Hydroxido potassium zirconium carbonate, where there are 0, 1 or 2 hydroxide groups and 2, 3 or 4 potassium atoms and 2, 3 or 4 carbonate groups.

Endpoint summary

Description of key information

The acute oral toxicity was determined to be LD50 > 2000 mg/kg bw in rats (Cuthbert 1992a).
The acute dermal toxicity was detemined to be LD50 > 2000 mg/kg bw in rats and was perfomed with the read-across substance ammonium zirconium carbonate (Bradshaw, 2009).

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Quality of whole database:

The study was therefore assigned a reliability score of 1 according to the principles for assessing data quality according to Klimisch (1997).

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

Quality of whole database:

The key study was assigned a reliability score of 2 as there is sufficient information to assess the accuracy and reliability of the data. The supporting study has been assigned a reliability score of 4. Both studies were scored according to the principles for assessing data quality according to Klimisch (1997).

Additional information

Oral The acute oral toxicity potential of the test material, potassium zirconium carbonate, was investigated in rats. The vehicle for the dosing solution was distilled water. Two dose levels were investigated, 5000 and 2000 mg/kg. At a dose level of 5000 mg/kg there were 5 deaths, 2 males and 3 females. Clinical signs, noted 10 minutes - 7 hours after dosing, included ataxia, subdued behaviour, increased salivation, hunched appearance, laboured breathing, hyperventilation, red ocular discharge and prostration. Necropsy findings, noted in premature decedents only, were limited to a distended stomach filled with clear fluid. At a dose level of 2000 mg/kg there were no deaths. Clinical signs, noted at 0.5 h after dosing, were limited to one male animal which showed increased salivation. No abnormalities were detected at necropsy. The Median Oral Lethal Dose (LD₅₀) of the test material in rats is > 2000 mg/kg. Dermal In order to assess the acute dermal toxicity of the test substance registered a study with the analogue substanceammonium zirconium carbonate (44.6% aqueous solution of AZC equivalent) wasevaluated.Please refer to point 5.2.1 above and to the document "KZC consolidated read-across report", as attached to Section 13 of the IUCLID, for a detailed justification for this proposed read-across.The acute dermal median lethal dose (LD₅₀) of ammonium zirconiumcarbonate in the Wistar strain rat was found to be greater than 2000 mg/kg bodyweight in an OECD 402 study, with no deaths and no signs of systemic toxicity at this dose level. Inhalation In accordance with column 2 of REACH Annex VIII, the acute inhalation study (as required in section 8.5.2) is not considered scientifically justified on the grounds that inhalation exposure is unlikely to occur. Oral and dermal exposure routes are considered adequate to address the acute toxicity of the substance.  

Justification for selection of acute toxicity – oral endpoint
Only one study was avaliable. The study was conducted according to GLP and performed to a high standard following OECD 401 and EU B.1 guidelines.

Justification for selection of acute toxicity – dermal endpoint
The key study (Bradshaw, 2009) was performed on a surrogate substance, ammonium zirconium carbonate, provided on the basis of read-across given the common ionic components, ZrO2. The study was conducted according to GLP and performed to a high standard following OECD 402 and EU B.3 guidelines.

The supporting information (Anonymous, 2012) has been provided on a second surrogate substance, potassium carbonate, provided on the basis of read-across. The acute dermal toxicity has been reported as part of a company material safety data sheet and thus information regarding the method adopted is not available.

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation 1272/2008, the test material does not require classification for acute toxicity. Acute oral and dermal LD50 values are both > 2000 mg/kg.