Diflubenzuron

310.68

310.68

252-529-3

J76U6ZSI8D

3077|2588

DTXSID1024049

Colorless crystals

2924299031

58.2

3.88

Solid

1.57 at 20 deg C

239 °C

BP: 257 °C at 300 mm Hg

H2O: 0.008 g/100 mL;Almost insoluble in apolar solvents. Moderate to good solubility in most polar-to-very polar solvents.

0-6°C

1.2 x l0 -4 mPa (25 °C)

LD50 in mice, rats (formulation with 50% kaolin) (g/kg): 4.64, >10 orally (Mulder, Gijswijt)

Henry's Law constant = 4.6X10-9 atm-cu m/mol at 25 °C (est)

160.98 Ų [M+H]+ [CCS Type: TW]|161.73 Ų [M+H]+

Decomposes on distillation|In aqueous solution (20 °C), stable at pH 5 and pH 7 (half-life > 180 days); at pH 9, half-life of 32.5 days|Hydroxyl radical reaction rate constant = 1.6X10-11 cu cm/molec-sec at 25 °C (est)

Hydrolyzed in alkaline solution above pH 9.0.

Amides and Imides

A urea derivative.

Non-corrosive

III

9

3077

2

50/53

60-61

YS6200000

C,N

Under conditions approximating normal use, diflubenzuron was persistent on cotton plants and resistant to photodecomposition.

P273, P280, P302+P352, P312, P322, P363, P391, P501

H312

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Diflubenzuron hydrolyzes in water to p-chlorophenylurea.

WHO; DIFLUBENZURON HEALTH AND SAFETY GUIDE (1995)[WHO; DIFLUBENZURON HEALTH AND SAFETY GUIDE (1995); Available from, as of March 13, 2014: http://www.inchem.org/documents/hsg/hsg/hsg099.htm]|USEPA/Office of Prevention, Pesticides and Toxic Substances; Reregistration Eligibility Decision Document - Diflubenzuron, EPA 738-R-97-008 (August 1997). The RED summarizes the risk assessment conclusions and outlines any risk reduction measures necessary for the pesticide to continue to be registered in the U.S.[Available from, as of February 12, 2014: http://www.epa.gov/pesticides/reregistration/status.htm]

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Some may burn but none ignite readily. Containers may explode when heated. Some may be transported hot. For UN3508, be aware of possible short circuiting as this product is transported in a charged state. (ERG, 2016)

|Warning|H312 (81.85%): Harmful in contact with skin [Warning Acute toxicity, dermal]|P273, P280, P302+P352, P312, P322, P363, P391, and P501|Aggregated GHS information provided by 292 companies from 17 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|H401: Toxic to aquatic life [Hazardous to the aquatic environment, acute hazard]|P273, P391, and P501

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. SPILL: Increase, in the downwind direction, as necessary, the isolation distance shown above. FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2016)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent dust cloud. Avoid inhalation of asbestos dust. SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area. SMALL SPILL: Pick up with sand or other non-combustible absorbent material and place into containers for later disposal. LARGE SPILL: Dike far ahead of liquid spill for later disposal. Cover powder spill with plastic sheet or tarp to minimize spreading. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2016)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection. (ERG, 2016)|Safety glasses with side-shields conforming to EN166 Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).|For nuisance exposures use type P95 (US) or type P1 (EU EN 143) particle respirator.For higher level protection use type OV/AG/P99 (US) or type ABEK-P2 (EU EN 143) respirator cartridges. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).|Complete suit protecting against chemicals, The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.|Handle with gloves. Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.

Wear self contained breathing apparatus for fire fighting if necessary.|Fire Extinguishing Media: Water spray, dry chemical.

Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Avoid breathing dust.|Collect spill to prevent product from entering sewage system.

Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Provide appropriate exhaust ventilation at places where dust is formed. Normal measures for preventive fire protection.|SRP: The scientific literature for the use of contact lenses by industrial workers is inconsistent. The benefits or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

Diflubenzuron is neither a skin irritant ...nor a skin sensitizer... It is marginally irritant to the eyes...

Wastewater influent, effluent and sludge from 25 facilities in 18 US States were analyzed for various biocides, pesticides and degradates including diflubenzuron(1); concentrations of diflubenzuron were below the limit of detection in all matrices(1).

