| Chemical Abstract Number (CAS #) |
1563662
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| Synonyms | Carbofuran |
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Furadan | Carbamic acid, methyl-, 2,3-dihydro-2,2-dimethyl-7-benzofuranyl ester | 7-Benzofuranyl, 2,3-dihydro-2,2-dimethyl-, methylcarbamate |
| Analytical Methods |
EPA Method 531.1 |
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EPA Method 632 |
| Molecular Formula | C12H15NO3 |
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| Use | BROAD SPECTRUM INSECTICIDE, NEMATOCIDE, MITICIDE
SYSTEMIC ACARICIDE
FURADAN CONTROLS CORN ROOTWORM IN FIELD CORN; MOST SOIL & FOLIAR
PESTS; ALFALFA WEEVIL, APHIDS & LYGUS BUGS; NEMATODES, SOIL, FOLIAGE
FEEDING INSECTS IN TOBACCO; NEMATODES, THRIPS IN PEANUTS; RICE WATER
WEEVIL; NEMATODES, WIREWORMS, SUGARCANE BORER IN SUGARCANE;
GREENBUG IN SORGHUM; COLORADO POTATO BEETLE, LEAFHOPPERS, FLEA
BEETLES IN POTATOES; NEMATODES, MEXICAN BEAN BEETLE IN SOYBEANS;
SOIL, FOLIAR FEEDING INSECTS, NEMATODES IN SWEET CORN; THRIPS IN
COTTON; NEMATODES, PHYLLOXERA IN GRAPES; GRASSHOPPERS, CEREAL LEAF
BEETLE IN SMALL GRAINS; NEMATODES IN CUCURBITS; GRASSHOPPERS, STEM
WEEVILS, SUNFLOWER BEETLES IN SUNFLOWERS
CARBOFURAN IS EFFECTIVE AGAINST A NUMBER OF MITES WITH THE
EXCEPTION OF SOME TETRANYCHUS
OUTSIDE USA: OVERSEAS USES INCLUDE BANANAS, COFFEE AND SUGAR
BEETS. GRANULES ARE USED IN LOWLAND RICE AGAINST LEAFHOPPERS,
STEMBORERS, & CERTAIN OTHER INSECTS.
In Canada carbofuran is registered for use in control of out-breaks of grasshoppers using aerial
applications of carbofuran up to 140 g active ingredient/hectare.
Canada: Highest rate of carbofuran registered for the control of wireworms in potatoes at 5.6 kg
active ingredient/hectare.
Registered uses of carbofuran in Canada: Limitations are as follows: Do not apply to crops
within the following pre-harvest intervals (days): alfalfa (7); barley (21); corn (7); flax (21);
mustard (21); oats (21); pastures ; pepper, green ; potato (7); rape (60); rutabaga (40);
sweet clover (28); sunflower (60); tomato, field (30); turnip (40); wheat (21). Do not feed foliage
of treated turnips to livestock; mature roots may be fed. On alfalfa, do not apply during bloom, or
allow spray to drift toward beehives. Do not graze or feed to livestock within the following
intervals (days) after application: alfalfa (7); barley (21); corn ; oats (21); mustardseed (21);
pastures ; rape seed (60); sweet clover (28); wheat (21). Do not make more than the following
number of applications per season: barley ; flax ; mustard (1 at 140 g ai/ha or 2 at 70 g
ai/ha); oats ; pastures ; pepper, green (6); rape (1 at 140 g ai/ha or 2 at 70 g ai/ha);
sunflower ; sweet clover ; tomato, field ; wheat . Do not permit livestock to graze on
road sides or headlands within 1 day after application. Commercial class products limited to a
maximum carbofuran content of 10%.
