Registration Dossier

Administrative data

Description of key information

No reliable studies were available however ZrCl4 may be inhaled and was classified as skin corrosive. Therefore ZrCl4 is considered as corrosive to the respiratory tract.

Key value for chemical safety assessment

Additional information

Two studies indicate a LD50 value. For one study, only the result is available with no further information (reliability 4) and the other study of Delongeas et al. (1983) has a reliability of 3 because zirconium tetrachloride was administered via the drinking water. Under this condition, it was the degradation products (zirconium tetrachloride is unstable in contact with water and decomposes into ZrOCl2 and hydrogen chloride) which were ingested. The observed effects, after this exposure, were associated to hydrogen chloride (intestinal necrosis and pulmonary necrosis) and confirmed this conclusion.

In conclusion, there is no valid study for this endpoint. However, a new study has not to be conducted due to ZrCl4 hydrolytical unstability and the properties of one of its degradation products (HCl) which are corrosive (this substance is classified as R35 under the CLP regulation 1272/2008 - Annex VI Table 3.1). Moreover, ZrOCl2 is also unstable in contact with water and finally decomposes into ZrO2 (no hazardous substance) and HCl.

Justification for classification or non-classification

No studies were available. However zirconium tetrachloride may be inhaled and was classified as skin corrosive. In accordance with the CLP regulation 1272/2008, in addition to classification for skin corrosion, the supplement hazard information EUH071 (corrosive to the respiratory tract) was proposed.