United States Office of Water EPA 811 -F-95-003 c-T
Environmental Protection 4601 October 1995
Agency
o-EPA National Primary Drinking
Water Regulations
Aldicarb and Aldicarb Metabolites
CHEMICAL/ PHYSICAL PROPERTIES OCTANOL/WATER PARTITION (Kow): BIOCONCENTRATION FACTOR:
Log Kow = 1.13 42 in fish; not expected to bioconcen-
CAS NUMBER: 116-06-3 trate in aquatic organisms.
DENSITY/SPEC. GRAV.: 1.2at25°C
COLOR/FORM/ODOR: HENRY'S LAW COEFRCIENT:
White crystals with slightly sulfurous SOLUBILITY: 17 ug/L of water at 25° C ., 5x1 Q.a g^^ m/mole;
odor; Available in granular formulations c
containing 5 to 15% aldicarb , SO.L SORPT.ON COEFRC.ENT: TRADE NAMES/SYNONYMS:
Koc ranges from 8-37; high to very Temik; Carbamyl; Carbanolate; Sulfone
M.P.: 99-100° C B.P.: N/A high mobility in soil aldoxycarb; Union Carbide 21149
VAPOR PRESSURE: 1x10^ mm Hg at 25° C ODOR/TASTE THRESHOLDS: N/A
DRINKING WATER STANDARDS (IN uo/L) ing crops; cotton, sugar beet, fodder beet, strawberries,
MCLG MCL HAL(CHILD) potatoes, onions, hops, vine nurseries, tree nurseries,
0 groundnuts, soya beans, citrus fruit, bananas, coffee,
Aldicarb 0.001 0.003 none sorghum, pecans, sweet potatoes & other crops. Cotton
Aldicarb Sulfone 0.001 0.003 none crops account for 83% of aldicarb use.
Aldicarb Sulfoxide 0.001 0.004 none As the result of the aldicarb contamination of drinking
NOTE: The MCLs for aldicarb and its metabolites are waterwells, Union Carbide Corporation excluded the use
presently stayed °f aldicarb products in Suffolk County, Long Island, New
York. The company also limited the use of aldicarb
products to once every two years and only after plant
. co
HEALTH EFFECTS SUMMARY emergency in the States of Maine and Wisconsin and the
Acute: EPA has found aldicarb to potentially cause Counties of Hartford in Connecticut, Kent and New Castle
nausea, diarrhea and relatively minor neurological symp- in Delaware, Franklin and Hampshire in Massachusetts,
toms resulting from acute exposures at levels above the Worchesterin Maryland, Atlantic, Burlington, Cumberland,
MCL. These effects appear to be rapidly and completely Monmouth and Salem in New Jersey, Newport and
reversible after exposure. No Health Advisories have Washington in Rhode Island, and Accomack and
been established for short-term exposures. Northampton in Virginia.
Chronic: Aldicarb has the potential to cause neuro- Aldicarb may be applied at planting at the 1 Ib active
logical effects such as sweating, pupillary constriction ingredient/acre rate for aphid control in the State of
and leg weakness from chronic exposure at levels above Maine.
the MCL. These effects are associated with the inhibition
of cholinesterase in blood and nerve tissue. RELEASE PATTERNS
Cancec Thereis inadequate evidence to state whether Re|ease of a,djcarb to the environment will occur due
or not either aldicarb onts metabolites have the potential to jts manufacture and use as a systemic insecticide,
to cause cancer from hfet.me exposures in drinking acaricide and nematocide for soil use.
water.
ENVIRONMENTAL FATE
USAGE PATTERNS
If aldicarb is released to the soil it should not bind to the
Aldicarb is applied to the soil for control of chewing & soj, |t wi,| be susceptible to chemical and possibly bio-
sucking insects (aph.ds, whitefl.es, leaf miners, soil- logical oxidation to form its metabolites, aldicarb sulfox-
dwelling insects), spider mites, and nematodes. It is used jde and a|djcarb su|fone Hydrolysis is both acid and base
in glasshouse & outdoor ornamentals, and on the follow- cataiyzed with examples of hydrolysis half-lives in soil at
October 1995 _ Technical Version Printed on Recycled Paper
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15 deg C of 9.9 days at pH 6.34 and 7.0, 23 days at pH
7.2, and 3240 days at pH 5.4. Half-lives in soil have been
reported to be 7 days in loam soil under field conditions,
a few days in green house soil; a general range of
persistence in soil of 1-15 days has been reported.
Aldicarb degraded faster in soil which had been previ-
ously treated with carbofuran.
If aldicarb is released to water it should not adsorb to
sediments or bioconcentrate in aquatic organisms. Aldi-
carb does not degrade in groundwater under aerobic
conditions unless relatively high pH (pH 8.5) exists;
reported half-lives in groundwater under anaerobic con-
ditions at pH 7.7-8.3 were 62-1300 days. Aldicarb has
been shown to be formed from aldicarb sulfoxide in
groundwater under aerobic conditions and under anaero-
bic conditions in groundwater to which glucose had been
added. Aldicarb may volatilize from soil with the rate of its
evaporation increasing with the rate of evaporation for
water.
Aldicarb may leach to the groundwater in some soils
where the rates of hydrolysis and oxidation,are relatively
slow, as in the slow hydrolysis of aldicarb reported at pH's
around 5.4. It will be subject to hydrolysis which is both
acid and base catalyzed with examples of half-lives of
131 days at pH 3.95 and 6 days at pH 8.85 at 20 deg C,
and 3240 days at pH 5.5 and 15 deg C.
No information on biodegradation in natural waters
was found. It is susceptible to photolysis when irradiated
at 254 nm, but may not be photolyzed by light >290 nm.
Volatilization from water should not be an important fate
process. Half-life is 5 days in lake and pond water.
If aldicarb is released to the atmosphere it will be
subject to reaction with hydroxyl radicals with an esti-
mated vapor phase half-life of 3.49 days. No information
on photolysis at environmentally significant wavelengths
was found.
The propensity of aldicarb for bioaccumulation and
biomagnification was tested in a model ecosystem with a
terrestrial-aquatic interface and a seven-element food
chain. Aldicarb was shown to have a high degree of
persistence and a low potential for biodegradability.
A BCF of 42 for an unspecified species of fish in a
microcosm study has been reported. A BCF of 4 has
been estimated from water solubility. Based on the re-
ported and estimated BCF, aldicarb should not biocon-
centrate in aquatic organisms.
OTHER REGULATORY INFORMATION
NOTE: The MCLs for aldicarb and its. metabolites
are presently stayed. Systems must monitor for
these contaminants by December 31, 1995.
MONITORING:
FOR GROUND/SURFACE WATER SOURCES:
INITIAL FREQUENCY- 4 quarterly samples
REPEAT FREQUENCY- none
TRIGGERS - none
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:
4 EPA can provide further regulatory and other general information:
• EPA Safe Drinking Water Hotline - 800/426-4791
* Other sources of lexicological 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
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