Strategy For Limiting Risks Human Health Draft of ... - ECHA - Europa

As can be seen from table 2.4 there is one dermal scenario at risk (scenario 3: use in other
industries). It has to be kept in mind though, that under the aspect of systemic toxicity the
critical exposure level for repeated dermal contact with cryolite is 1.3 mg/kg/day
(92 mg/person/day / 70 kg/person). If this would be kept, developmental risks would also be
diminished.
Combined exposure
24
Conclusion: iii
For risk assessment of combined exposure the internal level of fluoride corresponding to the
oral NOAEL is calculated as 19.3 mg F⎯ /kg/day (42 mg cryolite/kg/day x 0.85 x 0.54), taking
into account the oral absorption percentage and the fluoride content of cryolite. This is used as
starting point for combined risk assessment.
Similar adjustment factors as above for dermal and inhalation exposure are applied giving a
reference MOS of 50. The critical internal fluoride level results as 0.39 mg F⎯/kg/day
(19.3/50) with respect to developmental toxicity.
In comparison to inhalation and dermal risk assessment one additional scenario is identified to
be of concern because of combined exposure at both routes. However, from repeated dose
toxicity the reference dose for fluoride uptake at the workplace is derived as 0.07 mg
F⎯/kg/day or 5 mg F⎯/person/day. If this would be kept, developmental risks would also be
diminished.
Conclusion: iii