TRADE OR OTHER NAMES
Vikane
REGULATORY STATUS
All formulations of sulfuryl fluoride are Restricted Use Pesticides
(RUP) and must bear the signal word "Danger" on the
product label, because it poses an inhalation hazard (1,
4). RUPs may be purchased and used only by certified
applicators.
INTRODUCTION
Sulfuryl fluoride is a gas fumigant used in structures, vehicles
and wood products for control of drywood termites, wood-infesting
beetles and certain other insects (1, 5).
There are no registered uses for sulfuryl fluoride on food or
feed crops (4).
TOXICOLOGICAL EFFECTS
ACUTE TOXICITY
Sulfuryl fluoride is a toxic gas which acts as a central nervous
system depressant (2). Symptoms of poisoning
include depression, slowed gait, slurred speech, nausea, vomiting,
stomach pain, drunkenness, itching, numbness, twitching, and seizures
(2, 6). Inhalation may be fatal
due to respiratory failure (1). Inhalation of
high concentrations may cause respiratory tract irritation (2).
Individuals with a history of chronic respiratory disease are
at increased risk from exposure to sulfuryl fluoride (2).
Skin contact with sulfuryl fluoride normally poses no hazard,
but contact with liquid sulfuryl fluoride can cause pain and frostbite
due to rapid vaporization (2).
Sulfuryl fluoride gas is odorless, colorless, does not cause
tears or immediately noticeable eye irritation, and lacks any
other property which would serve to warn persons of its presence
(4). Chloropicrin is added to products containing
sulfuryl fluoride to serve as a warning indicator.
Chloropicrin is a gas which causes eye and respiratory irritation
and vomiting.
The oral LD50 for sulfuryl fluoride in rats and guinea pigs is
100 mg/kg (2). The 4-hour inhalation LC50 in
rats is 991 ppm (2). The 1-hour LC50 in mice
is 1,200 ppm, and in rabbits is 5,000 ppm (b). Concentrations
of 1,000 ppm are immediately threatening to life and health (2).
CHRONIC TOXICITY
Long term exposure to high levels of sulfuryl fluoride may cause
blood and bone effects (2). Repeated or prolonged
exposure to sulfuryl fluoride may cause injury to lungs and kidneys,
weakness, weight loss, anemia, bone brittleness, stiff joints,
and general ill health (2). Long-term effects
from sulfuryl fluoride may be due to the formation of fluoride
ions (3, 4).
Rats, rabbits, guinea pigs and female rhesus monkeys tolerated
air concentrations of 100 ppm (417 mg/m3) for 7 hours per day,
5 days a week for 6 months with no apparent adverse effects (3).
Reproductive Effects
Two generations of rats were exposed to air concentrations of
0, 5, 20 or 150 ppm. No adverse effects on reproduction or fertility
were seen at any dose. Toxic effects on the mother were accompanied
by reduced pup weight at the 150 ppm exposure level (7).
Teratogenic Effects
There were no birth defects in the offspring of pregnant rabbits
and rats exposed to air concentrations of 255 ppm, the highest
dose tested, during days 6-18 (rabbits) or days 6 through 15 (rats)
of pregnancy for 6 hours/day. In rabbits, both the fetuses and
the mothers exhibited decreased weight gain at 255 ppm (4).
Mutagenic Effects
Several tests have shown that sulfuryl fluoride is not mutagenic.
It failed to produce unscheduled DNA synthesis in rat liver cells
exposed to concentrations between 204 and 1,020 ppm (8).
Examination of bone marrow from mice exposed to air concentrations
of 50, 175 or 520 ppm sulfuryl fluoride for 4 hours showed no
mutagenic effects (9). When sulfuryl fluoride
was assayed with the Ames test for mutagenic effects in bacterial
cell cultures, the results were negative (10).
Carcinogenic Effects
Tests for carcinogenicity are currently being conducted.
Organ Toxicity
No information was found.
Fate in Humans and Animals
No information was found.
ECOLOGICAL EFFECTS
Effects on Birds
Sulfuryl fluoride is a gas under normal conditions. It dissipates
extremely rapidly after release into the environment. Exposure
to birds is expected to be only at very low concentrations and
of short duration.
Effects on Aquatic Organisms
Because use of sulfuryl fluoride is permitted only indoors, compliance
with label directions will prevent exposure of aquatic organisms.
Effects on Other Animals (Nontarget species)
No information was found.
ENVIRONMENTAL FATE
Environmental effects from sulfuryl fluoride are expected to
be negligible because this fumigant is applied only indoors or
in sealed structures (4).
Breakdown of Chemical in Soil and Groundwater
Sulfuryl fluoride is a gas. It will not leach or contaminate
groundwater.
Breakdown of Chemical in Surface Water
Sulfuryl fluoride is not readily hydrolyzed by water (3).
The products of hydrolysis are sulfate and fluoride.
Breakdown of Chemical in the Atmosphere
Sulfuryl fluoride dissipates quickly in the atmosphere and is
broken down through hydrolysis and photodegradation.
PHYSICAL PROPERTIES AND GUIDELINES
Sulfuryl fluoride is a colorless, odorless, compressed gas (1).
It is stable under normal temperatures and pressures, but containers
may rupture in the heat of a fire. Keep containers away from heat
and flame and avoid breathing the gas or contact of the gas with
eyes, skin and clothing. Use only where there is adequate ventilation
(2). Thermal decomposition may release toxic
and corrosive fumes of hydrogen fluoride and oxides of sulfur
(2). Fire causes the product Vikane to break
down to a very corrosive substance (6).
Persons handling sulfuryl fluoride should not work alone (6).
Exposure Guidelines: