Disodium 4,4'-bis[(4-anilino-6-methoxy-1,3,5-triazin-2-yl)amino]stilbene-2,2'-disulphonate

Endpoint summary

Description of key information

LD20 = 3300 mg/kg bw

LD50 > 3300 mg/kg bw

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Additional information

The acute oral toxicity of the substance was assessed using a test sample with composition: 33 % OB 134, 38 % water and coupage as for the remaining. Based on information reported in study reports, the sample is liquid.

OB 134 was administered to rats (5 dose/sex) at doses of 4640, 7750, 9000 and 10000 mg/kg, causing death on 1 rat/sex only in the high dose group within 24 hours from dosing. A 14 -day observation period followed dosing.

Further studies were available and are summarised in the table below:

test material	composition	method	results	date
FAT 65006/E	33 % a.i., 38 % water, coupage	5 rabbit/sex/dose; 30 % concentration of formulation; 4640, 6000, 7750 mg/kg test material; 14-day observation period	LD0 = 7750 mg/kg LD0 = 2558 mg/kg (a.i.)	1976
Rylux PRS	70 - 80 % a.i, 20 - 30 % non coloured components	20 % suspension in olive oil, rats	LD20 = 15850 mg/kg LD20 = 11888 mg/kg (a.i.) LD50 > 15850 mg/kg	1980

The first study followed the same test procedure as the key study; however, physical state of test sample was solid. Few details on test procedure and results were available on the second study. Overall, available data indicated low toxicity of OB 134 by acute oral exposure.

A study on acute inhalation toxicity of OB 134 was also available. It was conducted as limit test: 10 rats were exposed to test substance for 4 hours in the inhalation chamber at concentration of 5 mg/l. In the 14 -day observation period, no treatment related deaths were reported; effects were found to be reversible and no macroscopic changes were noted at necropsy. Therefore, LC0 = 5 mg/l and no LC50 could be established.

Data on acute dermal toxicity to rats also available. No signs of intoxication were noted; rats were killed 14 days upon application and no macroscopic changes were detected in the organs.

Justification for classification or non-classification

According to the CLP Regulation (EC 1272/2008), substances can be allocated to one of four toxicity categories based on acute toxicity by oral, dermal or inhalation route according to numeric criteria. Acute toxicity values are expressed as (approximate) LD50 (oral, dermal) or LC50 (inhalation) values or as acute toxicity estimates (ATE).

 

The oral LD50 value was established to be greater than 2000 mg/kg bw, therefore the test substance is above the classification threshold for acute oral toxicity (Category 4: 300 < ATE ≤ 2000 mg/kg).

The dermal LD50 value was found to be above 5000 mg/kg bw, thus above the classification threshold for acute dermal toxicity (Category 4: 1000 < ATE ≤ 2000 mg/kg).

The inhalation LC50 value was found to be above 5 mg/l, thus above the classification threshold for acute inhalation toxicity of dust (Category 4: 1.0 < ATE ≤ 5.0 mg/l).