|Chemical Abstract Number (CAS #)||
|Synonyms||Carbophenothion||Trithion||Phosphorodithioic acid, S-(((p-chlorophenyl)thio) methyl) O,O-diethyl ester
||EPA Method 617||EPA Method 8141
Link to the National Library of Medicine's Hazardous Substances
Database for more details
on this compound.
|Use|| Carbophenothion is a non-systemic acaricide and insecticide with a long residual action. It is
used in combination with petroleum oil, as a spray to control overwintering aphids, mites and
scale insects on dormant deciduous fruit trees; and as an acaricide on citrus trees and cotton; in
combination with parathion-methyl as a spray to control mites on grapevines, also with sulfur
against mildew oidium species; in combination with mevinphos to control mites on top fruit; as a
seed treatment against Debia coarctata on wheat.
Effectiveness of different insecticides against first and second instar nymphs and gravid females of
Drosicha mangiferae was studied under laboratory as well as field conditions. Carbophenothion at
0.05% gave 100% kill of first-instar nymphs of the pest. Out of 24 insecticides screened against
gravid females under laboratory conditions, carbophenothion at 0.025%, was found very effective.
Under field conditions, carbophenothion at 0.05% was found to be most effective against gravid
females of Drosicha mangiferae.
Non-systemic insecticide and acaricide with contact and stomach actions.
|Consumption Patterns|| 80% AS AN INSECTICIDE & ACARICIDE ON CITRUS CROPS; 20% AS AN
INSECTICIDE & ACARICIDE PRINCIPLY ON DECIDUOUS FRUITS & NUTS, BUT ALSO
ON ALFALFA & CLOVER, VEGETABLES, COTTON, SORGHUM, ORNAMENTALS,
TREES & SHRUBS, & AS AN ACARICIDE ON FIELD & SWEET CORN (1974)
|Apparent Color|| COLORLESS LIQ
|Odor|| MERCAPTAN-LIKE ODOR
|Boiling Point|| 82 DEG C @ 0.01 MM HG
|Molecular Weight|| 342.85
|Density|| 1.271 @ 25 DEG C/4 DEG C
|Environmental Impact|| Carbophenothion is released to the environment during its use as a miticide and an
insecticide. If released to the atmosphere, carbophenothion is expected to exist in the vapor and
particulate phases. Vapor-phase carbophenothion is expected to rapidly degrade by reaction with
photochemically produced hydroxyl radicals (estimated half-life of 1.6 hrs). If released to water,
hydrolysis may be the primary fate process of carbophenothion; however, no rate data under
environmental conditions (pH 5-9) were located. Carbophenothion absorbs little light above 290
nm and no light above 310 nm suggesting that photolysis will not be an important fate process.
Adsorption to sediment (measured Kocs of 45,400 and 46,800) and bioconcentration in aquatic
organisms will be important (BCF range of about 800 to 6,600). Insufficient data are available to
predict the importance of biodegradation in water or soil. In soil, slight mobility may occur and
photodegradation on soil surfaces may occur. Exposure of the general population to
carbophenothion is expected to occur through consumption of contaminated foods. In
occupational settings, exposure to carbophenothion may occur through inhalation and through
eye and skin contact.
|Environmental Fate|| TERRESTRIAL FATE: Hydrolysis may be important in moist soils(1,SRC); however, no
rate data under environmental conditions (pH 5-9) were located. Adsorption to soil (measured
Kocs of 45,400 and 46,800 ) may be important and slight mobility may occur .
Carbophenothion absorbs little UV light >290 nm and none above 310 nm in hexane solution
suggesting that little carbophenothion on soil surfaces may photodegrade. Insufficient data
are available to predict the importance of biodegradation in soil. One study suggests that
4-methyl-m-cresol and dimethyl-o-thiophosphoric acid are decomposition products of
carbophenothion in water(6) and these products may be found in soil. Carbophenothion
was qualitatively identified in surface soil samples collected from Tuscaloosa, Co., Pickens Co.
and Greene Co., Alabama(8). Dislodgeable residues of carbophenothion were identified 1-28 days
postapplication (January 24, 1983) at a concn range of 0.8 to 17.2 ppm on soil samples taken
midway between trees in an orange grove in Florida(7). In the same study, residues were identifed
1-28 days postapplication (January 24, 1983) at concns ranging from 0.06 to 26.6 ppm on soil
samples taken at the dripline(7).
AQUATIC FATE: One study suggests that 4-methyl-m-cresol and dimethyl-o-thiophosphoric
acid are decomposition products of carbophenothion in water . Hydrolysis may be the primary
fate process of carbophenothion in water ; however, no rate data under environmental
conditions (pH 5-9) were located. Adsorption to sediment (measured Kocs of 45,400 and
46,800 ) and bioconcentration in aquatic organisms will be important (BCF range of about 800
to 6,600(4,SRC)). Untreated and sterile sediment water systems retained 57% after 5 days and
51% after 7 days, respectively, suggesting that biological processes are not responsible for the
degradation of carbophenothion ; however, insufficient data are available to predict the
importance of biodegradation in aquatic systems. Volatilization from water will not be
important based on an estimated Henry's Law constant of 2.15X10-7 atm-cu m/mole at 20 deg
ATMOSPHERIC FATE: Based on a measured vapor pressure of 3X10-7 mm Hg at 20 deg C ,
carbophenothion is expected to exist in both the vapor and particulate phases in the ambient
atmosphere . Vapor phase carbophenothion in the ambient atmosphere is rapidly degraded by
reaction with photochemically formed hydroxyl radicals; the half-life for this reaction in air can be
estimated to be about 1.6 hrs(1,SRC).