United States Office of Water EPA 811-F-95-003 f-T
Environmental Protection 4601 October 1995
Agency
National Primary Drinking
Water Regulations
Carbofuran
CHEMICAL/ PHYSICAL PROPERTIES
OCTANOL/WATER PARTITION (Kow):
Log Kow = 2.32
CAS NUMBER: 1563-66-2
DENSITY/SPEC. GRAV.: 1.18 at 20° C
COLOR/ FORM/ODOR: White crystalline solid
with a slightly phenolic odor. Available SOLUBILITY: 0.7 g/L of water at 25° C;
as a flowable paste or wettable Slightly soluble in water
powder.
M.P.: 153-154°C B.P.: N/A
VAPOR PRESSURE:
3.4x10-6 mm Hg at 26.1 ° C
SOIL SORPTION COEFFICIENT:
mean Koc of 29.4;
significant mobility in soil
ODOR/TASTE THRESHOLDS: N/A
BlOCONCENTRATION FACTOR:
117. in one species of fish; not expected
to bioconcentrate in aquatic organisms.
HENRY'S LAW COEFFICIENT:
1.02x10-10 atm-cu m/mole;
TRADE NAMES/SYNONYMS:
Niagara 10242, Furadan 4F or3G,
Brifur, Crisfuran, Chinufur, Curaterr,
Yaltox, Pillarfuran, Kenofuran,
DRINKING WATER STANDARDS
MCLG: 0.04 mg/L
MCL: 0.04 mg/L
HAL(child): 1 day: 0.05 mg/L
Longer-term: 0.05 mg/L
HEALTH EFFECTS SUMMARY,
USAGE PATTERNS
A1984 report estimated that application on alfalfa and
rice accounted for about 90% of carbofuran use, with turf
and grapes making up most of the remainder. Earlier
uses were primarily on com crops. This broad spectrum
insecticide is sprayed directly onto soil and plants just
after emergence to control beetles, nematodes and root-
worm.
Acute: EPA has found carbofuran to potentially cause After September 1994, carbofuran will be allowed for
a variety of nervous system effects from acute expo- use on only five U.S. crops: bananas (in Hawaii); pump-
sures, including: headache, sweating, nausea, diarrhea, kins, cucumbers, watermelons, cantaloupes and squash;
chest pains, blurred vision, anxiety and general muscular dry harvested cranberries,; pine progeny tests; and spin-
weakness. These effects are largely due to carbofuran's ach grown for seed..Carbofuran will soon be banned from
rapid inhibition of cholinesterase activity, and is generally use on corn and sorghum in California.
reversible once exposure ceases.
Drinking water levels which are considered "safe" for RELEASE PATTERNS
short-term exposures: For a 10-kg (22 Ib.) child consum- carbofuran enters surface water as a result of runoff
ing 1 liter of water per day, upto a 7-year exposure to 0.05 from treated fie|ds and enters ground water by Caching
mg/L. Of treated crops.
Chronic: Available data on chronic toxic effects from EpA-s 1 g90 National Pesticide Survey did not detect
oral exposures to carbofuran have shown that low doses carbofuran levels above the MCL in rural domestic wells
of carbofuran appear to have little or no adverse health or Community Water System wells. EPA's Pesticides in
effects. Higher doses have the potential to cause dam- Ground Water Database reports few detections of
age to the nervous and reproductive systems. carbofuran in ground water between 1971 and 1991.
Cancer: There is no evidence that carbofuran has the
potential to cause cancer from lifetime exposures in ENVIRONMENTAL FATE
•linking water. ,, , . . .. , . ,. . , . . . .. -
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
October 1995
Technical Version
Printed on Recycled Paper
-------
acidic soils. Soil biodegradation may be important, with
the rate of degradation of carbofuran in soil greatly
increased by pretreatment with carbofuran.
Experimentally measured Koc values ranging from 14
to 160 indicate that carbofuran may leach significantly in
many soils, as has been seen in the detection of carbofuran
in water table aquifers beneath sandy soils in NY and Wl.
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 hy-
drolysis 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 degra-
dation by soil microbes, aquatic microbes may also be
able to degrade carbofuran. The half-lives for degrada-
tion of carbofuran in different waters ranges from several
hours to a few weeks.
Aquatic volatilization, adsorption, and bioconcentra-
tion are not expected to be important.
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 atmo-
sphere.
OTHER REGULATORY INFORMATION
MONITORING:
FOR GROUND/SURFACE WATER SOURCES:
INITIAL FREQUENCY- 4 quarterly samples every 3 years
REPEAT FREQUENCY- If no detections during initial round:
2 quarterly per year if serving >3300 persons;
1 sample per 3 years for smaller systems
TRIGGERS - Return to Initial Freq. if detect at > 0.0009 mg/L
ANALYSIS:
REFERENCE SOURCE METHOD NUMBERS
EPA 600/4-88-039 531.1
Standard Methods 6610
TREATMENT:
BEST AVAILABLE TECHNOLOGIES
Granular Activated Charcoal
FOR ADDITIONAL INFORMATION:
* EPA can provide further regulatory and other general information:
• EPA Safe Drinking Water Hotline - 800/426-4791
4 Other sources of toxicological and environmental fate data include:
• Toxic Substance Control Act Information Line - 202/554-1404
• Toxics Release Inventory, National Library of Medicine - 301/496-6531
• Agency for Toxic Substances and Disease Registry - 404/639-6000
• National Pesticide Hotline - 800/858-7378
October 1995
Technical Version
Page 2
------- |