렙토포스

1.53 at 77 °F (EPA, 1998) - Denser than water; will sink

1.53 @ 25 °C

1.53 @25 °C

WHITE CRYSTALLINE SOLID

COLORLESS AMORPHOUS SOLID

Tan waxy solid

SOL IN XYLENE

@ 25 °C: 2.4 MG/L IN WATER, 470 G/L IN ACETONE, 1.3 KG/L IN BENZENE, 142 G/L IN CYCLOHEXANE, 59 G/L IN HEPTANE, 24 G/L IN PROPAN-2-OL

Water solubility= 0.0047 mg/l at 20 °C

158 to 159 °F (EPA, 1998)

70.2-70.6 °C

71 - 72 °C

0.00000002 [mmHg]

Vapor pressure= 2.3X10-8 mm Hg at 20 °C

0.000002 [mm Hg] @25 °C

Leptophos appears as white crystalline or colorless amorphous solid, the technical product is a light tan powder. Used as an insecticide; its use is not permitted in the U.S. (EPA, 1998)

Tan solid; [Merck Index] Colorless or white solid; Technical material is light-brown solid; [CAMEO]

Solid

Danger

H301: Toxic if swallowed [Danger Acute toxicity, oral]

P260, P264, P270, P273, P280, P301+P316, P302+P352, P308+P316, P317, P321, P330, P362+P364, P391, P405, and P501 (click each P-code to see the statement)

Danger

H301 (90.8%): Toxic if swallowed [Danger Acute toxicity, oral]

P260, P264, P270, P273, P280, P301+P316, P302+P352, P308+P316, P317, P321, P330, P362+P364, P391, P405, and P501 (click each P-code to see the statement)

A small number of the organophosphates (OPs) can Induce Delayed Neuropathy (OPIDN). OPIDN usually occurs after ingestion and is usually nonoccupational. [Levy, p. 431] A highly toxic cholinesterase inhibitor that may cause permanent injury or death as a result of normal use; [CAMEO] A weak cholinesterase inhibitor, but is metabolized to the oxygen analog that is relatively potent; Not teratogenic in rabbits dosed orally during pregnancy; May cause delayed neurotoxicity in occupational exposures (delayed neurotoxicity observed in hens); [EPA OHM/TADS] May cause irritation and organ damage; Highly toxic by ingestion; Toxic by skin absorption; [Aldrich MSDS] The average of two baseline respective cholinesterase activity determinations three days apart, with no exposures to enzyme inhibiting pesticides for at least 30 days, is recommended for each worker prior to exposure to cholinesterase inhibitors because of large inter-individual differences in published baseline values. To be established at least once a year. Removal from workplace exposures is recommended until the cholinesterase activity returns to within 20% of baseline. [TLVs and BEIs]

BARLOW JN; TOXICOLOGY AND SAFETY EVALUATION OF PHOSVEL TO EGYPTIAN WATER BUFFALO. WATSON DL & AWA BROWN EDS, PESTICIDE MGMNT & INSECTICIDE RESISTANCE, XVTH INTERNATIONAL CONGRESS OF ENTOMOLOGY, SECTION ON PESTICIDE DEVELOPMENT, MGMNT & REGULATION, WASHINGTON, DC, AUG 20-27, (1976). TOXICOLOGY & SAFETY EVALUATION OF PHOSVEL TO EGYPTIAN WATER BUFFALO ARE REVIEWED.

WATERS EM, GERSTNER HB; LEPTOPHOS: AN OVERVIEW. LITERATURE COMPILATION, 1969-1979; REPORT ORNL/TIRC-78/4 (1979) 94. THE PHYSICAL & CHEMICAL PROPERTIES OF LEPTOPHOS, USE & MODE OF ACTION IN TARGET SPECIES, & METABOLISM & TOXICOLOGY IN THE VERTEBRATES ARE DISCUSSED.

CLEGG DJ; ANIMAL REPRODUCTION AND CARCINOGENICITY STUDIES IN RELATION TO HUMAN SAFETY EVALUATION; DEV TOXICOL ENVIRON SCI 4: 45 (1979). ANIMAL REPRODUCTION & CARCINOGENICITY STUDIES ARE REVIEWED WITH RESPECT TO THEIR USE IN EVALUATING THE SAFETY OF TOXIC CHEMICALS IN HUMANS.

