3,3'-[(2-chloro-5-methyl-p-phenylene)bis[imino(1-acetyl-2-oxoethylene)azo]]bis[4-chloro-N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]benzamide]

Endpoint summary

Description of key information

Oral: LD50 > 2000 mg/kg bw/day, OECD 401

Dermal: No data available. LD50 > 5000 mg/kg bw/day for CAS 5580-57-4 and CAS 5280-80-8

Inhalative (dust): LC50 (4h, rat) > 1.7 mg/L air (highest concentration possible), similar to OECD 403; read acorss with CAS 5580-57-4

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

7 750 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating conc.

Value:

1 700 mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

5 000 mg/kg bw

Additional information

There are reliable studies available to assess the acute oral and inhalation toxicity of the test substance. The studies were performed in 1983, 1973 and 1976 when characterization of powders in regard to particles with a size of < 100 nm was not routinely performed. Doses applied exceeded the maximum doses later prescribed in OECD testing guidelines. Retrospective analysis did not allow any conclusion on whether the test material was a a nanomaterial or not. However, organic pigments are all powders that often have a nanosize fraction. They consistently show absence of a hazard if tested up to the limit dose in studies with oral and dermal dosing (Stratmann, et al. Indicators for lack of systemic availability of organic pigments, https://doi.org/10.1016/j.yrtph.2020.104719, Regulatory Toxicology and Pharmacology Volume 115, August 2020, 104719). The publication lists 113 and 35 pigments tested for acute oral and dermal toxicity, respectively and in none of the studies, treatment-related morbidities were observed. Therefore, the available experimental data is considered adequate to assess the hazard of the pigment both in the bulk and in the nano form.  

Oral:

Two studies on acute toxicity after oral application are available for the test substance. In an acute oral toxicity study groups of 20 Tif. RAI rats (10/sex) were given a single dose of the test substance suspended in 30% carboxymethyl-cellulose at doses of 6000 and 7750 mg/kg bw and were observed for 7 days. Within 2 hours after treatment the rats of both dosage groups showed sedation, dyspnoea, exophthalmus, curved position and ruffled fur. The animals recovered within 4 to 6 days. No substance related gross organ changes were seen. The observed LD50 was greater than 7750 mg/kg bw (BASF, 1973).

In a supporting acute oral toxicity study, rats were exposed to a limit concentration of 5000 mg/kg bw of the test substance in arachis oil. Under the conditions of this study an LD50 above 5000 mg/kg bw were observed (Ciba-Geigy Ltd., 1983).

Both studies reveal a very low acute oral toxicity of the pigment with LD50 values in rats above 2000 mg/kg bw, the upper limit for classification.

 

Inhalation:

In an acute inhalation toxicity study (similar to OECD 403, Ciba-Geigy Ltd., 1976), groups of Tif:RAIf rats (9/sex) were exposed to dust of the test substance (CAS 5580-57-4) for 4 hours and observed for 14 days. No mortality occurred during 14 day observation. At concentrations of 1700 mg/m³ air at the 4 hour exposure the animals showed no toxic symptoms. At autopsy, no deviations from normal morphology were found in all animals. 1700 mg/m³ air was the highest possible concentration. That leads to an LC50 greater than 1700 mg/m³ air at 4 hour exposure. As no lethal effects occurred at the maximum technically feasible concentration it is concluded that the members of the 'yellow disazo condensation pigments' have not to be classified for acute toxicity after inhalation exposure.

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No 1272/2008
The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. Based on available data on acute toxicity, the test item is not classified according to Regulation (EC) No 1272/2008 (CLP), as amended for the tenth time in Regulation (EU) No 2017/776.