For registered uses of carbofuran in Canada, limitations are as follows: Do not apply to crops
within the following pre-harvest intervals (days): alfalfa (7); barley (21); corn (7); flax (21);
mustard (21); oats (21); pastures ; pepper, green ; potato (7); rape (60); rutabaga (40);
sweet clover (28); sunflower (60); tomato, field (30); turnip (40); wheat (21); Do not feed foliage
of treated turnips to livestock; mature roots may be fed. On alfalfa, do not apply during bloom, or
allow spray to drift toward beehives. Do not graze or feed to livestock within the following
intervals (days) after application: alfalfa (7); barley (21); corn ; oats (21); mustardseed (21);
pastures ; rape seed (60); sweet clover (28); wheat (21). Do not make more than the following
number of applications per season: barley ; flax ; mustard (1 at 140 g ai/ha or 2 at 70 g
ai/ha); oats ; pastures ; pepper, green (6); rape (1 at 140 g ai/ha or 2 at 70 g ai/ha);
sunflower ; sweet clover ; tomato, field ; wheat . Do not permit livestock to graze on
road sides or headlands within 1 day after application. Commercial class products limited to a
maximum carbofuran content of 10%. UNREVIEW
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| Consumption Patterns | ABOUT 82% AS AN INSECTICIDE ON CORN; ABOUT 15% AS AN
INSECTICIDE ON ALFALFA; AND THE BALANCE ON TOBACCO AND OTHER FIELD
CROPS (1974)
Applied to Alfalfa, 47.1%; Rice, 42.2%; Turf, 6.7%; Grapes, 2.4% Remainder on other grains,
fruits and vegetables, and non-food crops (1984) California use, calculated from table
(1984) 9.35X10 7 g California use, calculated from table
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| Apparent Color | WHITE, CRYSTALLINE SOLID
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| Odor | ODORLESS (PURE MATERIAL); Slightly phenolic.
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| Melting Point | 153-154 deg C (pure)
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| Molecular Weight | 221.26
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| Density | 1.180 AT 20 DEG C/20 DEG C
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| Environmental Impact | The dominant source of carbofuran emission to the environment is the application of the
compound as an insecticide. If released to soil, chemical hydrolysis and microbial degradation
appear to be the important degradation processes. Chemical hydrolysis is expected to occur more
rapidly in alkaline soil as compared to neutral or acidic soils. Results of various degradation
studies comparing sterile versus nonsterile soil suggest that soil biodegradation may be important.
The rate of degradation of carbofuran in soil is greatly increased by pretreatment with carbofuran.
The major metabolites of carbofuran degradation in soil are 3-hydroxycarbofuran,
3-ketocarbofuran and carbofuran phenol. Experimentally measured Koc values ranging from 14 to
160 indicate that carbofuran may leach significantly in many soils; its detection in water table
aquifers beneath sandy soils in NY and WI indicate leaching has occurred. Leaching may not
occur, however, in very high organic content soils (65% carbon). Volatilization from soil is not
expected to be significant, although some evaporation from plants may occur. A review of
literature reported the following half-lives for carbofuran disappearance in soil: 2-72 days in
laboratory studies, 2-86 days for flooded soils and 26-110 days for field soil. If released to water,
carbofuran will be subject to significant hydrolysis under alkaline conditions. The hydrolysis
half-lives in water at 25 deg C are 690, 8.2 and 1.0 weeks at pH 6.0, 7.0 and 8.0, respectively.
Direct photolysis and photooxidation (via hydroxyl radicals) may contribute to carbofuran's
removal from natural water and may become increasingly important as the acidity of the water
increases and the hydrolytic half-life increases. Since carbofuran appears to be susceptible to
degradation by soil microbes, aquatic microbes may also be able to degrade carbofuran. Aquatic
volatilization, adsorption, and bioconcentration are not expected to be important. The half-lives
for degradation of carbofuran in river, lake, and seawater from Greece which was irradiated with
sunlight were approximately 2, 6, and 12 hours, respectively. The approximated half-lives
observed for degradation of carbofuran in sterilized and non-sterilized natural water (pH = 7.8-8.0
and 7.8, respectively) collected from the Holland Marsh, Ontario, were 2.5 and 3 weeks. If
released to air, carbofuran will react in the vapor-phase with photochemically produced hydroxyl
radicals at an estimated half-life of 7.8 hr. Direct photolysis may be important removal process for
carbofuran in the atmosphere. Occupational and general population exposure to carbofuran may
occur by inhalation and dermal routes, particularly in the vicinity of aerial spraying of carbofuran
as an insecticide.
