Silicic acid (H2Si2O5), barium salt (1:1), lead-doped

Endpoint summary

Description of key information

Silicic acid (H2Si2O5), barium salt (1:1), lead-doped was administered by daily oral gavage to male and female Wistar Han rats at dose levels of 30, 100 and 300 mg/kg/day. Males were exposed for 2 weeks prior to mating, during mating, and up to termination (for a total of 28 days). The females were exposed for 2 weeks prior to mating, during mating, during post-mating, and at least 4 days of lactation (for 41-47 days). Based on mortality and clinical signs the parental NOAEL was determined to be 30 mg/kg bw/day.

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion

Dose descriptor:

NOAEL

30 mg/kg bw/day

Study duration:

subacute

Species:

rat

Additional information

Silicic acid (H2Si2O5), barium salt (1:1), lead-doped was administered by daily oral gavage to male and female Wistar Han rats at dose levels of 30, 100 and 300 mg/kg/day. Males were exposed for 2 weeks prior to mating, during mating, and up to termination (for a total of 28 days). The females were exposed for 2 weeks prior to mating, during mating, during post-mating, and at least 4 days of lactation (for 41-47 days).

Parental results:

A single male and six females at 300 mg/kg/day and a single female at 100 mg/kg/day were either found dead or euthanized in extremis. Females were mostly found dead or sacrificed towards the end of their pregnancy period. Among most of these animals clinical signs indicative of ill-health were noted. A cause of death could however not be established based on in-life data, macroscopy or histopathology. The single death case at 100 mg/kg/day was also considered to be related to treatment since the time of death (towards end of pregnancy) and the nature of clinical signs observed prior to its death corresponded to that noted among most deaths at 300 mg/kg/day.

Any macroscopic abnormalities observed among surviving animals at 300 mg/kg/day were not associated with treatment-related histopathological changes and were therefore considered to be of no toxicological relevance.

Apart from mortality and associated clinical signs at 100 and 300 mg/kg/day, no toxicologically-relevant changes were recorded for any of the parameters (functional observations, body weight, food consumption, clinical laboratory investigations, organ weights, macroscopy and microscopic examination) investigated in this study, including at 30 mg/kg/day.

Parental NOAEL: 30 mg/kg/day

Justification for classification or non-classification

Based on the available data, Silicic acid (H2Si2O5), barium salt (1:1), lead-doped, does not need to be classified for repeated dose toxicity according to Directive 67/548/EC or the CLP Regulation.