Registration Dossier

Administrative data

Description of key information

Acute toxicity of zinc bis(dibutyldithiocarbamate) (ZDBC) by oral and dermal exposure routes is low. Several acute oral toxicity studies give oral LD50 value over 5000 mg/kg bw for rats, while two acute dermal toxicity studies with rabbits give LD50 > 2000 mg/kg bw/day. No data on acute inhalation toxicity were available; however, in accordance with REACH Annex VIII, the study does not need to be conducted, as data on two other routes of exposure are available. 

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
5 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 000 mg/kg bw

Additional information

Four acute oral toxicity studies with zinc bis(dibutyldithiocarbamate) (ZDBC) were available for assessment, all reporting LD50 values well above 2000 mg/kg bw. Out of these studies, the most recent one (Monsanto Company, 1982a), performed under GLP, was chosen as a key study. Five Sprague-Dawley rats of each sex were administered a single oral dose of 5000 mg/kg bw of the test substance as a 434 mg/ml suspension in corn oil. No mortalities occurred and no abnormal findings were noted at necropsy. Diarrhoea occurred in three males and five female rats on the day of dosing, but this effect was probably induced by the corn oil used as the dosing vehicle.

Two acute dermal toxicity studies with rabbits were available for assessment, one with very limited reporting. Respectively, the other one, more recent GLP-compliant study (Monsanto Company, 1982b) was chosen as a key study. The test material moistured with physiological saline was administered to abraded skin of a dorsal surface of five New Zealand White rabbits of each sex in the amount of 2000 mg/kg bw under occlusive conditions. After 24 hours the patch was removed, the excessive test material wiped off, and the animals were observed for 14 days and necropsied afterwards. There were no mortalities. Erytherna was observed in the exposed area of three male animals and one female rabbit on the first day after exposure. No other clinical abnormalities were noted. At necropsy, pale renal coloration was observed in one male animal, but this was not considered to be related to exposure to the test material. No abnormalities were observed in the remaining nine rabbits.

No data on acute inhalation toxicity of zinc bis(dibutyldithiocarbamate) were available. However, in accordance with REACH Annex VIII, the study does not need to be conducted, as the data on two other routes of exposure are available.

Justification for classification or non-classification

Based on the acute oral LD50 of > 5000 mg/kg and the acute dermal LD50 of > 2000 mg/kg, ZDBC should not be classified as hazardous to health after acute exposure, according to the EU Directive 67/548/EEC and EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.