Potassium tetrafluoroborate

Endpoint summary

Description of key information

A LD50 greater than 2000 mg NaBF4/kg bw (equivalent to 2294 mg KBF4) was observed in the acute oral toxicity study and a LD50 of 5300 mg KBF4/m3 bw  was observed in the inhalation toxicity study.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

GLP-compliant guideline study, klimisch 1

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

5 300 mg/m³ air

Quality of whole database:

GLP-compliant guideline study, klimisch 1

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

No studies on the acute oral toxicity of potassium tetrafluoroborate are available. However, according to Article 13 of the REACH legislation, in case no appropriate animal studies are available for assessment, information should be generated whenever possible by means other than vertebrate animal tests, i.e. applying alternative methods such as in vitro tests, QSARs, grouping and read-across. One GLP-compliant OECD Guideline 401 study with rats (Safepharm Laboratories Limited, 1992a) is available for a structural analogue of potassium tetrafluoroborate, sodium tetrafluoroborate. A group of 5 male and 5 female rats was administered a single dose of 2000 mg/kg bw in water by gavage. Animals were observed for 14 days and necropsied. There were no deaths or clinical signs of toxicity. All animals gained weight during the study. No pathological findings were revealed at necropsy. Based on the results of the study, the LD50 was above 2000 mg/kg bw. Applying a correction for molecular weight (2/109.79*125.91), a NOAEL of 2294 mg/kg bw/day can be derived for KBF4.

One GLP-compliant acute inhalation study according to OECD Guideline 436 is available for potassium tetrafluoroborate (TNO Triskelion BV, 2012). In this study 3 male and 3 female were submitted to a 4 -hour nose only exposure to an analytical concentration of 5.3 ± 0.7 g/m3 potassium tetrafluoroborate. Animals were observed for 14 days before sacrifice. During the second half of the exposure, all animals showed a slightly decreased breathing rate. No clinical abnormalities were observed approximately one hour after exposure; two hours after exposure soiled fur was seen in two females, one of which also demonstrated lethargic behaviour. One day after exposure, all treatment-related abnormalities had disappeared. After an initial loss of body weight upon exposure normal body weight development was observed 3 days (five animals) and 7 days (one animal) after exposure. No deaths occurred. Macroscopic abnormalities at necropsy were limited to petechiae in single lung lobes of three animals and pale lungs in two other animals. Although it cannot be excluded that these findings were related to the exposure, the minor macroscopic abnormalities in the lungs may well have been part of common background pathology. Based on these findings, the 4-hour LC50 in rats was determined at >5.3 g/m3.

Justification for classification or non-classification

Based on the results of an oral and an inhalation acute toxicity study, the substance does not need to be classified according to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.