Registration Dossier

Administrative data

Description of key information

ORAL
Key study:- LD50 300 - < 500 mg/kg bw, rat (female) OECD 423, EU Method B.1 tris, Wolf (2006)
INHALATION
Key study:- LC50 = 6.8 mg/L (males); 2.1 mg/L (females), rat, OECD 403, EU Method B., Weniger (2006)

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
Value:
300 mg/kg bw
Quality of whole database:
The key study was assigned a reliability score of 1 according to the criteria of Klimisch (1997). Supporting information is available in the form of citations in peer reviewed handbooks; these data were assigned a reliability score of 2. Overall, the quality of the database is good.

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LC50
Value:
2 100 mg/m³
Quality of whole database:
The key study was assigned a relaibility score of 1 according to the criteria of Klimisch (1997). Overall, the quality of the database is good.

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

ORAL

The key study is a GLP compliant acute oral toxicity study conducted in accordance with OCED Guideline 423 and EU method B.1 tris, using the fixed dose procedure. During the study female rats were subject to an oral dose of 300 or 2000 mg/kg of the test material by oral gavage and then were observed for 14 days. All of the animals dosed at 2000 mg/kg bw died 2 to 4 hours ater dosing; animals dosed at 300 mg/kg bw survived until the end of the observation periof. No signs of ill-health were observed in animals dosed at 300 mg/kg bw; however gastrointestinal irritation was observed in animals dosed at 2000 mg/kg bw before their death. Under the conditions of the study the LD50 was determined to be > 300 - <500 mg/kg bw. Since the study was conducted to GLP and to standardised guidelines, it was assigned a reliability score of 1 according to the criteria of Klimisch.

 

Supporting information is available in the form of five references, cited in peer reviewed handbooks. In the first, the LD50 was reported as 1150 mg Ta/kg in rats. In the second the LD50 was reported to be 2500 mg/kg in an unspecified animal. In a third, the LD50 was determined to be 2500 mg/kg in rats dosed by gavage. In the fourth, the test material was reported to have an LD50 of 110 mg/kg, and in the fifth the LD50 was reported to be 2500 mg/kg. Since the supporting information is taken from handbooks which have been peer reviewed, the data were assigned a reliability score of 2.

 

Supporting information is also available on the read across substance KTaF7. Information on this substance, taken from a peer-reviewed handbook, cited the LD50 to be 2500 mg/kg in rats. Since the data relate to a read across substance they were assigned a reliability score of 4.

INHALATION

In a GLP compliant acute inhalation study, conducted in accordance with OCED Guideline 403 and EU method B.2, the acute inhalation toxicity of the substance was determined. Rats were exposed to three concentrations of the test material for a period of four hours. Under the conditions of the test, the test material caused local tissue destruction in the lungs when administered by inhalation to rats. This was followed by a decrease in oxygen exchange to an extent that became lethal in some cases. The LC50values were determined to be 6.8 mg/l (males), 2.1 mg/l (females) and 3.3 mg/l (males and females).

DERMAL

In accordance with Section 1 of Annex XI of Regulation (EC) No. 1907/2006 (REACH), it is considered justified to omit the acute dermal toxicity study required under information point 8.5.3 of Annex VII on the basis of exposure considerations.

The physical state, high molecular weight and low water solubility, indicate very low potential for dermal absorption.

As dermal absorption cannot be greater than oral absorption, and gastrointestinal absorption of Ta salts is relatively low, no dermal absorption of the registered substance is expected to occur.


Justification for selection of acute toxicity – oral endpoint
A GLP study conducted in accordance with standardised guidelines, performed on the typical species for this endpoint and with a high level of reporting.

Justification for selection of acute toxicity – inhalation endpoint
Only one study is available.

Justification for classification or non-classification

In line with Directive 67/548/EEC, the substance is considered to be classified as ‘Harmful’ with the associated risk phrases “R22: Harmful if swallowed” and “R20: Harmful if inhaled”. Under Regulation (EC) No. 1272/2008, the substance is classified as 'Acute Toxicity 4' with the associated hazard phrases "H302: Harmful if swallowed" and "H332: Harmful if inhaled".

                                                    

In line with Directive 67/548/EEC and Regulation (EC) No. 1272/2008, the substance is considered to be unclassified for dermal toxicity.