Diphenamid (ISO)

Pesticide -> EPA IRIS

Herbicides

Active substance -> EU Pesticides database: Not approved

Pesticides -> Herbicides, Other

Pesticide (Diphenamid) -> USDA PDB

Pesticide

Log P: 2.17

2.17

1.17 @ 23.3 °C

1.2 g/cm³

WHITE

CRYSTALS FROM ETHYL ACETATE

WHITE PRISMS

Colorless

SOLUBILITY (G/100 ML SOLVENT @ 27 °C): 18.9 IN ACETONE, 16.5 IN N,N-DIMETHYLFORMAMIDE, 32.0 IN PHENYL CELLOSOLVE, 0.026 IN WATER, 5.01 IN XYLENE

water solubility = 260 mg/l @ 27 °C

Solubility in water, g/100ml at 27 °C: 0.03

134.5 TO 135.5 °C

MP: 128-135 °C (TECHNICAL PRODUCT 95% PURE)

135 °C

0.00000003 [mmHg]

3.00X10-8 mm Hg @ 25 °C

Diphenamid appears as colorless to off-white crystals. Used as an herbicide.

White solid; [Hawley] Colorless or white solid; Technical product: Off-white solid; [HSDB]

WHITE SOLID IN VARIOUS FORMS.

Warning

H302: Harmful if swallowed [Warning Acute toxicity, oral]

P264, P270, P273, P301+P317, P330, and P501 (click each P-code to see the statement)

Warning

H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]

P264, P270, P273, P301+P317, P330, and P501 (click each P-code to see the statement)

No listed effects of short-term or long-term exposure; [ICSC] Causes convulsions in high-dose animal experiments; No effects in rats fed 10 mg/kg for 90 days; Non-irritant and non-sensitizer of skin in animal tests; [HSDB] An irritant; [MSDSonline]

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Diphenamid is found on List A, which contains most food use pesticides and consists of the 194 chemical cases (or 350 individual active ingredients) for which EPA issued registration standards prior to FIFRA, as amended in 1988. Case No: 0269; Pesticide type: Herbicide; Registration Standard Date: 06/30/87; Case Status: No products containing the pesticide are actively registered ... The case /is characterized/ as "cancelled." Under FIFRA, pesticide producers may voluntarily cancel their registered products. EPA also may cancel pesticide registrations if registrants fail to pay required fees or make/meet certain reregistration commitments, or if EPA reaches findings of unreasonable adverse effects.; Active ingredient (AI): Diphenamid; AI Status: The active ingredient is no longer contained in any registered pesticide products ... "cancelled."

Tolerances are established for residues of the herbicide diphenamid (N,N-dimethyl-2,2-diphenylacetamide) including its desmethyl metabolite (N-methyl-2,2-diphenylacetamide) in or on raw agricultural commodities as follows: peanut hay and forage; potatoes and strawberries; peanut hulls and soybean hay and forage; cotton forage; apples, cottonseed, fruiting vegetables, okra, peaches, peanuts, soybeans, and sweet potatoes; meat, fat, and meat byproducts of cattle, goats, hogs, horses, and sheep; milk; and rasberries.

DIPHENAMID is an amide. Amides/imides react with azo and diazo compounds to generate toxic gases. Flammable gases are formed by the reaction of organic amides/imides with strong reducing agents. Amides are very weak bases (weaker than water). Imides are less basic yet and in fact react with strong bases to form salts. That is, they can react as acids. Mixing amides with dehydrating agents such as P2O5 or SOCl2 generates the corresponding nitrile. The combustion of these compounds generates mixed oxides of nitrogen (NOx). This compound is decomposed by strong base or acid.

Acute Tox. 4 (100%)

Acute toxicity - category 4

Acute Tox. 4 *

Fresh air, rest.

Rinse and then wash skin with water and soap.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Induce vomiting (ONLY IN CONSCIOUS PERSONS!). Refer for medical attention .

Recommendable method: Incineration. Peer-review: Large amt of diphenamid should be burned in incinerator with effluent gas scrubbing when well diluted with other wastes. Solid material can be dissolved in acetone or xylene to ease feeding into incinerator. (Peer-review conclusions of an IRPTC expert consultation (May 1985))

Hydrolysis: Alkali hydrolysis: Slow reaction. Phenylacetic acid and dimethylamine are less phytotoxic.