SOIL: Dislodgeable residues of diflubenzuron were identified 1 and 29 days post-application (March-April, 1978) at respective concentrations of 0.35 and 0.14 ppm on soil samples taken midway between trees in an orange grove in Florida. In the same study, residues were identified 1 and 29 days post-application at respective concentrations of 2.68 and 1.07 ppm on soil samples taken at the drip line(1).

Although the toxins of Bacillus thuringiensis Berliner (Bt) are frequently used to control lepidopteran pests, the tolerance or resistance of some lepidopteran moth strains may limit Bt applications. In this study, insecticidal cocktails consisting of sublethal doses of Cry1Ab toxin and additive compounds were tested for their suppressive effect on larval relative growth rate (RGR) in Ephestia kuehniella Zeller under laboratory conditions. In the first step, the suppressive effect of diflubenzuron, soybean trypsin inhibitor (STI) and chitinase on RGR was confirmed. In the second step, these compounds were incorporated into a mixture of crushed kernels of Bt maize hybrid MON 810-YieldGard and its isoline with concentrations of Cry1Ab toxin ranging from 0.011 to 0.091 ug/g diet. An additive effect on the suppression of larval RGR in E. kuehniella was found in a combination of diflubenzuron, STI and STI + chitinase as secondary compounds in insecticidal cocktails. Chitinase showed no additive effect on RGR. The highest suppression level was found in cocktails with STI + chitinase as a secondary compound. It is hypothesized that the protease inhibitor (STI) protects both chitinase and Cry1Ab proteins from endogenous proteases in the larval midgut and prolongs their insecticidal activities. The possible application of insecticidal cocktails in the control of E. kuehniella is discussed.|Aedes aegypti mosquito is one of the most notorious vectors of dangerous diseases like dengue hemorrhagic fever and chikangunya. One method of control of the vectors is by the use of semiochemicals or pheromones. The pheromone n-heneicosane (C21) has been proved to be effective in attracting the female Aedes aegypti to lay eggs in the treated water and the growth of the larva is controlled by insect growth regulator diflubenzuron (DB). This study was planned to assess the safety of C21 alone and the combination with DB. Acute toxicity tests were carried out using two doses, viz., 1600 and 3200 mg/kg and two routes of exposure oral and intra-peritoneal. Dermal toxicity test was carried out in both male and female rats at the dose of 3200 mg/kg. Primary skin irritation test was carried out in rabbits. Sub-acute (90 days) dermal toxicity studies in male and female rats at the dose of 1 and 2 mg/kg via the per-cutaneous route were also studied. Sub-acute (90 days) toxicity test through the oral route was carried out, at doses 125, 250 and 500 mg/kg in male and female rats. The calculated LD50 by ip route and dermal route was more than 5 g/kg in mouse and rats of both the sexes. In the primary skin irritation test no significant changes were noted. In the sub-acute toxicity studies even 500 mg/kg dose was not able to produce toxic response in rats when they were dosed daily for 90 days. The established no observed adverse effect level (NOAEL) was more than 500 mg/kg.

LD50 Rat oral > 4640 mg/kg|LD50 Mouse oral 4.64 g/kg /Formulation with 50% kaolin/|LD50 Rat oral > 10 g/kg /Formulation with 50% kaolin/|LD50 Rabbit ip 1040 mg/kg|For more Non-Human Toxicity Values (Complete) data for DIFLUBENZURON (15 total), please visit the HSDB record page.

