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Revised June 1996
Chloropropham
Trade and Other Names:
Trade names include Beet-Kleen, Bud Nip, Chloro IPC, CIPC,
Furloe, Sprout Nip, Spud-Nic, Taterpex, Triherbide-CIPC and
Unicrop CIPC.
Regulatory Status:
Chlorpropham is a General Use Pesticide (GUP). The U.S.
Environmental Protection Agency classifies it as toxicity class
III - slightly toxic. Products containing it bear the Signal Word
CAUTION.
Chemical Class:
carbamate
Introduction:
Chlorpropham, a member of the carbamate family of chemicals, is a
plant growth regulator. It is used for preemergence control of
grass weeds in alfalfa, beans, blueberries, cane berries,
carrots, cranberries, ladino clover, garlic, seed grass, onions,
spinach, sugar beets, tomatoes, safflower, soybeans, gladioli and
woody nursery stock. It is also used to inhibit potato sprouting
and for sucker control in tobacco. It works by inhibiting root
growth and photosynthesis. Chloropropham is available as
granules, dustable powder, and emulsifiable concentrate.
Formulation:
Chloropropham is available as granules, dustable powder, and
emulsifiable concentrate.
Toxicological Effects:
- Acute toxicity: Chlorpropham may cause
irritation of the eyes or skin [8]. Symptoms of poisoning
in laboratory animals exposed to high doses have included
listlessness, incoordination, nose bleeds, protruding
eyes, bloody tears, difficulty in breathing, prostration,
inability to urinate, high fevers, and death. Autopsies
of animals have shown inflammation of the stomach and
intestinal lining, congestion of the brain, lungs and
other organs, and degenerative changes in the kidneys and
liver [8]. The oral LD50 for chlorpropham in rats ranges
from 5000 mg/kg to 7500 mg/kg [10]. In rabbits the LD50
is 5000 mg/kg [10]. The 4-hour inhalation LC50 in rats is
greater than 32 mg/L [35].
- Chronic toxicity: Not Available
- Reproductive effects: In reproductive
studies with rats, 500 mg/kg/day, the highest dose
tested, produced no adverse effects [4]. The evidence
suggests that chlorpropham does not cause reproductive
effects, even at high doses.
- Teratogenic effects: No birth defects
occurred in a three-generation study of rats exposed to
chlorpropham [35]. No teratogenic effects were observed
in rabbits at doses up to 250 mg/kg/day [31].
- Mutagenic effects: Mutagenicity studies
indicate that chlorpropham is either non-mutagenic or
slightly mutagenic [8].
- Carcinogenic effects: No evidence of
carcinogenicity was found in one study of rats fed
chlorpropham. This suggests that the pesticide is not
carcinogenic, but does not provide conclusive evidence
[8].
- Organ toxicity: Chronic exposure of
laboratory animals has caused retarded growth, increased
liver, kidney and spleen weights, and lesions of the
spleen [4].
- Fate in humans and animals: No data are
currently available.
Ecological Effects:
- Effects on birds: Chlorpropham is
practically non-toxic to waterfowl [4]. Its LD50 in
mallards is greater than 2000 mg/kg [10].
- Effects on aquatic organisms:
Chlorpropham is moderately toxic to cold and warm water
freshwater fish. The LC50 (48-hour) for chlorpropham is
12 mg/L in bluegill sunfish [10]. The LC50 is 10 mg/L in
bass [10].
- Effects on other organisms: Chlorpropham
has no effect on streptomyces bacteria or on nitrifying
bacteria. It is not dangerous to bees when used as
recommended [10].
Environmental Fate:
- Breakdown in soil and groundwater:
Chlorpropham is moderately persistent in soil. It is
subject to degradation by soil microbes. Photodegradation
and volatilization do not readily occur. Soil half-lives
of 65 days at 15 C to 30 days at 29 C have been reported
[13]. Chlorpropham has some potential to contaminate
groundwater because it is soluble in water and it has
only a moderate tendency to adsorb to soil particles
[13]. However, chlorpropham adsorbs strongly to organic
matter, so it is unlikely to leach through soils with
high organic matter content [13].
- Breakdown in water: Chlorpropham breaks
down very slowly by reaction with water. At pH 4, 7 and 9
at 40 C, about 90% of the chlorpropham remained in a
solution maintained in the dark for 32 days [41].
- Breakdown in vegetation: Chlorpropham is
absorbed by the roots of susceptible grass seedlings and
transported throughout the plant. It is absorbed more
slowly by leaves [35].
Physical Properties:
- Appearance: Technical chloropropham is a
white to light brown crystalline solid. It is stable
under normal temperatures and pressures, but poses a
slight fire hazard if exposed to heat or flame, and is a
fire and explosion hazard in the presence of strong
oxidizers. It may burn but will not readily ignite.
Thermal decomposition may release highly toxic fumes of
phosgene, toxic and corrosive fumes of chlorides, and
oxides of carbon.
- Chemical Name: isopropyl
3-chlorophenylcarbamate
- CAS Number: 101-21-3
- Molecular Weight: 213.67
- Water Solubility: 89 mg/L @ 25 C [10]
- Solubility in Other Solvents: benzene
v.s.; xylene v.s.; chloroform v.s.; ketones v.s.; acetone
v.s.; methanol v.s.; esters v.s.; minerals and oils s.
[10]
- Melting Point: 41.4 C [10]
- Vapor Pressure: 1.33 mPa @ 25 C [13]
- Partition Coefficient: Not Available
- Adsorption Coefficient: 400 (estimated)
Exposure Guidelines:
- ADI: Not Available
- MCL: Not Available
- RfD: 0.2 mg/kg/day [20]
- PEL: Not Available
- HA: Not Available
- TLV: Not Available
Basic Manufacturer:
ELF Atochem North America, Inc.
2000 Market Street
Philadelphia, PA 19103-3222
- Phone: 215-419-7219
- Emergency: 800-523-0900
References:
References for the information in this PIP can be found in
Reference List Number 3
DISCLAIMER: The
information in this profile does not in any way replace or
supersede the information on the pesticide product labeling or
other regulatory requirements. Please refer to the pesticide
product labeling.