Tolerances are established for residues of the herbicide diphenamid (N,N-dimethyl-2,2-diphenylacetamide) including its desmethyl metabolite (N-methyl-2,2-diphenylacetamide) in or on raw agricultural commodities as follows: 2 ppm in or on peanut hay and forage; 1 ppm in or on potatoes and strawberries; 0.5 ppm in or on peanut hulls and soybean, hay and forage; 0.2 ppm in or on cotton forage; 0.1 ppm (negligible residue) in or on apples, cottonseed, fruiting vegetables, okra, peaches, peanuts, soybeans, and sweet potatoes; 0.05 ppm (negligible residue) in meat, fat, and meat byproducts of cattle, goats, hogs, horses, and sheep; 0.01 ppm (negligible residues) in milk; and 1.0 ppm in or on rasberries.

EC50 DAPHNIA MAGNA 58 MG/L/48 HR, IMMOBILIZATION (95% CONFIDENCE LIMIT 43-79 MG/L) AT 21 °C, 1ST INSTAR. STATIC BIOASSAY WITHOUT AERATION, PH 7.2-7.5, WATER HARDNESS 40-50 MG/L AS CALCIUM CARBONATE AND ALKALINITY OF 30-35 MG/L.

EC50 CYPRIDOPSIS VIDUA 51 MG/L/48 HR, IMMOBILIZATION (95% CONFIDENCE LIMIT 37-71 MG/L) AT 21 °C, MATURE. STATIC BIOASSAY WITHOUT AERATION, PH 7.2-7.5, WATER HARDNESS 40-50 MG/L AS CALCIUM CARBONATE AND ALKALINITY OF 30-35 MG/L.

LC50 ASELLUS MORE THAN 100 MG/L/96 HR AT 15 °C, MATURE. STATIC BIOASSAY WITHOUT AERATION, PH 7.2-7.5, WATER HARDNESS 40-50 MG/L AS CALCIUM CARBONATE AND ALKALINITY OF 30-35 MG/L.

LC50 GAMMARUS FASCIATUS MORE THAN 100 MG/L/96 HR AT 15 °C, MATURE. STATIC BIOASSAY WITHOUT AERATION, PH 7.2-7.5, WATER HARDNESS 40-50 MG/L AS CALCIUM CARBONATE AND ALKALINITY OF 30-35 MG/L.

For more Ecotoxicity Values (Complete) data for DIPHENAMID (7 total), please visit the HSDB record page.

TERRESTRIAL FATE: Diphenamid has an estimated Koc of 210(3) and therefore would be expected to leach moderately in soil. Biodegradation is the primary degradative pathway for loss of diphenamid from soils(1-2). The persistence of diphenamid in soil will depend on the soil type, moisture content and the temperature of soil(2). Under warm, moist conditions, the average persistence of diphenamid after application at recommended rates is 3-6 months(2). At higher application rates and under low rainfall or colder temperatures, diphenamid may persist in soil longer than 6 months(5-6). The rate of biodegradation increases moderately in soils that have been previously treated with diphenamid. Diphenamid is non volatile and appears to be stable in sunlight(2).

AQUATIC FATE: Neither hydrolysis(1-2) nor photolysis by sunlight(3-4) should be important for the degradation of diphenamid in water. Based on its ability to undergo biodegradation in soil(5), biodegradation should be the most important process for diphenamid in water(SRC). A Koc value of 210(6) indicates that diphenamid may be moderately adsorbed to suspended solids and sediment in water(SRC). The estimated BCF value of 27(6) indicates that bioconcentration of diphenamid in aquatic organisms will not be important(SRC).

ATMOSPHERIC FATE: Based on a vapor pressure of 3X10-8 mm Hg(1), diphenamid should be present mostly in the particulate form in air, but a small amount may be present in the vapor phase(2,SRC). Based on an estimation method(3), vapor phase diphenamid may be removed from the atmosphere with a half-life of 10.6 hrs due to reaction with photochemically produced hydroxyl radicals(SRC). Partial removal of particulate diphenamid from the air may occur by dry deposition(SRC). Both vapor and particle phase diphenamid may be partly removed from the atmosphere by wet deposition.

Diphenamid

Hepatic

3 x 10 ^-2 mg/kg-day

DIPHENAMID IS NOT TIGHTLY ADSORBED ON SOIL COLLOIDS. IT LEACHES RAPIDLY IN SANDYSOILS BUT SLOWLY IN LOAM OR CLAY SOILS. IN SANDY SOILS, RETENTION OF AN EFFECTIVE CONCN IN THE WEED SEED GERMINATION ZONE WITH HEAVY RAINFALL CAN BE A PROBLEM.