/BIRDS and MAMMALS/ Toxicity to mammals and birds is low (LD50 values in the range of 4500 to 10,000 mg/kg).|/BIRDS and MAMMALS/ A 5-day dietary study on the mallard duck and bobwhite quail with levels of up to 4640 mg/kg did not reveal any observable signs of toxicity. Small songbirds in the forest ecosystem were not affected after aerial application of diflubenzuron at 350 g/ha. Small mammal species in a forest did not show any reductions in numbers after application of diflubenzuron at 67 g/ha.|/AQUATIC SPECIES/ Increasing use of the chitin synthesis inhibitor diflubenzuron against the ectoparasitic salmon louse Lepeophtheirus salmonis in marine aquaculture has raised concerns over its environmental impacts. This study evaluated how diflubenzuron affects Atlantic cod Gadus morhua, a fish species often found near Atlantic salmon Salmo salar farms, focusing on uptake kinetics and hepatic transcriptional responses. Two experiments were conducted, one time-series trial in which the fish were given a daily dose (3 mg/kg fish) of diflubenzuron for 14 d followed by a 3 wk depuration period, and one dose-response trial with increasing concentrations (3, 10 and 50 mg/kg fish). The highest diflubenzuron concentrations were found in the liver at Day 15. No detectable levels of diflubenzuron were found in liver or muscle 3 wk after the end of the treatment. At the molecular level, small effects of diflubenzuron treatment on gene transcription were observed. In the time-series experiment, the strongest effects were seen at Day 8, with 2 transcripts being upregulated (bclx2 and cpt1a) and 8 transcripts being downregulated (gstp1, gstm1, gstt1, ugt1a, nat2, cat, p53 and slc16a9a). Five transcripts (cyp3a, cpt1a, ptgs2, elovl5 and mapk1) responded significantly to diflubenzuron exposure in the dose-response experiment. This study shows that diflubenzuron can be taken up by Atlantic cod, that it is rapidly cleared from the body and that when present this pharmaceutical causes only small effects on the expression of genes involved in detoxification pathways. Taken together, our data suggest that accumulated diflubenzuron at the levels studied would have a relatively small effect on wild Atlantic cod.|/AQUATIC SPECIES/ The effects of diflubenzuron (DFB), an insecticide to control ectoparasites in fish farms, on muscle acetylcholinesterase (AChE), detoxifying and antioxidant enzymes, hematological and physiological parameters, and liver histopathology were evaluated in Prochilodus lineatus after 6, 24 and 96 hr of exposure to 25 mg/L of DFB. The insecticide caused a reduction in the number of erythrocytes and hemoglobin content after 96 hr exposure, probably due to hemolysis. Hyperglycemic response indicated energy mobilization, and may have contributed to the increase in osmolarity after 96 hr exposure to DFB. The induction of glutathione-S-transferase (GST) and catalase activities in liver pointed to the activation of xenobiotic metabolic pathways and antioxidant defenses. The decrease in muscle AChE at all experimental times showed that DFB is an AChE inhibitor. In addition, DFB induced hepatic alterations that might impair normal liver functions. These results show that DFB can cause health disorders in fish and further studies are required to better define its safe use in aquaculture.|For more Ecotoxicity Excerpts (Complete) data for DIFLUBENZURON (13 total), please visit the HSDB record page.

The diflubenzuron metabolite, 4-chloroaniline, has been reported to cause methemoglobinemia in exposed workers and in neonates inadvertently exposed. Some individuals who are deficient in NADH-methemoglobin reductase may be particularly sensitive to 4-chloroaniline and, hence, to diflubenzuron exposure.

Diflubenzuron's production may result in its release to the environment through various waste streams; its use as an insecticide(1) will result in its direct release to the environment(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values of 6,790 and 10,600(2) indicate that diflubenzuron is expected to be immobile in soil(SRC). Volatilization of diflubenzuron from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.6X10-9 atm-cu m/mole(SRC), calculated from its vapor pressure of 9X10-10 mm Hg(3) and water solubility of 0.08 mg/L(3). Diflubenzuron is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure. In photodegradation tests on soil surfaces, diflubenzuron has a reported half-life of 11.3 days(2). Microorganisms play a major role in the disappearance of diflubenzuron from soil(4,5). Field dissipation half-lives are reported to range from 2 to 35 days(2). Bare ground dissipation half-lives range from 5.8-13.2 days with half-lives as high as 68.2-78 days in citrus and apple orchards(5). An apparent half-life of 30 days was observed in a forestry study(5).|AQUATIC FATE: Based on a classification scheme(1), a Koc values of 6,790 and 10,600(2) indicate that diflubenzuron is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 4.6X10-9 atm-cu m/mole(SRC), derived from its vapor pressure of 9X10-10 mm Hg(4) and water solubility of 0.08 mg/L(4). According to a classification scheme(5), bluegill sunfish BCF values of 34-200 for fillet and 78-360 for whole fish(6) suggest the potential for bioconcentration in aquatic organisms is moderate to high(SRC). The hydrolysis half-life of diflubenzuron at pH 5 and pH 7 is >180 days at 25 °C(7); at pH 9, the hydrolysis half-life is 32.5 days(7). The direct photolysis half-life of diflubenzuron in aqueous solution under natural sunlight conditions at 40 deg N latitude is reported to be 80 days(7). Much faster photodegradation half-lives have been observered using river water(8) suggesting diflubenzuron may be susceptible to photo-sensitized photolysis(SRC). Biodegradation half-lives averaged between 14 and 32 days in screening tests using marine-sediment and marine-water(9), suggesting biodegradation is an important fate process in water(SRC). When incubated under flooded anaerobic conditions with a silt loam soil, diflubenzuron had a half-life of 34 days at 24 °C(6).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), diflubenzuron, which has a vapor pressure of 9X10-10 mm Hg at 25 °C(2) is expected to exist solely in the particulate phase in the ambient atmosphere. Particulate-phase diflubenzuron may be removed from the air by wet and dry deposition(SRC). Diflubenzuron has been shown to degrade through direct photolysis in sunlight(3,4) suggesting that photolysis may occur in the atmosphere(SRC).

