5-Isothiazolecarboxamide, 3,4-dichloro-N-(2-cyanophenyl)-

Endpoint summary

Description of key information

oral: LD50 rat > 2000 mg/kg (limit test)
dermal: LD50 rat > 2000 mg/kg (limit test)
inhalation: LC50 rat > 5.0 mg/L (limit test, 4h exposure, aerosol, nominal value)

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VII, 8.5, of Regulation (EC) No 1907/2006.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

5 000 mg/m³ air

Quality of whole database:

The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VIII, 8.5, of Regulation (EC) No 1907/2006.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VIII, 8.5, of Regulation (EC) No 1907/2006.

Additional information

The acute oral toxicity of the test substance was assessed according to OECD 423 in a limit test with administration of a single dose of 2000 mg/kg bw to female rats (Schüngel, 2005). No mortality occurred during the course of the study. No clinical signs were observed and there was no effect on body weight or body weight gain, nor were there macroscopically visible changes at necropsy. Therefore, the oral LD50 is considered to be higher than 2000 mg/kg bw.

Acute toxicity by inhalation was assessed in a limit test (Deguchi, 2007) according to OECD 403, in which rats were exposed to an aerosol of the test substance for 4 hours at 5000 mg/m3 (5 mg/L). The actual aerial concentration chemically was 4.75 mg/L and actual aerial concentration gravimetrically 4.6 mg/L. No mortality occurred during the course of the study. 2-3 animals in each group had wet patches on their fur (primarily back abdomen region) during the first hour immediately following exposure. This is considered to be a result of the restraint procedure, and not an effect of the substance. Although there was no significant difference in body weight values, significantly lower body weight gain was observed in the female exposure group after 14 days of exposure. There were no unusual findings of the gross pathology. Based on these results, the inhalation LC50 is set as higher than 5 mg/L.

The acute dermal toxicity was tested in male/female rats with a limit test according to OECD 402 (Keiko, 2006). A single dose of 2000 mg/kg bw was applied to the skin under occlusive dressing for 24 hours. No mortality occurred during the course of the study and no clinical signs were observed. There was no effect on body weight or body weight gain, and there were no treatment-related macroscopic changes at necropsy. Therefore, the dermal LD50 is considered to be higher than 2000 mg/kg bw.

The test substance-related findings were comparable for all routes of application during the acute toxicity studies, indicating that the test substance has a very low potential for acute toxicity.

Justification for selection of acute toxicity – oral endpoint
The reliable GLP compliant OECD Guideline study was chosen.

Justification for selection of acute toxicity – inhalation endpoint
The reliable GLP compliant OECD Guideline study was chosen.

Justification for selection of acute toxicity – dermal endpoint
The reliable GLP compliant OECD Guideline study was chosen.

Justification for classification or non-classification

The available data are conclusive but not sufficient for classification according to the criteria of DSD (67/548/EEC) and CLP (1272/2008/EC).