity of the test item in the vehicle was maintained by vortexing the prepared suspension thoroughly before each dose administration.
For all animals of the first step, 0.3 g of the test item was suspended with the vehicle to gain a final volume of 10 mL and to achieve a dose of 300 mg/kg body weight at a dose volume of 10 mL/kg body weight.
For all animals of the second and third steps, 2 g of the test item was suspended with the vehicle to gain a final volume of 10 mL and to achieve a dose of 2000 mg/kg body weight at a dose volume of 10 mL/kg body weight.
The dose formulations were made shortly before each dosing occasion.

Doses:

300 and 2000 mg/kg body weight

No. of animals per sex per dose:

3 females (nulliparous and non pregnant) per dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were weighed on day 1 (prior to the administration) and on days 8 and 15.
- Necropsy of survivors performed: yes
- Clinical Examination: A careful clinical examination was made several times on the day of dosing (at least once during the first 30 minutes and with special attention given during the first 4 hours post-dose). As soon as symptoms were noticed they were recorded. Thereafter, the animals were observed for clinical signs once daily until the end of the observation period. All abnormalities were recorded. Cageside observations included changes in the skin and fur, eyes and mucous membranes. Also respiratory, circulatory, autonomic and central nervous systems and somatomotor activity and behaviour pattern were examined. Particular attention was directed to observations of tremor, convulsions, salivation, diarrhoea, lethargy, sleep and coma.
- Pathology: At the end of the observation period the animals were sacrificed with an overdosage of pentobarbital injected intraperitoneally (Narcoren®, Merial; lot no.: 236014; expiry date: 31/01/2017) at a dosage of 250-400 mg/kg bw. All animals were subjected to gross necropsy and examined macroscopically for gross pathological changes. In absence of gross pathological changes no tissues were preserved for a possible histopathological evaluation.

Statistics:

no data

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

5 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: LD50 cut-off (rat): 5000 mg/ kg bw

Mortality:

All animals treated with the test item survived until the end of the study.

Clinical signs:

other: All animals of the first step treated with the test item at a dose of 300 mg/kg bw survived until the end of the study without showing any severe signs of toxicity. The animals of the second and the third steps treated all with the test item at a dose of

Gross pathology:

With the exception of acute injection of blood vessels in the abdominal region, which is due to the euthanasia injection, no specific gross pathological changes were recorded for any animal.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of the present study, a single oral application of the test item 2',4'-Bis(methoxycarbonyloxy)-2-brom-acetophenone to rats at a dose of 300 mg/kg body weight was associated with slight signs of toxicity but no mortality and a dose of 2000 mg/kg body weight with signs of toxicity but no mortality.
The median lethal dose of 2',4'-Bis(methoxycarbonyloxy)-2-brom-acetophenone after a single oral administration to female rats, observed over a period of 14 days is: LD50 cut-off (rat): 5000 mg/ kg bw

Executive summary:

In an acute oral toxicity study according to OECD 423 with the test item 2',4'-Bis(methoxycarbonyloxy)-2-brom-acetophenone one group of three female WISTAR Crl: WI(Han) rats, was treated with the test item by oral gavage administration at a dosage of 300 mg/kg body weight. The test item was suspended with the vehicle cottonseed oil at a concentration of 0.03 g/mL and administered at a dose volume of 10 mL/kg.

Two groups, each of three female WISTAR Crl: WI(Han) rats, were treated with the test item by oral gavage administration at a dosage of 2000 mg/kg body weight. The test item was suspended with the vehicle cottonseed oil at a concentration of 0.2 g/mL and administered at a dose volume of 10 mL/kg.

All animals were examined for clinical signs several times on the day of dosing and once daily until the end of the observation period. Their body weights were recorded on day 1 (prior to the administration) and on days 8 and 15. All animals were necropsied and examined macroscopically.

All animals of the first step treated with the test item at a dose of 300 mg/kg bw survived until the end of the study. Only slight signs of toxicity were noted in one animal (slight weight loss during the observation period).

The animals of the second and the third steps all treated with the test item at a dose of 2000 mg/kg bw survived until the end of the study showing signs of toxicity, which were fully reversible within 2 days (animals of the second step) or 3 days (animals of the third step) post dose. The most relevant clinical findings recorded in these steps were reduced spontaneous activity, piloerection, kyphosis, eyes half closed, wasp waist and bradykinesia.

Throughout the 14-day observation period, the weight gain of the animals was within the normal range of variation for this strain, except for one animal which showed a weight loss of 4% during the second week.

At necropsy, no treatment-related macroscopic findings were observed in any animal of any step.

Therefore the median lethal dose of 2',4'-Bis(methoxycarbonyloxy)-2-brom-acetophenone after a single oral administration to female rats, observed over a period of 14 days is: LD50 cut-off (rat): 5000 mg/ kg bw