CAS Nos. 15096-52-3 and 13775-53-6

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Adverse Effects

ACTIVITY: Insecticide (Fluorine, Inorganic)

(Aluminum sodium fluoride)

Molecular formula: Al-F6.3Na
CAS No. 15096-52-3
Aluminate(3-), hexafluoro-, trisodium, (OC-6-11)-
(Aluminum sodium fluoride)

Molecular formula: Al-F6.3Na
CAS No. 13775-53-6

• The cryolite referred to by US EPA for pesticide use is CAS No. 15096-52-3. Both of the above structures are the same. The only difference is that there are two CAS numbers.

• On March 4, 2004, Solvay Fluorides (a subsidiary of Solvay Chemicals, Inc.) submitted a report to US EPA titled: Solvay Fluorides - TSCA Section 8(e) - Sodium Hexafluoroaluminate (CAS No. 13775-54-6 - 90 Day Repeat Dose Inhalation Study in Rats (snout only exposure).


Adverse Effects:

Body Weight Decrease
Anorexia, Wasting

Regulatory Information
(only comprehensive for the US)
US EPA Registered: Yes
US EPA PC Code: 075101
California Chemical Code 173
US Tolerances: CFR 180.145
CFR 185.3375
FDA LMS Code: 040
Registered use in
(includes only a limited list of countries)

US Maximum Residue Levels permitted in food commodities

Apricot, Blackberry, Blueberry (huckleberry) Boysenberry, Broccoli, Brussels Sprout, Cabbage, Cauliflower, Citrus fruit, Collards, Cranberry, Dewberry, Eggplant, Fruit (citrus), Grape, Kale, Kiwifruit, Kohlrabi, Lettuce, Loganberry, Melon, Nectarine, Peach, Pepper, Plum (prune, fresh), Pumpkin, Raspberry, Squash (summer & winter), Strawberry, Tomato, Youngberry 

Other Information
Molecular Formula: Al F6 Na3
Manufacturers: Gowan
Other Names: Sodium aluminum fluoride
Cryolite synthetic
Sodium fluoaluminate
Sodium aluminofluoride
Of special interest:
PAN Data
Material Safety Data Sheets & Labels
Contaminated site - Bensalem Redevelopment L.P. (formerly Elf Atochem North America), Bensalem Township, Bucks County, Pennsylvania. Facility EPA ID #: PAD002290823
New: Click here to see:
Table 1. Top 50 Crops and Sites for for Cryolite use in California in 2002.
Table 2. Use by county in California for Cryolite on All Sites in 2002.
Table A. PAN's Explanation of Terms

Table 3. Cryolite Pesticide Use in California: 1991-2000
Table 4. 1992 - Estimated Cryolite Use in US (including map)
April 24, 2002 - Comments submitted to EPA on Gowan's petition for new, modified, and proposed tolerances. US EPA Docket control number OPP-2002-0007. From Paul and Ellen Connett.
Ref: 1995 - Summary of Toxicology Data. California EPA, Department of Pesticide Regulation, Medical Toxicology Branch.
... Results showed that fluorine of synthetic cryolite is retained significantly more than fluorine from natural cryolite, probably due to solubility. (Ref: The Assimilation of Fluorine by Rats From Natural and Synthetic Cryolite and From Cryolite-Sprayed Fruits, University of Illinois, 6/30/41)
1996 - US EPA Reregistration Eligibility Decision (RED)
Note from EC: Of all the EPA RED documents that I have read, this ranks as the most inadequate.
US Map of Pesticide Use - 1992 - 1995
TOXNET profile from Hazardous Substances Data Bank
Note: In the September 5, 2001 Federal Register, US EPA published a new risk assessment for inorganic fluoride. EPA included the fluoride risk assessment in a petition for the first-time use of Sulfuryl fluoride as a fumigant on post-harvest food commodities. Because fluoride is the endpoint of toxicological concern for both Cryolite and Sufluryl fluoride, the September 5, 2001 fluoride assessment is a critical addition to the literature. It is also essential reading for understanding the risks associated with inorganic fluoride pesticides.
Federal Register: July 6, 2000: Tebufenozide; Pesticide Tolerances for Emergency Exemptions... for the 2000 crop year, nearly all major California wineries with export markets have advised their growers that they will not accept grapes which have been treated with cryolite or any other product which would affect the level of fluorides in wine. The European Community recently established strict tolerance levels of 1 ppm with respect to fluoride residues. There is a direct correlation between even limited use of cryolite on wine grapes which can result in fluoride levels in wine above 3 ppm.
List of Insecticide products.
Manufacturer's Advisory on Use of Cryolite to Control Insects on Grapes - Kryocide®
1998 - German Trade Regulations on Fluoride Levels in Imported Wines - USDA's Foreign Agricultural Service
June 1996 - Levels in California Wines ranging to as high as 12 ppm in Zinfadel and French Colombard. - Fluoride in wines - A guide for growers and vintners to determine optimum cryolite applications on grapevines by Gwynn Sawyer Ostrom. CATI Publication #960601
June 1983 - Chemical Fact Sheet - Cornell PMEP

US Federal Register

•• Note: this is not a complete list of FR entries. Click here to see the full list.

Date published in FR Docket Identification Number Details
July 31, 2002 OPP-2002-0155 Tolerance Revocations for residues in or on beets, radishes, rutabagas, and turnips. FINAL RULE. EPA is revoking tolerances in 40 CFR 180.145 for residues of fluorine compounds cryolite and synthetic cryolite (sodium aluminum fluoride) in or on beets, roots; radish, roots; rutabaga, roots; and turnip, roots. The registrant(s) of cryolite requested voluntary cancellation for use on beets, radishes, rutabagas, and turnips. Rutabagas were removed from cryolite labels prior to 1988. Beets were removed from cryolite labels in 1988. On September 25, 1996 a FIFRA section 6(f)(1) notice of receipt of a request to voluntarily delete radish and turnip uses from cryolite registrations was published in the Federal Register (61 FR 50294) (FRL-5394-2), with a use deletion date of December 24, 1996. EPA believes that sufficient time has passed for stocks to have been exhausted and for treated commodities to have cleared channels of trade.
April 24, 2002 OPP-2002-0007

Gowan Company - New and modified tolerances. According to Gowan's petition: "The estimated dietary exposure in this assessment for cryolite... Grapes and grape products are the largest contributors to dietary exposure estimates for all population subgroups. Lettuce was also a significant source of exposure for adult populations." The following specific actions are proposed:

  • Modify existing tolerances:
    • Apricots from 7 ppm to 10 ppm
    • Cucumber from 7 ppm to 4 ppm
    • Cranberry from 7 ppm to 2 ppm
    • Kale from 7 ppm to 35 ppm
    • Kiwi from 15 ppm to 8 ppm
    • Nectarines from 7 ppm to 10 ppm
    • Plums from 7 ppm to 2 ppm (tolerance with regional registration)
  • Renew tolerances and remove time-limitation:
    • Potatoes - 2 ppm
    • Potatoes, waste from processing 22 ppm
  • Establish new tolerances:
    • Berries (crop group 13) - 0.5 ppm (replaces separate existing tolerances for blackberries, blueberries, boysenberries, dewberries, loganberries, raspberries and youngberries)
    • Prunes - 7 ppm (tolerance with regional registration)

Comments on this petition are due on or before May 24, 2002. It is essential for those who submit comments to refer to EPA's updated risk assessment on fluoride which was published in the September 5, 2001, Federal Register petition for the first-time use of Sulfuryl fluoride as a fumigant on food commodities.

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