h

EVALUATION OF ACUTE ORAL TOXICITY – ACUTE TOXIC CLASS METHOD

OECD 423

PRINCIPLE OF THE TEST

It is the principle of the test that, based on a stepwise procedure with the use of a minimum number of animals per step, sufficient information is obtained on the acute toxicity of the test substance to enable its classification. The substance is administered orally to a group of experimental animals at one of the defined doses(5, 50, 300 and 2000 mg/kb b.w.). The substance is tested using a stepwise procedure, each step using three animals of a single sex (normally females). Absence or presence of compound-related mortality of the animals dosed at one step will determine the next step, i.e.;

  • no further testing is needed,
  • dosing of three additional animals, with the same dose
  • dosing of three additional animals at the next higher or the next lower dose level.

The method will enable a judgement with respect to classifying the test substance to one of a series of toxicity classes defined by fixed LD50 cut-off values.

Observation RESULTS

Animals are observed individually after dosing at least once during the first 30 minutes, periodically during the first 24 hours, with special attention given during the first 4 hours, and daily thereafter, for a total of 14 days, except where they need to be removed from the study and humanely killed for animal welfare reasons or are found dead. However, the duration of observation should not be

fixed rigidly. It should be determined by the toxic reactions, time of onset and length of recovery period, and may thus be extended when considered necessary. The times at which signs of toxicity appear and disappear are important, especially if there is a tendency for toxic signs to be delayed. All observations are systematically recorded with individual records being maintained for each animal

Individual animal data should be provided. Additionally, all data should be summarised in tabular form, showing for each test group the number of animals used, the number of animals displaying signs of toxicity, the number of animals found dead during the test or killed for humane reasons, time of death of individual animals, a description and the time course of toxic effects and reversibility, and necropsy findings

CONCLUSION

According to directives 93/21/E.E.C, 2001/59/EC and 99/45/EC concerning the labelling and classification of dangerous substances and preparations, the item under investigation could be classified as follows:

LD50

Classification

Symbol

Indication of danger

LD50 <or=25 mg/kg

R28: very toxic if swallowed

T+

Very toxic

25 mg/kg < LD50 <or= 200mg/kg

R25: toxic if swallowed

T

Toxic

200 mg/kg < LD50 <or=2000 mg/kg

R22: harmful if swallowed

Xn

Harmful

LD50 > 2000 mg/kg

According to the Council Regulation No. 1272/2008, the item under investigation could be classified as follows:

LD50

Classification

Signal word

LD50 <or= 5 mg/kg

Category 1

“H300 Fatal if swallowed”

Danger

5 mg/kg < LD50 <or=50mg/kg

Category 2

“H300 Fatal if swallowed”

Danger

50 mg/kg < LD50 <or=300 mg/kg

Category 3

“H301 Toxic if swallowed”

Danger

300 mg/kg < LD50 £ 2000 mg/kg

Category 4

“H302 Harmful if swallowed”

Warning

LD50 > 2000 mg/kg

Price

Turnaround

4 weeks

€ : < 1500 € €€ : between 1500 and 4000 € €€€ : between 4000 and 20000 € €€€€ : > 20000 €
We call you back