The hydrolysis half-life of diflubenzuron at pH 5 and pH 7 was determined to be >180 days at 25 °C(1); at pHs 5 and 7, 90% remained unchanged after 4 weeks(2); at pH 9, the hydrolysis half-life was 32.5 days(1). Diflubenzuron (0.1 ppm) exhibited a 3-5% loss after 8 hr in tap water at 10 °C and pH 7.7-10; at 38 °C, a 4% loss was observed at pH 7.7 and a 22% loss was observed at pH 10 after 8 hr(3). At 24 °C, an average 10% loss was observed after 9 days for diflubenzuron in tap water at pH 7.7 and an average 27% loss was observed after 9 days at pH 10(3). The hydrolysis half-life of diflubenzuron in aqueous solution at 36 °C and pH 6 was reported as 7 days and at pH 10 was less than 3 days(4). The following 7 hydrolysis products were identified:(4-chlorophenyl)urea, 2,6-difluorobenzoic acid, 2,6-difluorobenzamide, 4-chloroaniline, N,N'-bis(4-chlorophenyl)urea, and a 2,4-quinazolinedione derivative that resulted from the expulsion of HF from diflubenzuron with cyclization at the anilino nitrogen and the ortho carbon of the benzoyl ring, and further reaction of the quinazolinedione compound(4). Using EPA guideline CG6000 and 40 days of continuous irradiation from a 450 W Xenon arc lamp, diflubenzuron had an estimated aqueous direct photolysis half-life of 80 days at 25 °C under natural sunlight conditions at 40 deg N latitude(1). In photodegradation tests on soil surfaces, diflubenzuron had reported half-lives of 11.3 and 3.7 days for light exposed and control samples, respectively(2); degradates included, p-chlorophenyl urea, 2,6-difluorobenzoic acid and 14-CO2(2). Diflubenzuron was resistant to photodecomposition when applied to cotton plants and illuminated with sunlight(5); however, diflubenzuron applied to glass films underwent 12% photodecomposition when illuminated with sunlight for 9 hours(3). In buffered deionized water irradiated with UV-light >290 nm, diflubenzuron had photolysis half-lives of 17 hours at pH 7 and 8 hours at pH 9(6). In a solar simulator using river water buffered to pH 9, diflubenzuron had a half-life of 12 hours with no loss of diflubenzuron in dark controls(6).

158.49|Reported bioconcentration factors for diflubenzuron in bluegill sunfish (Lepomis macrochirus) ranged from 34 to 200 for fillet and 78 to 360 for whole fish(1). According to a classification scheme(2), these BCF ranges suggest the potential for bioconcentration in aquatic organisms is moderate to high. Diflubenzuron depurates rapidly in fish tissue(1); the depuration rate indicates a rapid decrease (99%) of accumulated residues in tissue during a 14-day depuration period.

