(6R-trans)-7-amino-3-(hydroxymethyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

Endpoint summary

Description of key information

The substance has a low acute toxicity to rats when applied orally or by inhalation.

LD50oral > 2000 mg/kg bw

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:

1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- CD-rats (Crl:CDRBR), Sprague Dawley, SPF.
- Supplier: Charles River Wiga GmbH, D-97633 Sulzfeld.
- Justification for selection of the species: rats are recommended by the Guidelines.
- Number of animals and sex: 2 males and 2 females (preliminary test).
- 5 males and 5 females (main study).
- Age: approximately 8 weeks at time of administration.
- Body weight: 171 - 248 g

ENVIRONMENTAL CONDITIONS
Hygiene: improved conventional conditions.
Room number: EHl-22.
Room temperature: average of 23 °C.
Relative humidity: average of 55 %.
Air exchange: 12 per hour.
Light: artificial light from 6 a.m. to 6 p.m.
Cages: single caging in Makrolon cages type ill (39 cm x 23 cm x 15 cm). Wire mesh lids.
Bedding material: Aspen wood chips, type "4 HV" (Finn Tapvei Ky, SF-73600 Kaavi), autoclaved.
Feed: Altromin 1314 FORTE, gamma irradiated with 25 kGy 60Co, ad libitum (Producer: Altromin GmbH, D-32791 Lage).
Exception: Feed was withdrawn the evening before application and was offered again about three hours after administration of the test substance. Random samples of the feed are analysed for contaminants by Altromin, D-32791 Lage.
Water: tap water, offered in Makrolon bottles with stainless steel canules, ad libitum.
Identification: labelling with felt-tipped pen on the tail and on the cage.
Acclimatization: 6 days.

Route of administration:

oral: gavage

Vehicle:

carbowaxe

Details on oral exposure:

Peroral administration was performed within maximum 14 minutes after preparation of the test substance suspension once in the morning by stomach intubation using a metal gavage.
The test substance suspension was stirred during the time of administration.

Doses:

2000 mg/kg bw.

No. of animals per sex per dose:

2 males and 2 females (preliminary test).
5 males and 5 females (main study).

Control animals:

no

Details on study design:

The sequence of dosing of the test substance was:
Step 1: 1000 mg/kg bw. one male and one female
Step 2: 2000 mg/Kg/bw. one male and one female
Step 3: 2000 mg/kg(bw. five males and 5 females

Statistics:

No.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

All animals, i.e. 5 males and 5 females, survived until the scheduled termination of 14 days p.a.

Clinical signs:

All animals were normal during the whole observation period.

Body weight:

Body weight and body weight gain were inconspicuous in all animals at the scheduled examination terms.

Gross pathology:

Males: All animals were normal at terminal necropsy.
Females: 415 animals were normal at terminal necropsy. Telangiectasis in the spleen was found in the affected female.

Other findings:

Signs in life and post mortem findings revealed no differences between the sexes in the response to the test substance.

All animals survived until the scheduled termination. No signs of toxicity, attributable to the action of the test substance, were observed in life or post mortem. No difference between the sexes was noted in the response to the test substance. Due to the results obtained in this study the LD50 (oral) in rats of both sexes is higher than 2000 mg of "HACA" per kg body weight.

Interpretation of results:

practically nontoxic

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

No toxic effects of the test substance were noted by signs in life and post mortem at a dose of 2000 mg test substance per kg body weight.The LD50 is >2000 mg/kg body weight.

Executive summary:

The acute toxic class (ATC) method according to the EU- and OECD-guidelines was applied to investigate the acute oral toxicity of sodium phenoxyacetate in rats.

No toxic effects of the test substance were noted by signs in life and post mortem at a dose of 2000 mg test substance per kg body weight. No mortality occurred. As no animals died, the oral LD50 was determined to be > 2000 mg/kg body weight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

Guideline study. The LD50 is not 2000 mg/kg, as one is forced to enter in the field above, but the LD50 > 2000 mg/kg.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

No classification is derived from the results obtained.