Cherniack MG; Toxicological Screening for Organophosphorus-Induced Delayed Neurotoxicity: Complications in Toxicity Testing; Neurotoxicology 9 (2): 249-71 (1988). Organophosphorus induced delayed neurotoxicity was reviewed and discussed in relation to toxicological screening. Human cases of organophosphorus induced delayed neurotoxicity resulting from exposure to medicinal agents, leptophos, fenthion, and isophenphos were reviewed.

Organophosphates, such as LEPTOPHOS, are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Leptophos is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 500/10,000 lbs.

Acute Tox. 3 (90.8%)

Specific target organ toxicity (single exposure) - category 1

Acute toxicity (Oral) - Category 2

Acute Tox. 3 *

(Non-Specific -- Organophosphorus Pesticide, n.o.s.) Stay upwind; keep out of low areas. Move container from fire area if you can do it without risk. Fight fire from maximum distance. Dike fire control water for later disposal; do not scatter the material.

Biological Exposure Indices (BEI) [ACGIH] - Acetylcholinesterase activity in red blood cells = 70% of individual's baseline; Butylcholinesterase activity in serum or plasma = 60% of individual's baseline; Sample at end of shift; [TLVs and BEIs]

Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. /Parathion/

Self contained breathing apparatus with a full facepiece operated in pressure demand, or other positive pressure mode /should be used in firefighting/. /Parathion/

If material /is/ on fire or /is/ involved in fire, extinguish fire using agent suitable for type of surrounding fire. ... Use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use foam, dry chemical, or carbon dioxide. /Parathion and compressed gas mixture/

If material /is/ on fire or involved in fire, extinguish fire using agent suitable for type of surrounding fire. ... Use water in flooding quantities as fog. Use "alcohol" foam, dry chemical or carbon dioxide. /Parathion mixture, dry/

If material /is/ on fire or involved in fire, do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Solid streams of water may be ineffective. Use "alcohol" foam, dry chemical or carbon dioxide. /Parathion mixture, liquid/

1. VENTILATE AREA OF SPILL OR LEAK. 2. COLLECT FOR RECLAMATION, OR ABSORB IN VERMICULITE, DRY SAND, EARTH, OR A SIMILAR MATERIAL. /PARATHION/

If material is not on fire & is not involved in fire ... build dikes to contain flow as necessary. Attempt to stop leak if ... /it can be done/ without hazard. ... If material leaking (not on fire) consider evacuation from downwind area based on amount of material spilled, location & weather conditions. /Parathion/

Land spill: Dig a pit, pond, lagoon, or holding area to contain liquid, or solidmaterial. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash or cement powder. /Parathion/

Air spill: Apply water spray to knock down vapors. /Parathion/

For more Cleanup Methods (Complete) data for LEPTOPHOS (11 total), please visit the HSDB record page.

Potential candidate for rotary kiln incineration, with a temperature range of 820 to 1,600 °C and a residence time of seconds. Also, a potential candidate for fluidized bed incineration, with a temperature range of 450 to 980 °C, and a residence time of seconds. Also, a potential candidate for liquid injection incineration with a temperature range of 650 to 1,600 °C, and a residence time of 0.1 to 2 seconds. /Parathion/

The following wastewater treatment technologies have been investigated for parathion: Reverse osmosis. /Parathion/

0.057 [mg/m3]

0.63 [mg/m3]

3.8 [mg/m3]

For emergency situations, wear a positive pressure, pressure-demand, full facepiece self-contained breathing apparatus (SCBA) or pressure- demand supplied air respirator with escape SCBA and a fully-encapsulating, chemical resistant suit. (EPA, 1998)

NEOPRENE COATED GLOVES; RUBBER WORKSHOES OR OVERSHOES; LATEX RUBBER APRON; GOGGLES; RESPIRATOR OR MASK APPROVED FOR TOXIC DUSTS & ORGANIC VAPORS. /PARATHION/

Employees should be provided with and required to use impervious clothing, gloves, face shields (eight inch minimum), and other appropriate protective clothing necessary to prevent repeated, or prolonged skin contact with parathion. /Parathion/

