Registration Dossier

Diss Factsheets

Administrative data

Link to relevant study record(s)

Description of key information

Key value for chemical safety assessment

Additional information

There are no data on toxicokinetics of boron trifluoride.

Measurement of fluoride ion production over a range of pH values (1.2 to 9) indicated a hydrolytic half-life time of less than 30 minutes for boron trifluoride. Subsequent analysis of boric acid by titration confirmed the rapidity of the reaction. Consequently, when no data is available, the risk associated to dehydrated boron trifluoride when release into water can be assessed based upon the hazards of its breakdown products in water: boric acid and fluoboric acid.

With regards to boric acid,the preliminary study showed that at each of pH 1.2, 4, 7 and 9 and 50±0.5ºC, less than 10% hydrolysis had occurred after 5 days, equivalent to a half-life of greater than 1 year under environmental conditions (25°C). Thus Boric acid was determined to be hydrolytically stable under acidic, neutral and basic conditions.

With regards to tetrafluoroborate, it is apparent thattetrafluoroborate hydrolyses under environmental conditions, forming boric acid and, predominantly, partially hydrolysed fluoroborate species (i.efluorine and hydronium ions). HF is not expected at significant amounts as it occurs in the systemic circulation only as free ionic or as organically bound fluoride.

Boric acid is readily absorbed orally and by inhalation; no dermal absorption (< 0.5%) occurred. It is then rapidly distributed through body water and is not metabolised.