6.76e+03 L/kg|Diflubenzuron has reported Koc values of 6,790 and 10,600(1). According to a classification scheme(2), these Koc values suggest that diflubenzuron is expected to be immobile in soil. Binding to soil is an important transport process for diflubenzuron based on soil Kd values for sand clay, silty clay loam, silt loam, sand loam, sandy clay loam, clay, clay hydrosoil, and peat hydrosoil of 40, 40, 20, 25, 130, 110, 150, and 3500, respectively(3). Diflubenzuron is classified as relatively immobile in soil based on Rf values were 0.01, 0.07, 0.14, and 0.34 for silty clay loam, clay loam, and two sand loam soils, respectively(3). In field tests, diflubenzuron was not detectable below the 0-15 cm soil depth segment over a 60-day period(3). In water tank studies, diflubenzuron adsorbed to sediment showed no detectable diffusion from the sediment to water over a 204-day observation period(4).

The Henry's Law constant for diflubenzuron is estimated as 4.6X10-9 atm-cu m/mole(SRC) derived from its vapor pressure, 9X10-10 mm Hg(1), and water solubility, 0.08 mg/L(1). This Henry's Law constant indicates that diflubenzuron is expected to be essentially nonvolatile from water surfaces(2). Diflubenzuron's Henry's Law constant indicates that volatilization from moist soil surfaces is not expect to occur(SRC). Diflubenzuron is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1).

Dislodgeable residues of diflubenzuron were identified 1 and 29 days post-application (March-April, 1978) at respective concentrations of 0.40 and 0.32 ppm on the fruit in an orange grove in Florida(1). Dislodgeable residues of diflubenzuron were identified 1 and 29 days post-application (July-August, 1978) at respective concentrations of 0.18 and 0.07 ppm on the fruit in an orange grove in Florida(1). In a monitoring study in Valencia Spain where 150 orange fruit samples were collected between Sept 1998 and June 1999, diflubenzuron was detected in 20 samples and concentrations ranging from 0.003-1.8 mg/kg(2).

Following oral administration, diflubenzuron is absorbed, extensively metabolized, and almost totally excreted by cattle and sheep ... Trace amounts of the larvicide are excreted in milk following high dosages.

Occupational exposure to diflubenzuron may occur through inhalation of dust particles and dermal contact with this compound at workplaces where diflubenzuron is produced or used. The general population may be exposed to diflubenzuron via ingestion of food products containing diflubenzuron. Since diflubenzuron is sprayed aerially on forests, swamps or vegetation in order to inhibit mosquito or fly growth, the general population may also be exposed to this compound through inhalation and dermal contact with leaves or vegetation. (SRC)

Based on a pesticide residue study in oranges and an estimated annual intake of oranges of 22.26 kg/person, the estimated average daily intake of diflubenzuron is 0.042 ug/kg body wt/day(1).

The intestinal absorption is strongly related to the dosage administered - the higher the dosage, the more is (relatively) excreted unchanged in the feces.|Following oral administration, diflubenzuron is absorbed, extensively metabolized, and almost totally excreted by cattle and sheep ... Trace amounts of the larvicide are excreted in milk following high dosages.|Orechromis niloticus fingerlings were exposed to the insect growth inhibitor diflubenzuron for 21 days. Diflubenzuron was introduced to the aquariums where fish were maintained at the beginning of the experiment, then its level in water, gills and liver was detected after 1, 7, 14 and 21 days. The fish accumulated diflubenzuron 76 and 99 times greater than the water content when kept in an ambient concentration of 2.5 and 5 mg/L, respectively, indicating a low bioaccumulation potential. Some degradation products of diflubenzuron were found mainly in liver and water.|There is limited absorption of diflubenzuron across the skin and intestinal lining of mammals, after which enzymatic hydrolysis and excretion rapidly eliminate the pesticide from tissues.|For more Absorption, Distribution and Excretion (Complete) data for DIFLUBENZURON (16 total), please visit the HSDB record page.