A Koc of 210 for diphenamid has estimated from its water solubility(1-2). According to a suggested classification scheme, this Koc value indicates that diphenamid would be moderately mobile in soil(5). Soil thin layer chromatography studies indicates that the average retention factor (Rf) of diphenamid in a silty loam soil is 0.49(3-4). This Rf value also indicates that diphenamid has moderate mobility in soil(3).

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Diphenamid is found on List A, which contains most food use pesticides and consists of the 194 chemical cases (or 350 individual active ingredients) for which EPA issued registration standards prior to FIFRA, as amended in 1988. Case No: 0269; Pesticide type: Herbicide; Registration Standard Date: 06/30/87; Case Status: No products containing the pesticide are actively registered ... The case /is characterized/ as "cancelled." Under FIFRA, pesticide producers may voluntarily cancel their registered products. EPA also may cancel pesticide registrations if registrants fail to pay required fees or make/meet certain reregistration commitments, or if EPA reaches findings of unreasonable adverse effects.; Active ingredient (AI): Diphenamid; AI Status: The active ingredient is no longer contained in any registered pesticide products ... "cancelled."

Tolerances are established for residues of the herbicide diphenamid (N,N-dimethyl-2,2-diphenylacetamide) including its desmethyl metabolite (N-methyl-2,2-diphenylacetamide) in or on raw agricultural commodities as follows: peanut hay and forage; potatoes and strawberries; peanut hulls and soybean hay and forage; cotton forage; apples, cottonseed, fruiting vegetables, okra, peaches, peanuts, soybeans, and sweet potatoes; meat, fat, and meat byproducts of cattle, goats, hogs, horses, and sheep; milk; and rasberries.

(CA) CALIFORNIA 200 ug/l

(FL) FLORIDA 210 ug/L

HALF-LIVES FOR (14)C IN BLOOD OF RATS DOSED WITH (14)C-DIPHENAMID ... BY ORAL, IP, & SC ROUTES WERE SIMILAR (ABOUT 4 HR). HOWEVER, BLOOD LEVELS OF (14)C ... GREATER @ PEAK ABOUT 50 MIN AFTER IP DOSING THAN @ PEAK ABOUT 200 MIN AFTER DOSING BY OTHER TWO ROUTES.

The metabolism of diphenamid in cell suspensions of soybeans was studied. When (l4)C-carbonyl-labeled diphenamid was added to the suspensions, the major products were identified as N-hydroxymethyl N-methyl-2,2-diphenylacetamide, N-methyl-2,2-diphenylacetamide, 2,2-diphenylacetamide, an unidentified glucoside, and an acidic conjugate of glucose, malonate and diphenamid.

In cotton, okra, peanut shoots, and soybean shoots, dealkylated products and water-soluble compounds were present. Brightleaf and burley tobacco shoots also had dealkylated products. In cotton, okra, peanut and soybean shoots, the presence of the glucoside and gentiobioside were observed.

Aquatic plants and algae were exposed to diphenamid in trays and jars. The vascular plants and aquatic algae absorbed and removed diphenamid from the water. In algae, water hyacinth, and parrotfeather, N-methyl-2,2-diphenylamide and other unidentified materials were observed.

METABOLISM ... IN CORN ROOTS ... WITH CARBONYL (14)C LABELING. ONLY CMPD IDENTIFIED ... N-METHYL-2,2-DIPHENYLACETAMIDE.

For more Metabolism/Metabolites (Complete) data for DIPHENAMID (14 total), please visit the HSDB record page.

DIPHENAMID ... IS WELL ABSORBED & READILY METABOLIZED IN MAMMALS.

STUDIES WITH POSTEMERGENCE TREATMENTS ON CROPS OR WEEDS INDICATE ONLY A LOW LEVEL OF FOLIAR ABSORPTION. ... /IT/ IS ABSORBED VIA THE ROOTS AND TRANSLOCATED THROUGH THE ROOTS, STEM, & LEAVES.

TOMATO PLANTS (LYCOPERSICON ESCULENTUM MILL, VARIETY SHEYENNE), 27-35 DAYS OLD ... FUMIGATED WITH OZONE PRIOR TO EXPOSING ... ROOTS TO (14)C DIPHENAMID ... DIFFERENCES ... OBSERVED: 1. FUMIGATED PLANTS ABSORBED 70-100% AS MUCH DIPHENAMID AS DID CONTROLS, 2. FUMIGATED PLANTS ... CONTAINED LESS RADIOACTIVITY IN CHCL3-SOL FRACTION ... .