Respirator selection, upper limit devices recommended by NIOSH. For concn up to 0.5 mg/cu m use any chemical cartridge respirator with organic vapor cartridge(s) in combination with a dust, mist, and fume filter; or any supplied air respirator; or any self contained breathing apparatus. For concn up to 1.25 mg/cu m use any supplied air respirator operated in a continuous flow mode; or any powered air purifying respirator with organic vapor cartridge(s) in combination with a dust, mist and fume filter. For concn up 2.5 mg/cu m use any chemical cartridge respirator with a full facepiece and organic vapor cartridge(s) in combination with a high efficiency particulate filter; or any supplied air respirator with a full facepiece; or any self contained breathing apparatus with a full facepiece; or powered air purifying respirator with a high efficiency filter with an organic vapor cartridge; or any supplied air respirator with a tight fitting facepiece operated in a continuous flow mode. For concn up to 20 mg/cu m use any supplied-air respirator with a half-mask and operated in a pressure demand or other positive pressure mode. For emergency or planned entry in unknown concentration or IDLH conditions use any self contained breathing apparatus with a full facepiece and operated in a pressure demand or other positive pressure mode; or any supplied air respirator with a full face piece and operated in pressure demand or other positive pressure mode in combination with an auxiliary self contained breathing apparatus operated in pressure demand or other positive pressure mode. Escape: Any air purifying full facepiece respirator (gas mask) with a chin style or front or back mounted canister providing protection against the compound of concern; or any appropriate escape type self contained breathing apparatus. /Parathion/

Wear positive pressure self-contained breathing apparatus. ... Wear appropriate chemical protective clothing. /Parathion and compressed gas mixture; parathion dry mixture; parathion liquid mixture/

LC50 Procambarus >7000 ug/l/96 hr @ 12 °C, early 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. /Technical material 87.2%/

LC50 Salmo clarki (Cutthroat trout) 5.3 ug/l/96 hr @ 10 °C, static bioassay without aeration, pH 7.2-7.5, water hardness 40-50 mg/l as calcium carbonate andalkalinity of 30-35 mg/l. (95% Confidence Limit 4.2-6.8 ug/l), wt 0.6 g /Technical Material 87.2%/

LC50 Salmo gairdneri (Rainbow trout) 20 ug/l/96 hr @ 12 °C, 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. (95% Confidence Limit 12-32 ug/l), wt 1.0 g /Technical material 87.2%/

LC50 Salvelinus namaycush (Lake Trout) 30 ug/l/96 hr @ 12 °C, 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. (95% Confidence limit 21-43 ug/l), wt 2.2 g /Technical material 87.2%/

For more Ecotoxicity Values (Complete) data for LEPTOPHOS (15 total), please visit the HSDB record page.

LEPTOPHOS HAD SHORT-LIVED EFFECTS ON PROCESSES & NUMBERS OF SOIL MICROORGANISMS.

TERRESTRIAL FATE: Laboratory studies have shown that leptophos is adsorbed strongly by soil and will not leach(1); log Koc values of 3.97-5.07 have been experimentally determined(1-2). Aqueous hydrolysis studies have shown that leptophos degrades more rapidly with increases in pH(3); aqueous hydrolysis half-lives of 35, 5.5 and 2.3 weeks have been measured at respective pHs of 6, 7 and 8 at 25 °C(3); therefore, hydrolysis may be an important transformation process in moist, alkaline soils(SRC). Insufficient data are available to assess the relative importance of biodegradation in soil. A foliar half-life of 4.0 days has been reported for endive plants(4). In field studies conducted in Israel, foliar residue levels of leptophos (as applied to tomato and grape plants) had dropped by 40-75%, from initial levels, after three weeks(5); the phenol derivative was a major degradation product(5). Based upon the results a laboratory study and a review of other leptophos persistence studies, it was concluded that leptophos is one of the most persistent organophosphorus compounds in the environment(6).

AQUATIC FATE: The results of various screening studies indicate that chemical degradation of leptophos may be more important in water than biodegradation(1-3). Hydrolysis studies have shown that degradation rates increase with increasing pH(3); at 25 °C, aqueous hydrolysis half-lives of 35, 5.5 and 2.3 weeks have been measured at respective pHs of 6, 7 and 8(3). Direct photolysis tests of methanol solutions of leptophos exposed to sunlight (half-life of about 50 days)(4) have shown that direct photolysis may contribute to transformation in water(SRC). In water, leptophos will partition from the water column to sediment and suspended material(1) and can be expected to remain largely in the sediment. Laboratory studies with various Egyptian natural waters have suggested the degradation rate may decrease in the presence of solids and sediment(5). A measured BCF of 6058 in topmouth gudgeon fish(6) indicates that bioconcentration in aquatic organisms may be an important environmental process(SRC).

