Disodium tetrachloropalladate

Endpoint summary

Description of key information

An acute oral LD50 value of between 500 and 2000 mg/kg bw was determined for disodium tetrachloropalladate in male and female rats (Middleton and Husband, 1978).

No relevant acute inhalation or dermal toxicity data were identified.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data (report date is March 1978)

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Early study, pre-GLP, but scientifically acceptable

Qualifier:

no guideline followed

Principles of method if other than guideline:

Standard acute method, to assess the acute oral toxicity of the test

GLP compliance:

no

Remarks:

(prior to GLP)

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Olac (1976) Ltd
Shaws Farm
Blackthorn
Bicester
Oxon
UK
- Age at study initiation: no data
- Weight at study initiation: males mean 215 g; females mean 180 g
- Fasting period before study: overnight
- Housing: polypropylene cages
- Diet (e.g. ad libitum): conventional; ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): “thermostatically controlled”
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): “controlled”

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 50 mg/ml
- Amount of vehicle (if gavage): 10 ml/kg bw
- Justification for choice of vehicle: no data
- Lot/batch no. (if required):
- Purity: water for injection

MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg bw

DOSAGE PREPARATION (if unusual):

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose:

Doses:

500 mg/kg bw (main study)
25, 50, 200, 500 and 2000 mg/kg bw (range-finding study)

No. of animals per sex per dose:

5/sex (main study)
1/sex/dose (range-finding study)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: at 4 hr, then daily. Weighed prior to dosing.
- Necropsy of survivors performed: no
- Other examinations performed: none

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 500 - < 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: CL not determined

Mortality:

At 2000 mg/kg bw both animals died; the female within 24 h and the male after 6 days. All animals dosed at 500 mg/kg bw survived the observation period.

Clinical signs:

other: No overt signs of toxicity were observed in animals treated at 500 mg/kg bw. Symptoms occurring before death in the two animals dosed at 2000 mg/kg bw are not reported.

Gross pathology:

There is no indication that gross pathology was examined

Other findings:

- Other observations: none

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

An acute oral LD50 value of between 500 and 2000 mg/kg bw was determined for disodium tetrachloropalladate in male and female rats.

Executive summary:

In an early pre-GLP study, disodium tetrachloropalladate was assessed for acute oral toxicity after single gavage administration in rats. The test substance, available as a brown powder, was given as an aqueous solution at doses of 25-2000 mg/kg bw to one rat of each sex in a range-finding study. A dose of 500 mg/kg bw was administered to groups of five male and female rats in the main study. Body weights were not recorded, except prior to dosing.

 

Both animals died after exposure to 2000 mg/kg bw, the female within 24 hr and the male after 6 days. No clinical signs were reported for either the deceased animals or the rats dosed at 25-500 mg/kg bw which survived the observation period.

 

In the main study in which animals were exposed to 500 mg/kg bw, all survived the 14-day observation period. There were no overt signs of toxicity at this dose level. Necropsies were not performed.

 

An acute oral LD50 value of between 500 and 2000 mg/kg bw was determined for disodium tetrachloropalladate in male and female rats. Based on the results of this acute oral rat study, disodium tetrachloropalladate should be classified for acute oral toxicity (category 4) according to EU CLP criteria (EC 1272/2008).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

discriminating dose

Value:

500 mg/kg bw

Quality of whole database:

Overall, good-quality database which meets REACH Standard Information Requirements.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

No relevant acute toxicity human data were identified.

 

In an early pre-GLP study, disodium tetrachloropalladate was assessed for acute oral toxicity after single gavage administration in rats. The test substance, available as a brown powder, was given as an aqueous solution at substance doses of 25-2000 mg/kg bw to one rat of each sex in a range-finding study. A dose of 500 mg/kg bw was administered to groups of five male and female rats in the main study. Body weights were not recorded, except prior to dosing. Both animals died after exposure to 2000 mg/kg bw, the female within 24 hr and the male after 6 days. No other clinical signs were reported for either the deceased animals or the rats dosed at 25-500 mg/kg bw that survived the observation period. In the main study in which animals were exposed to 500 mg/kg bw, all survived the 14-day observation period. There were no overt signs of toxicity at this dose level. Necropsies were not performed. An acute oral LD50 value of between 500 and 2000 mg/kg bw was determined for disodium tetrachloropalladate in male and female rats (Middleton and Husband, 1978). Based on the results of this acute oral rat study, disodium tetrachloropalladate should be classified for acute oral toxicity (category 4) according to EU CLP criteria (EC 1272/2008).

 

No relevant acute inhalation toxicity data were identified. However, the compound is not expected to reach the lungs in appreciable quantities (based on respiratory tract deposition modelling data with various palladium compounds). Thus, inhalation will not be a significant route of exposure. Similarly, no acute dermal toxicity data were identified. However, skin contact during production and/or use is expected to be negligible.

Justification for selection of acute toxicity – oral endpoint
Early pre-GLP study, but appears scientifically acceptable, and the only acute oral toxicity study available

Justification for selection of acute toxicity – dermal endpoint
OECD guideline study, to GLP, and the only acute dermal toxicity study available

Justification for classification or non-classification

Based on the results of the available acute oral rat study, disodium tetrachloropalladate should be classified for acute oral toxicity (category 4) according to EU CLP criteria (EC 1272/2008).

 

No clear evidence of specific target organ toxicity was noted. As such, classification for STOT-SE is not considered appropriate.