The mechanisms of detoxification of the benzoylphenylureas, diflubenzuron, and teflubenzuron in the Egyptian cotton leafworm, Spodoptera littoralis, were examined, as were rates of penetration, degradation, and inhibition of benzoyphenylureas hydrolase(s) both in vivo and in vitro. The results were considered in connection with the toxicity of these compounds. Teflubenzuron was 10 times more toxic than diflubenzuron to fourth instar larvae of spodoptera littoralis. Profenofos and S,S,S-tributylphosphorotrithioate synergized both diflubenzuron and teflubenzuron, indicating that the major route of detoxification in spodoptera littoralis was through hydrolysis. Limited synergism by piperonly butoxide indicated that mixed function oxidase enzymes play a relatively small role in benzoyphenylureas detoxification. ... In Spodoptera littoralis, diflubenzuron was metabolized more rapidly than teflubenzuron: based on the relative amount of parent compound present in the larval body, about 58% of extracted radiocarbon was unchanged teflubenzuron compared to only 38% diflubenzuron. In the excreta, unchanged teflubenzuron was excreted more slowly than the metabolites (42% recovered as parent compound), compared to diflubenzuron in which 79% of the total extract was present as parent compound. Pretreatment of the fourth instar with sublethal doses of profenofos resulted in a significant decrease in metabolism, more so with diflubenzuron than with teflubenzuron. A positive correlation was found between in vivo diflubenzuron metabolism inhibition and toxicity. In in vitro assays, diflubenzuron was hydrolyzed more rapidly than teflubenzuron by all tissue extracts. Profenofos was more effective in inhibiting the hydrolysis in vitro of diflubenzuron compared to teflubenzuron, as indicated by a lower I50 value and steeper slope. /The/ results indicate that reduced penetration and fast elimination of unchanged (14)(C)diflubenzuron together with rapid metabolism, which occurs mainly through hydrolysis, are defense mechanisms which contribute to diflubenzuron detoxification in spodoptera littoralis.|After oral treatment of a cow and a castrated sheep with labeled diflubenzuron, urine was collected and analyzed. TLC indicated the presence of eight labeled materials. The major compounds in the sheep urine were identified as 2,6-difluorobenzoic acid and the hippurate analog. In the cow's urine, 2,6-difluoro-3-hydroxydiflubenzuron was the major metabolite. Metabolites N-((4-chloro-2-hydroxyphenyl)aminocarbonyl)-2,6-difluorobenzamide and N-((4-chloro-3-hydroxyphenyl)aminocarbonyl)-2,6-difluorobenzamide were also seen in urine of both cow and sheep but the 4-chlorophenylurea was seen only in the urine of the cow. Feces of both animals contained ... 2,6-difluoro-3-hydroxydiflubenzuron, N-((4-chloro-2-hydroxyphenyl)aminocarbonyl)-2,6-difluorobenzamide, and N-((4-chloro-3-hydroxyphenyl)aminocarbonyl)-2,6-difluorobenzamide. In the bile, ... 2,6-difluoro-3-hydroxydiflubenzuron, N-((4-chloro-2-hydroxyphenyl)aminocarbonyl)-2,6-difluorobenzamide, and N-((4-chloro-3-hydroxyphenyl)aminocarbonyl)-2,6-diflurorbenzamide also appeared in addition to unidentified conjugates. Incubation of bile water-soluble metabolites with b-glucuronidase-aryl sulfatase converted about half the labeled material into organic extractable materials. Although TLC indicated eight radioactive compounds, none were identified. Analysis of milk indicated the presence of unchanged diflubenzuron, 2,6-difluorobenzamide, 2,6-difluorohippuric acid, and an unidentified compound. Digestive fluids of sheep and cattle did not significantly degrade diflubenzuron. When metabolite V /2,6-difluoro-3-hydroxydiflubenzuron/ was orally administered to rats, almost all of the material was excreted within 3 days. Analyses indicated the presence of five additional compounds. None were identified.|After oral admin to rats of 5 mg diflubenzuron labeled with H3 in the benzoyl and with C14 in the aniline moiety, 95% of the H3 and 70-75% of the C14 radioactivity were retrieved in urine and feces. 2,6-DFBA was shown to constitute more than half of the urinary metabolites. Up to 1% of an oral dose of 5 mg C14-diflubenzuron labeled at the benzoyl moiety was recovered in the expired air of rats.|Diflubenzuron was applied topically to adult stable flies and houseflies. Stable flies metabolized only about 2% of the diflubenzuron while in houseflies this amounted to about 10%. Metabolism in the two flies differed qualitatively as well. Extracts of stable flies contained 2,6-difluorobenzamide and 4-chloroacetanilide. Extracts of houseflies did not contain these. Two unidentified metabolites were seen in house flies but not stable flies. In addition to these, 4-chlorophenylurea and one unknown compound were observed in both flies.|For more Metabolism/Metabolites (Complete) data for DIFLUBENZURON (13 total), please visit the HSDB record page.

