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16 Conclusion: ii Eyes Information on eye irritation indicates that cryolite may have a certain potential for eye irritation, but due to the low quality of the available data a final assessment is not possible. A precautionary classification with R36 is proposed. Due to that insufficient data base for C&L decisions conclusion (i) on hold applies. Conclusion: i (on hold) Respiratory tract From human examinations no local effects on the respiratory tract were described. Also in the rat LC50-study no clinical signs of respiratory tract irritation were observed at 1,330 mg/m³. However, in animal studies with longer duration (14-day inhalation study with 5.1, 14, 60, 130, 470 mg/m 3 of particulate test substance) various inflammatory lesions were observed which concerned the alveolar parenchyma, the bronchiolar –alveolar junctions and the lumen of the large bronchioles slight bronchiolar hyperplasia. Also after chronic inhalation of Cryolite, rats showed lung changes. With respect to short-term single exposure up to 10 mg/m³ (highest exposure value, resulting from scenario 3), severe airway damage is not anticipated and no concern is expressed. For the assessment of local effects after repeated contact see the chapter below. Sensitisation Conclusion: ii Skin In a fully guideline-compliant Magnusson Kligman Test a skin sensitising potential of cryolite could not be demonstrated. Also monitoring data at the workplace do not indicate specific skin reactions of workers to cryolite. There is no concern with respect to skin sensitisation of cryolite. Conclusion: ii Respiratory tract No information on the sensitising potential of the substance at the respiratory tract is available. For the time being a valid study to investigate respiratory sensitisation in experimental animals cannot be recommended. Some cases of bronchial asthma have been observed at workplaces with mixed exposure to several chemicals, which however, did not give notice of a specific sensitising potential of cryolite. These effects are dealt with in the RAR-chapter 4.1.3.2.2, irritation and corrosivity, respiratory tract. On the background of these data cryolite is not suspected to be a potent respiratory sensitiser in humans. There is no concern with respect to respiratory sensitisation at the workplace. Conclusion: ii
Repeated dose toxicity Local effects Inhalation exposure For prolonged inhalation exposure of workers to cryolite, data on possible health effects are available from different sources such as mining and processing of natural cryolite, production of syntethic cryolite and manufacturing of aluminium. There has been no indication for cryolite specific chronic respiratory effects in humans although specific examinations have been made (x-ray photography, pulmonary function tests, questionaires concerning incidences of acute pulmonary symptoms). Exposure in some cases has been rather high and longlasting, causing severe skeletal fluorosis. In a well-conducted 90-day inhalation study rats were exposed snout-only to particulate aerosols of cryolite in the concentration of 0, 0.21, 1.04, and 4.6 mg/m 3 . Alveolitis with interstitial thickening of alveolar duct walls and increased collagen in alveolar ducts occurred in the high dose group. At the intermediate dose of Cryolite, a proportion of rats had interstitial thickening of the alveolar duct walls. These effects might indicate of the start of a fibrotic process in the lung. At the low dose (0.21 mg/m 3 ) no effect was observed. For the risk assessment this NOAEC of 0.21 mg/m 3 is used as starting point concerning effects of cryolite after repeated inhalation. For the identification of the reference MOS the following aspects are taken into account: The human data give no indication for cryolite specific chronic respiratory effects. Therefore, the NOAEC gives a very precautious value for the evaluation of this endpoint. On that background it does not seem indicated to apply any additional assessment factors like inter- or intraspecies extrapolation or duration adjustment. On the other hand the NOAEC, based on a 90-day study, might make a duration factor of about 2 necessary, because a progression of effects in the lungs (thickening of alveolar ducts and increased collagen) cannot excluded. In summary for the reference MOS a value of about 2 is proposed; the critical exposure level calculates then to 0.1 mg/m 3 (0.2 mg/m 3 / 2). Table 2.2 shows, that all scenarios exceed the critical exposure level thus giving reason for concern. 17 Conclusion: iii
Page 1 and 2: TRISODIUM HEXAFLUOROALUMINATE (Cryo
Page 3 and 4: CONTENT 0 SUMMARY 5 1 BACKGROUND 7
Page 5 and 6: 0 Summary Trisodium hexafluoroalumi
Page 7 and 8: 1 Background In the framework of EU
Page 9 and 10: By-production in aluminium smelters
Page 11 and 12: Company Location(s) Alcoa Aviles Sp
Page 13 and 14: Table 2.1: Occupational exposure le
Page 15: Comparison of MOS and reference MOS
Page 19 and 20: was established at 0.5 mg/m 3 (6h/d
Page 21 and 22: Combined exposure For all exposure
Page 23 and 24: Developmental toxicity Cryolite was
Page 25 and 26: Table 2.4 Developmental toxicity, p
Page 27 and 28: Tables 2.6 (inhalation) and 2.7 (de
Page 29 and 30: Table 2.7: Ranking of health risks
Page 31 and 32: Respiratory tract Regarding the sen
Page 33 and 34: and the analog sodium fluoride (NTP
Page 35 and 36: 3 Current Risk Reduction Measures C
Page 37 and 38: Country OEL (mg/m 3 STEL ) (mg/m 3
Page 39 and 40: 4 Possible Further Risk Reduction M
Page 41 and 42: Scenario 2: Use of cryolite in the
Page 43 and 44: Technical and organisational measur
Page 45: 6 Further Risk Reduction Measures R

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