URINARY EXCRETION /BY RATS DOSED WITH (14)C-DIPHENAMID/ OF (14)C WAS FAIRLY RAPID AFTER IP DOSE; 51% WAS PRESENT IN 22 HR URINE & 89% IN 46 HR. THESE RESULTS INDICATED THAT THIS LIPID-SOL UNIONIZED CMPD WAS READILY ABSORBED IN RATS.

For more Absorption, Distribution and Excretion (Complete) data for DIPHENAMID (6 total), please visit the HSDB record page.

Used as pre-emergence herbicide for control of annual grasses and broad-leaved weeds in cotton, potatoes, vegetables, soy beans, tobacco, fruits, forestry nurseries, and ornamentals; Also used as plant growth regulator; Discontinued in 1988 by NOR-AM Chemical Co.; [HSDB]

Cancelled--no longer registered as a pesticide for use in the US; [HSDB]

Farming (Pesticides) [Category: Industry]

The active ingredient is no longer contained in any registered pesticide products ... "cancelled."

HERBICIDE FOR CONTROL OF ANNUAL BROADLEAF WEEDS & ANNUAL GRASSES.

SELECTIVE PREEMERGENCE HERBICIDE THAT CONTROLS GRASSES & BROADLEAF WEEDS SUCH AS CARPETWEED, CHICKWEED, KNOTWEED, LAMBSQUARTERS, PIGWEED, PURSLANE, & SMARTWEED.

REACTION OF DIPHENYL ACETYL CHLORIDE WITH DIMETHYLAMINE IN THE PRESENCE OF A BASE

... BY REACTION OF DIPHENYLMETHANE & DIMETHYLCARBAMOYL CHLORIDE IN PRESENCE OF SODIUM HYDRIDE ... .

AVAILABLE IN 50 & 80% WETTABLE POWDERS; 4 LB/GAL LIQ DISPERSION, & 5% GRANULES. COMBINATIONS: AVAILABLE AS MIXT OF TREFLAN & DYMID, KNOWN AS TREFMID.

'ENIDE 90W', WP (900 G AI/KG); 'ENIDE 50W', WP (500 G AI/KG);

LAB METHOD OF PURIFICATION: CRUDE PRODUCT CAN BE RECRYSTALLIZED FROM ETHYL ACETATE AND HEXANE OR ETHYL ACETATE ALONE.

... INTRODUCED IN 1960, AS HERBICIDE BY ELI LILLY & CO, UNDER CODE NUMBER "L-34314" & TRADE MARK "DYMID", ALSO "ENIDE" (UPJOHN CO). IT WAS FIRST DESCRIBED AS HERBICIDE BY ALDER, EF ET AL, PROC NC WEED CONTROL CONF, 1960, P 55 & IS PROTECTED BY USP 3,120,434.

TOLERANT CROPS INCL PEANUT, TOMATOES, PEPPERS, IRISH POTATOES, SWEET POTATOES, STRAWBERRIES, APPLE TREES, ORANGE & LIME TREES, SOYBEANS, COTTON, OKRA, TRANSPLANT CABBAGE, DICHONDRA, WOODY ORNAMENTALS ... CEREAL GRAINS ARE SENSITIVE TO ... /IT/ ... SURFACE-APPLIED ... LIGHT RAINFALL OR SPRINKLER IRRIGATION FOLLOWING DIPHENAMID APPLICATION WILL IMPROVE ITS CONTROL OF WEEDS. UNDER CONDITIONS OF DRY WEATHER, FOLLOWING APPLICATION OF DIPHENAMID, SOIL INCORPORATION MAY INCREASE THE EFFICACY OF THE HERBICIDE. DIPHENAMID MAY BE APPLIED IMMEDIATELY AFTER SEEDING THE CROP OR OVER TOP OF TRANSPLANT CROPS ANY TIME AFTER TRANSPLANTING BUT PRIOR TO WEED EMERGENCE. ON PEANUTS DIPHENAMID MAY BE APPLIED AT PLANTING, AT CRACKING, OR UP TO 7 DAYS AFTER CRACKING; WITH THE LATTER TWO APPLICATIONS, DIPHENAMID SHOULD BE COMBINED WITH DINOSEB AMINE. ... RATES: 2.0-6.0 LB/ACRE ... DIPHENAMID WETTABLE POWDER IS NOT SIGNIFICANTLY INFLUENCED IN ITS SPRAYABILITY BY WATER HARDNESS.

Discontinued in 1988 by NOR-AM Chemical Co.