... The half life of diflubenzuron appears to be 12 hr in rat and sheep and 18-20 hr in the cow.

Diflubenzuron has a good inhibitory action on several proteases, including chymotrypsin. ... Proteases such as chymotrypsin are known to activate chitin synthetase. Inhibition of naturally occurring protease (B) should therefore lead to a decrease in chitin synthesis activity. This mechanism, coupled with the effect of diflubenzuron on chitin synthesis, could explain the effectiveness of this compound on cuticular deposition.|Diflubenzuron acts by inhibition of chitin synthesis and so interferes with the formation of the insect cuticle. This action is quite specific; related biochemical processes, such as chitin synthesis in fungi, and biosynthesis of hyaluronic acid and other mucopolysaccharides in chickens, mice and rats are not affected. In insect and rust mites, this mode of action can result larvicidal and ovicidal effects at the time of molting of the larvae or at hatching of the eggs.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Inhalation of material may be harmful. Contact may cause burns to skin and eyes. Inhalation of Asbestos dust may have a damaging effect on the lungs. Fire may produce irritating, corrosive and/or toxic gases. Some liquids produce vapors that may cause dizziness or suffocation. Runoff from fire control may cause pollution. (ERG, 2016)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. (ERG, 2016)

Skin decontamination. Wash skin with soap and water ... . Eye contamination should be removed by prolonged flushing of the eye with copious amounts of clean water or saline. If irritation persists, obtain specialized medical treatment. Sensitization reactions may require steroid therapy. /Haloaromatic substituted ureas/|Gastrointestinal decontamination. If large amounts of propargite have been ingested and the patient is seen within an hour, consider gastrointestinal decontamination. For small ingestions, consider oral administration of activated charcoal and sorbitol. /Haloaromatic substituted ureas/|The acute oral toxicity of diflubenzuron for humans is low. There is no specific antidote. Treat symptomatically, when required. If oil-based products have been ingested and the victim starts vomiting, it may be advisable to perform gastric lavage, in order to avoid aspiration into the lungs.|/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/|For more Antidote and Emergency Treatment (Complete) data for DIFLUBENZURON (6 total), please visit the HSDB record page.

/OTHER TOXICITY INFORMATION/ Irritant effects are not reported and systemic toxicity is low.|/OTHER TOXICITY INFORMATION/ The acute oral toxicity of diflubenzuron for humans is low.

Diflubenzuron

Granular, oil dispersible concentrate, suspension concentrate, wettable powder, flowable.|Premix Partners: Methomyl.|Dimilin WP-25, wettable powder (250 g ai/kg); Dimilin G1 and G4 granules (10 or 40 g/kg); Dimilin ODC-45, ultra-low volume liquid, hot fogging concentrate (450 g/l).|F793 Insecticide (Farnam Companies, Inc.): Active ingredient: Diflubenzuron 0.24%.|For more Formulations/Preparations (Complete) data for DIFLUBENZURON (41 total), please visit the HSDB record page.

Benzamide, N-[[(4-chlorophenyl)amino]carbonyl]-2,6-difluoro-: ACTIVE|The WHO Recommended Classification of Pesticides by Hazard identifies diflubenzuron (technical grade) as Class III: slightly hazardous; Main Use: larvicide.

