Registration Dossier

Administrative data

Description of key information

Most repeated dose studies carried out have used inhalation, this is the most relevant route of exposure due to the fibrous nature of the material, no unusual ill effects were reported in any of the studies. A reproductive toxicity screening study (OECD 421) was carried out using this material administered orally, again no toxic effects were seen. 

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
250 mg/kg bw/day
Study duration:
subacute
Species:
rat

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEC
30 mg/m³
Study duration:
chronic
Species:
rat

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEC
30 mg/m³
Study duration:
chronic
Species:
rat

Additional information

The NOAEC reported for inhalation above is in mg/m3 but this is inappropriate for fibres where the concentration should be given in f/ml (specifying size characteristics), for this study the NOAEC should be reported as 174 WHO f/ml ±72 and 47 fibres >20µm/ml ±23.

Only physiological changes typical of the dust loading were seen, no pathological endpoints could be distinguished.


Repeated dose toxicity: via oral route - systemic effects (target organ) urogenital: ovaries; urogenital: testes

Repeated dose toxicity: inhalation - systemic effects (target organ) respiratory: lung

Justification for classification or non-classification

No abnormal effects observed in any long term inhalation study or shorter term oral study.