From:  Cornell U. Pesticide Management Education Program

sodium aluminum fluoride (cryolite) Chemical Fact Sheet 6/83

CHEMICAL FACT SHEET FOR: CRYOLITE

FACT SHEET NUMBER: 02

DATE ISSUED:  JUNE, 1983

         1.  DESCRIPTION OF CHEMICAL

– Generic Name:  Sodium fluoaluminate or sodium aluminofluoride
– Common Name:  cryolite (natural or synthetic)
– Trade Name:  Kryocide
– EPA Shaughnessy Code:  075101
– Chemical Abstracts Service (CAS) Number:  15096-52-3 or 1344-75-8
– Year of Initial Registration:  about 1967
– Pesticide Type:  Insecticide
– Chemical Family:  Aluminofluoride salt
– U.S. and Foreign Producer:  Pennwalt Corporation

     2.  USE PATTERNS AND FORMULATIONS

– Application sites:  domestic and non-domestic terrestrial food crops
and ornamentals
– Types of formulations:  wettable powder, dusts
– Types and methods of application:  aerial or ground application as a
spray or dust
– Application rates:  varies from 6 to 50 lbs./acre
– Usual carriers:  Confidential Business Information
– Efficacy review results:  no efficacy data required

3.  SCIENCE FINDINGS

Chemical Characteristics

– Technical grade cryolite may be the naturally occurring fluoride of
sodium and aluminum called natural cryolite, or it may be the
manufactured material of similar composition called synthetic
cryolite.  Both forms are a solid, with melting points of 1000 degrees
C for the synthetic and 1009 degrees C for the natural cryolite.
Natural cryolite may be white, black, purple, or violet.  The
synthetic cryolite is white.  cryolite is completely stable under
normal storage conditions.  There are no unusual handling
characteristics.

Toxicological Characteristics

– No toxicological hazards of concern have been identified based on
the studies reviewed for the standard.
– Acute dermal LD50, rabbit:  >2.1 g/kg (Tox Category III)
– Acute inhalation LD50:  <5.03 mg/l, 2.06 mg/l (Tox Category III)
– Primary dermal irritation, rabbit:  P.I. score = 0.0, not an
irritant (Tox Category IV)
– Primary eye irritation, rabbit:  moderate conjunctival irritation
that disappeared within 7 days (Tox Category III)
– A sequential testing approach is being applied to this compound
because the chemical properties are unique.  Therefore, after review
of the studies required under the standard (a 90-day feeding study
in the rat and dog), additional subchronic and chronic studies may
be required.

Physiological and Biochemical Behavioral Characteristics

– Mechanism of pesticidal action:  stomach poison
– Mechanism and persistence in plants and animals:  not known

Environmental Characteristics

There are no available data on cryolite.  However, based on the
chemical and physical characteristics, none of the usual environmental
fate data normally required would yield useful information, with the
exception of hydrolysis and leaching studies which are required under
the standard.

Ecological Characteristics

– Based on current data, cryolite has been determined to be
practically non-toxic to bobwhite quail and mallard ducks in
subacute doses; however, hazards to birds, fish and aquatic
invertebrates may be greater than previously supposed.  Additional
data are required to address this concern.
– Dietary LC50 (mallard duck and bobwhite quail):  >10,000 ppm
(practically nontoxic)
– Freshwater invertebrates LC50 (Daphnia pulex):  10 ppm (moderately
toxic)
– Fish acute LC50 (rainbow trout):  47 ppm (slightly toxic)
– Fish acute LC50 (bluegill sunfish):  >300 ppm (practically
nontoxic)

Tolerance Assessment

– Tolerances have been established (40 CFR 10.145) of 7 ppm of
combined fluorine for residues of the insecticidal fluorine
compounds cryolite and synthetic cryolite in or on each of the
following raw agricultural commodities:  apples, apricots, beans,
beets (with or without tops) or beet greens alone, blackberries,
blueberries (huckleberries), boysenberries, broccoli, brussels
sprouts, cabbage, carrots, cauliflower, citrus fruits, corn,
collards, cranberries, eggplants, grapes, kale, kohlrabi, lettuce,
loganberries, melons, mustard greens, nectarines, okra, peaches,
peanuts, pears, peas, peppers, plums (fresh prunes), pumpkins,
quinces, radishes (with or without tops) or radish tops,
raspberries, rutabagas (with or without tops) or rutabaga tops,
squash, strawberries, summer squash, tomatoes, turnips (with or
without tops) or turnip greens, youngberries.
– Specific residue data are being required on a number of crops.  The
Agency will assess all cryolite tolerances after the necessary
toxicity and residue data are received.  Residue data are required
to ascertain the need for food additive tolerances for the following
processed commodities:  apple pomace (wet and dry), apple juice,
bean cannery waste, citrus (peel, oil, dried pulp, and molasses),
corn (oil and milled fractions), mustard seed, tomato pomace (wet
and dry, juice, puree, catsup).
– Livestock feeding studies are required to ascertain the extent of
carryover (if any) into meat, milk, poultry and eggs, and the need
to establish tolerances for these commodities.

Summary Science Statement

– Based on data reviewed for the Cryolite Standard, cryolite exhibits
low to moderate toxicity to humans (Toxicity Category III-IV), fish,
and wildlife.
– However, since a number of toxicology and residue data gaps exist,
the Agency is unable to complete a risk assessment.

     4. SUMMARY OF REGULATORY POSITION AND RATIONALE

– Use classification:  not classified
– Use restrictions:  none
– Unique warning statements:  none
– No toxicological hazards of concern have been identified in the
studies reviewed for this standard.  However, since a number of
toxicology and residue data gaps exist, the Agency is unable to
complete a risk assessment of cryolite.

       5. SUMMARY OF MAJOR DATA GAPS

– Product chemistry:  most of these data are lacking for the natural
cryolite.  Data to be submitted by December 1983.
– Residue chemistry:  residue data are lacking on all crops for which
tolerances are established with the exception of grapes.  Further,
there are no data available on the processing of commodities other
than raisins.  Livestock feeding studies are required to ascertain the
extent of carryover (if any) into meat, milk, poultry, and eggs.  Data
must be submitted by dune 1986.
– Toxicology:  oral LD50 (rat), dermal sensitization, 90-day feeding
(rat and dog), mutagenicity studies.  Chronic studies may be required
following receipt and evaluation of acute, subchronic, and residue
data.  Data must be submitted by December. 1983.
– Environmental fate:  hydrolysis and leaching studies.  Data must be
submitted by June 1986.

    6. CONTACT PERSON AT EPA

William H. Miller
Product Manager (16)
Insecticide-Rodenticide Branch
Registration Division (TS-767)
Environmental Protection Agency
Washington, DC  20460
(703) 557-2600

DISCLAIMER:  THE INFORMATION PRESENTED IN THIS CHEMICAL INFORMATION FACT
SHEET IS FOR INFORMATIONAL PURPOSES ONLY AND NOT TO BE USED TD FULFILL
DATA REQUIREMENTS FOR PESTICIDE REGISTRATION AND REREGISTRATION.