A novel microextraction technique, named in-situ metathesis reaction, combined with ultrasound-assisted ionic liquid dispersive liquid-liquid microextraction was developed for the determination of five phenylurea pesticides (i.e., diuron, diflubenzuron, teflubenzuron, flufenoxuron, and chlorfluazuron) in environmental water samples. In the developed method, 360 uL LiNTf(2) aqueous solution (0.162 g/mL) was added to the sample solution containing a small amount of [C(6)MIM]Cl (0.034 g) to form a water-immiscible ionic liquid, [C(6)MIM]NTf(2), as extraction solution. The mixed solutions were placed in an ultrasonic water bath at 150 W for 4min and centrifuged at 3500 rpm for 10 min to achieve phase separation. After centrifugation, fine droplets of the extractant phase settled to the bottom of the centrifuge tube and were directly injected into the high-performance liquid chromatography system for analysis. The quantity of [C(6)MIM]Cl, the molar ratio of [C(6)MIM]Cl and LiNTf(2), ionic strength, ultrasound time, and centrifugation time, were optimized using a Plackett-Burman design. Significant factors obtained were optimized by employing a central composite design. The optimized technique provides good repeatability (RSD 2.4 to 3.5%), linearity (0.5 ug/L to 500 ug/L), low LODs (0.06 ug/L to 0.08 ug/L) and great enrichment factor (244 to 268). The developed method can be applied in routine analysis for the determining of phenylurea pesticides in environmental samples.|The viability of tandem photochemical reaction-chemiluminescence detection has been studied for the determination of five benzoylurea insecticides, namely, diflubenzuron, triflumuron, hexaflumuron, lufenuron and flufenoxuron. The 'on-line' photochemical reaction of benzoylurea pesticides provides an enhanced chemiluminescence response of the pesticides during their oxidation by potassium hexacyanoferrate(III) and sodium hydroxide, whose signal increases with the percentage of acetonitrile in the reaction medium. The determination was performed using a photoreactor consisting of a PFA (perfluoroalkoxy) tube reactor coil (5 mx1.6-mm O.D. and 0.8-mm I.D.) and an 8-W xenon lamp. As the yield of the photoderivatization process and the chemiluminescent signals depend on the percentage of acetonitrile, the chromatographic column (a Gemini C18, Phenomenex 150 mmx4.6 mm, 5-microm particle size) was chosen with the aim of using high percentages of this organic solvent in the mobile phase. Previous studies showed that the rate of the chemiluminescent reaction was very fast. Therefore, a modification was carried out in the detector in order to mix the analytes and reactants as near as possible to the measure cell. The optimized method was validated with respect to linearity, precision, limits of detection and quantification accuracy. Under the optimised conditions, linear working range extends three orders of magnitude with the relative standard deviation of intra-day precision below 10% and detection limits between 0.012 and 0.18 ug/mL, according to the compound. The proposed method has been successfully applied to the determination of benzoylureas in cucumber with good results.|A high performance liquid chromatographic (HPLC) method was developed to determine the concentration of diflubenzuron, a delousing agent used in fish farming, in marine mud and shell sand. The recovery of diflubenzuron from mud was 100.8+/-1.1% and 105.5+/-4.3% for shell sand. The limit of quantitation was found to be 0.1 ug/g. The stability of diflubenzuron was studied under laboratory conditions in marine sediments at different temperatures (4 and 14 degrees C). No degradation of diflubenzuron occurred in the organic rich mud sediment or in the shell sand sediment during the experimental period of 204 days. Increasing the temperature from 4 to 14 degrees C had no effect on the stability. Furthermore, diflubenzuron showed to be persistent in both mud and shell sand sediment since no detectable diffusion from the sediment to the water phase occurred during the experimental period of 204 days. Increasing the water current in the tanks had no effect on the persistence. Under field conditions, the concentrations of diflubenzuron found in the organic material from sediment traps placed 2 m from the bottom under the cage in a fish farm during medication were high and ranged from 71 to 259 ug/g. The concentrations of diflubenzuron in the sediment under the fish farm were, however, low, with a maximum concentration of 5.4 ug/g. The dispersion of diflubenzuron to the sediment was limited to less than 20 m from the edge of the cage in every direction. Fifteen months following the medication, only traces (< 0.1 ug/g) of diflubenzuron were detected in the sediment under the fish farm. Possible explanations for this decrease are resuspension and redistribution of sediment and/or oxic degradation of the drug.|Residues may be determined by high performance liquid chromatography or gas liquid chromatography after hydrolysis to 4-chloroaniline which is converted to a derivative.|For more Analytic Laboratory Methods (Complete) data for DIFLUBENZURON (7 total), please visit the HSDB record page.

Agrochemicals -> Insecticides|Veterinary Drug -> INSECTICIDE; -> JECFA Functional Classes|Insecticides|Environmental transformation -> Pesticides (parent, predecessor)|INSECTICIDES

Diflubenzuron has known environmental transformation products that include CGA 149776 and CPU 4-chlorophenylurea.

Veterinary Drug -> INSECTICIDE;