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| Environmental Fate | TERRESTRIAL FATE: No appreciable degradation of carbofuran occurred in kari soil
(pH 4.8; organic matter 11.8%) until 30 days after flooding, but at the end of 40 days, more than
81% of carbofuran degraded followed by steady increase in recovery of nonextractable soil bound
residues. Autoradiographic analysis showed that carbofuran phenol (major) &
3-hydroxycarbofuran were carbofuran metabolites in soil. The mechanism of degradation in
flooded soils was studied by using (14)C-carbofuran.
TERRESTRIAL FATE: If carbofuran is released to soil, it will be subject to degradation by
both chemical and biological processes . A review of available literature reported the half-lives
for carbofuran disappearance in soil as follows: 2-72 days in laboratory studies, 2-86 days for
flooded soils, and 26-110 days for soil in the field . The rate of degradation of carbofuran in soil
is greatly increased by pretreatment with carbofuran(3,4). Chemical hydrolysis (in aqueous
solution) occurs much more rapidly under alkaline conditions . Therefore, the pH of the soil is
likely to be a major factor in determining the rate of disappearance; several studies have shown
that carbofuran is decomposed faster in alkaline soils as compared to neutral or acidic soils .
Results of various degradation studies comparing sterile versus nonsterile soil suggest importance
of soil biodegradation(6,7). The major metabolites of carbofuran degradation in soil are
3-hydroxycarbofuran, 3-ketocarbofuran and carbofuran phenol . Experimentally measured Koc
values ranging from 14 to 160(3,8) indicate that carbofuran may leach significantly in many soils
and its detection in water table aquifers beneath sandy soils in NY and WI(9) indicates that
leaching has occurred. Leaching did not occur, however, in an onion field containing a high
organic matter content (65%) during 10 weeks of monitoring(10). Volatilization from soil is not
expected to be significant(11), although some evaporation may occur from plants(12).
TERRESTRIAL FATE: Carbofuran was incorporated in soils & its disappearance monitored.
Disappearance of 95% of carbofuran varied between 145 & 434 days as a function of
temperature, moisture, & soil pH & followed first-order kinetics.
TERRESTRIAL FATE: In 4 soils with known insecticide use, the technical carbofuran had a
calculated half-life of 11-13 days (pH 6.5) & the granular formulation had a half-life of 60-75 days
(pH 6.5). Time of disappearance from the soil at 3.1 to 5.6 kg/hectare was 145 to 434 days.
AQUATIC FATE: If carbofuran is released to water, it will not be expected to subject to
volatilization, adsorption to sediment or suspended particulate matter(4,5), or to bioconcentration
in aquatic organisms(6). The hydrolysis half-lives of carbofuran in water are about 690, 8.2 and
1.0 weeks at pH 6.0, 7.0 and 8.0, respectively, at 25 deg C indicating that hydrolysis in alkaline
water will be important . Direct photolysis and photooxidation (via hydroxyl radicals) may
contribute to carbofuran's removal from natural water and may become increasingly important as
the acidity of the water increases and the hydrolytic half-life increases. Since carbofuran
appears to be susceptible to degradation by soil microbes(7), aquatic microbes may also be able to
degrade carbofuran. The half-lives for degradation of carbofuran in river, lake, and
seawater from Greece which was irradiated with sunlight were approximately 2, 6, and 12 hours,
respectively . The approximate half-lives observed for degradation of carbofuran in sterilized
and non-sterilizaed natural water (pH = 7.8-8.0 and 7.8, respectively) collected from the Holland
Marsh, Ontario, were 2.5 and 3 weeks, respectively, were due primarily to chemical processes .
ATMOSPHERIC FATE: If carbofuran is released to the atmosphere, it will be suject to vapor
phase photooxidation via reaction with hydroxyl radicals . The half-life for the vapor-phase
reaction of carbofuran with photochemically produced hydroxyl radicals has been estimated to be
7.8 hr in a typical atmosphere . Direct photolysis may be an important removal process for
carbofuran in the atmosphere . Carbofuran on particulates suspended in air during aerial
spraying of the insecticide is subject to dry and wet deposition.
