Potassium tetrafluoroaluminate

Endpoint summary

Description of key information

Based on the read-across from multiconstituent aluminium potassium fluoride, the substance is not considered to be irritating to the skin and respiratory tract, while it is considered to induce eye irritation.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

No skin and eye irritation studies are available on potassium tetrafluoroaluminate. However, Article 13 of the REACH legislation states that, 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. Data are available on a structural analogue, multiconstituent aluminium potassium fluoride. Multiconstituent aluminium potassium fluoride is a multi-constituent substance containing ca. 70% of KAlF₄and ca. 30% of higher homological penta- and hexafluoroaluminic acids, K₂AlF₅and K₃AlF₆. The presence of these higher homological salts is, however, not expected to alter significantly the physico-chemical and toxicological properties of multiconstituent aluminium potassium fluoride in comparison to potassium tetrafluoroaluminate.

Skin irritation Three skin irritation studies are available on multiconstituent aluminium potassium fluoride (Hazelton Laboratories, 1985g,h,i). Different multiconstituent aluminium potassium fluoride batches were tested: multiconstituent aluminium potassium fluoride 100 FLUX (AT-1 -KC), multiconstituent aluminium potassium fluoride NK FLUX (AT-2 -NK) and multiconstituent aluminium potassium fluoride NK FLUX (AT-3 -NL). The test substance (moistened with 0.9% saline) was applied to the skin of three male and three female rabbits on two sites (one abraded, one unabraded) for 24 hours under occlusion. Thirty minutes after removal and at 72 hours, dermal irritation was assessed (according to the Draize score). The Primary Dermal Irritation Indices (PDII) were 0.2, 0.8 and 0.2 at 24 hours and 0, 0 and 0.1 at 72 hours for multiconstituent aluminium potassium fluoride 100 FLUX (AT-1 -KC), multiconstituent aluminium potassium fluoride NK FLUX (AT-2 -NK) and multiconstituent aluminium potassium fluoride NK FLUX (AT-3 -NL), respectively. Furthermore, the primary skin irritation scores (erythema and edema) for both intact and abraded skin did not indicate that aluminium potassium fluoride is irritating to the skin. Based on these results, potassium tetrafluoroaluminate is also not considered to be irritating to the skin.

Eye irritation A GLP compliant guideline study is available on multiconstituent aluminium potassium fluoride (RCC Ltd, 2000). The test substance was applied by instillation of 0.1 g into one eye of three NZW rabbits (1 male and 2 females) with the contralateral eye serving as the untreated control. The eyes of the rabbits remained unflushed. The eye reactions (mean values from 24 to 72 hours) consisted of grade 1.00 corneal opacity, grade 0.00 iris lesions, grade 2.00 redness of the conjunctivae and grade 1.33 chemosis of the conjunctivae. Diffuse corneal opacity was seen in all animals at the 1-hour examination and persisted through 72 hours before disappearing at 7 days (one animal), 10 days (one animal) or 21 days (one animal). Slight reduced light reflex of the iris was noted in one animal at the 1-hour examination. Hyperemic blood vessels of the conjunctivae and nictitating membrane were observed in all animals 1 hour after treatment and increased in severity through 72 hours before diminishing to clear by day 10 (one animal), 14 (one animal) or 17 (one animal). Obvious swelling of the conjunctivae and nictitating membrane with partial eversion of lids or with lids about half-closed was observed in all animals at the 1-hour reading before diminishing by day 7 (one animal), 10 (one animal) or 14 (one animal).

A red ring of blood vessels was observed in all animals above the iris at the 7-day reading and persisted in two animals at the 10-day reading before disappearing in only one animal 14 days after treatment.

The sclera was not visible in all animals at 1 hour due to the swelling. A slightly reddened sclera was observed in all animals at the 24-hour reading and increased in severity in one animal at the 48-hour reading whereas the sclera was not visible in the two other animals due to the mucous production in the treated eye. When the sclera of one animal was not visible, a moderately reddened sclera was seen in the two other animals at 72 hours. Slightly to markedly reddened sclera was observed in all animals from 7 to 17 days after treatment and still persisting on test day 21 in two animals. No staining of the treated eyes by the test item was observed. No corrosion was observed at any of the measuring intervals. All eye reactions were not clear 21 days after treatment.

Regarding the interpretation of the results, it should be noted that 0.1 g was applied instead of 0.1 ml. Furthermore, the eyes were not rinsed after 1 hour. Therefore the conditions under which this test was performed are considered ‘worst-case’ compared to the prescribed conditions in the OECD guideline. Based on the eye irritation scores for the period 24-72 hours, it is concluded that multiconstituent aluminium potassium fluoride is irritating to the eyes.

In the other eye irritation study (Hazelton Laboratories, 1985j), three male and three female rabbits received 0.07 g (0.1 ml) test material on the everted lower eyelid, with the contralateral eye serving as the untreated control. The eyes of the rabbits remained unflushed. Occular irritation was assessed (according to the Draize score) after 24, 48, 72 and 96 hours and 7, 14 and 21 days. The following primary eye irritation scores were reported: 24 hours: 23.8; 48 hours: 19.2; 72 hours: 19.8; 96 hours: 15.7; 7 days: 13.8; 14 days: 7; 21 days: 6.3. White necrotic areas on the conjunctivae were seen in two animals at 24, 48, 72 and 96 hours and 7 days. Pannus was observed in two animals at 7, 14 and 21 days. One animal exhibited corneal neovascularization at day 21. The mean (24, 48, 72 hrs) cornea score and iris score were 1.22 and 0.55, respectively (both not fully reversible within 21 days). No reliable conjunctivae and chemosis scoring was possible due to white necrotic areas.

 

The study perfomed by RCC Ltd. (2009) is considered the key study. The study performed by Hazalton Laboratories (1985j) is considered less reliable (no detailed test substance description of composition, not conducted under GLP, old draize method principle etc.). Based on the results of the key study, it is concluded that the multiconstituent aluminium potassium fluoride is irritating to the eyes.

Based on these results, potassium tetrafluoroaluminate is also considered to be irritating to eyes.

Respiratory tract irritation The available inhalation toxicity studies on multiconstituent aluminium potassium fluoride (acute toxicity, sensory irritation, respiratory tract sensitisation and repeated dose toxicity by inhalation) do not trigger classification for respiratory tract irritation. Based on this, potassium tetrafluoroaluminate is also considered to be not a respiratory irritant.

Effects on eye irritation: irritating

Justification for classification or non-classification

Based on the read-across with multiconstituent aluminium potassium fluoride, potassium tetrafluoroaluminate does not need to be classified for skin and respiratory tract irritation. Based on the results of the available eye irritation studies, in accordance to Directive 67/548/EEC and EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008, the substance has to be classified as Xi; R36 and Cat. 2; H319, respectively.