TERRESTRIAL FATE: The persistence of carbofuran in the soil will increase as 1) the
application rate increases; 2) the clay content of the soil increases; 3) the organic matter content
of the soil increases; 4) the pH decreases; 5) the moisture content of soil decreases.
TERRESTRIAL FATE: Carbofuran behavior was studied in 2 drained cornfield soils (clay and
loamy clay) for 2 successive yr. The persistence values (total residence time) obtained were 56
and 63 days for the first and second yr. Drained water from soil rich in organic matter was found
to have a higher carbofuran content, with 7.1-13.7% and 2.5-5.0% of the applied dose for clay
and loamy clay soils, respectively. The major part of these percentages arose from the drained
waters associated with rainfall occurring during the first 2-3 wk after application.
TERRESTRIAL FATE: Half-life in soil is about 30-60 days.
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| Drinking Water Impact | GROUNDWATER: Carbofuran has been found in ground water in WI and NY in areas
with sandy soils and water table aquifers at levels typically between 1 and 5 ppb . Carbofuran
was detected (detection limit 1 ppb), not quantified, in well water samples taken in 1984 from 5 to
91 farms in Southern Ontario, Canada . The Ground Water Data Base 1988 Interim Report lists
three confirmed states (NY, MA, RI) in which carbofuran has been found due to agricultural use
and point source contamination . The max concn of the confirmed detections is 176 ppb and the
median concn is 5.30 ppb .
SURFACE WATER: Carbofuran has been detected (concn not reported) in surface waters
associated with Lake Erie and Lake Huron . An overall mean carbofuran concn of less than 0.1
ng/l was detected in 11 agricultural watersheds in Ontario during 1976-77 with the highest
monitored concn being 1.80 ng/l; the presence of the carbofuran in the watersheds was thought to
have occurred by storm water runoff, soil drainage and spills . Carbofuran was found in samples
from the following Michigan Rivers in 1985 at t the indicated concn ranges in the positive
samples: Black 0.100-0.473 ppb; Belle, 0.009-0.266 ppb; Pine, 0.056-0.250 ppb; and Clinton,
0.18-0.413 ppb .
DRINKING WATER: Between May-July 1986, carbofuran was detected (detection limit 0.1
ppb) in 9 of 33 treated (finished) public water supplies using surface water as a source at a concn
of 0.18-14.0 ppb and at an avg concn of positive detections of 3.76 ppb . Carbofuran was
detected also in 5 of 15 of the surface water sources at a concn of 0.72-17.0 ppb and at an avg
concn of positive detections of 7.1 ppb . The water samples in the above study were taken after
rainfall .
RAIN/SNOW: Samples of rainwater collected during spring and summer 1985 were analyzed
for the presence of carbofuran . Carbofuran was detected at a concn range of 0.1-0.5 ppb in the
samples of rainwater from the following locations (number of samples at indicated concn): West
Lafayette, IN (2 of 14 samples), Tiffin, OH (1 of 25 samples), Parsons, WV (1 of 20 samples),
and Potsdam, NY (1 of 21 samples) . Carbofuran also was detected, not quantified, in 1 of 21
samples from Potsdam, NY .
Waters from 21 wells and 2 springs located in a typically farmed, mostly agricultural PA
watershed (the Mahantango Creek Watershed) were analyzed for 11 pesticides, including
carbofuran. Pesticides were selected according to a farm use survey, and samplings were made
during Dec 1985, Aug 1986, and Mar/Apr 1987. Carbofuran was not applied in 1985, but was
applied to about 85% of the area at 1.2 kg/ha in 1986. No carbofuran was found in any sampling
(< 15 ng/l).
EFFL: Carbofuran was detected (detection limit 1 ppb), not quantified, in well water samples
taken in 1984 from 5 of 91 farms in Southern Ontario, Canada . Concn of carbofuran in runoff
into a hydroelectric lake in GA from a carbofuran-treated pine seed orchard ranged from not
detected to 6580 ppb; the runoff event with the maximum detected concn produced a minor fish
kill in the lake . Thirty-one tailpits collecting irrigation runoff from corn and sorghum fields in
Haskell County KS in 1974 were found to contain a mean concn of 24.1-35.2 ppb carbofuran in
the tailpit water .
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