ATMOSPHERIC FATE: Based upon a measured vapor pressure of 2.3X10-8 mm Hg at 20 °C(1), leptophos can exist in both the vapor and particulate phases in the ambient atmosphere, although the particulate phase may dominate(2,SRC). It will degrade rapidly in the vapor phase by reaction with photochemically produced hydroxyl radicals with an estimated half-life of about 5 hr(3,SRC). Particulate phase leptophos and aerosols released to air during spray applications of leptophos insecticide can be removed from air physically by dry and wet deposition(SRC).

As part of the US Food and Drug Administration's Total Diet Study (Market Basket Survey of ready-to-eat foods) for fiscal year 1977, leptophos was detected in one of 300 food composites comprised of foods collected from 20 cities nationwide(1); the leptophos was detected in a fruit sample at concn of 0.012 ppm(1). As part of the US Food and Drug Administration's Total Diet Study (Market Basket Survey of ready-to-eat foods) for fiscal year 1976, leptophos was detected in two of 240 food composites comprised of foods collected from 20 cities nationwide(2); the leptophos was detected in garden fruit samples at concns of a trace (concn not available) and 0.009 ppm(2). For fiscal year 1975, leptophos was found in one of 240 food composites (garden fruit class) at a concn of 0.04 ppm(3). For fiscal year 1974, leptophos was found in five of 360 food composites (all in the garden fruit class) at concns of 0.013 to 0.09 ppm(4).

Based upon monitoring results from the US Food and Drug Administration's Total Diet Study (Market Basket Survey) for fiscal years 1976 and 1977, the average daily intake of leptophos from food for the adult male has been estimated to be 0.0005 and 0.0015 ug/kg body weight/day(1).

The adsorption behavior of leptophos in soil and aqueous suspension of soil and sediment was studied in the laboratory(1); based upon results of leaching tests, leptophos was assigned a mobility factor of zero, which indicated that it was not leachable from either sand or various organic soils(1); Freundlich adsorption isotherms measured in a river sediment, sandy loam soil and sand(1) can be used to determine respective log Koc values of 5.07, 4.98 and 4.85(1). An experimentally determined log Koc of 3.97 has also been reported(2). According to a suggested classification scheme(3), these estimated Koc values indicate that leptophos is immobile in soil(SRC).

LEPTOPHOS HAS BEEN IMPLICATED IN POISONING & PARALYSIS OF SOME WORKERS IN TEXAS FACTORY WHERE IT WAS MANUFACTURED.

LEPTOPHOS PRODUCES TOXIC DISTAL AXONOPATHY INVOLVING AXONAL DEGENERATION IN CENTRAL & PERIPHERAL NERVOUS SYSTEM.

... IN ONE STUDY OF EGYPTIAN FARMERS EXPOSED TO LEPTOPHOS BY BOTH RESPIRATORY & DERMAL ROUTES IN CONNECTION WITH APPLICATION OF THE INSECTICIDE TO COTTON, NO MENTION WAS MADE OF POLYNEUROPATHY. CHARACTERISTIC ILLNESS PROPORTIONAL TO INHIBITION OF RED CELL CHOLINESTERASE ACTIVITY WAS OBSERVED.

SYMPTOMATOLOGY: 1. NAUSEA ... VOMITING, ABDOMINAL CRAMPS, DIARRHEA, EXCESSIVE SALIVATION ... 2. HEADACHE, GIDDINESS, VERTIGO & WEAKNESS. 3. RHINORRHEA & SENSATION OF TIGHTNESS IN CHEST ARE COMMON IN INHALATION EXPOSURE. 4. BLURRING OR DIMNESS OF VISION, MIOSIS ... TEARING, CILIARY MUSCLE SPASM, LOSS OF ACCOMMODATION & OCULAR PAIN ... MYDRIASIS ... SOMETIMES SEEN ... PROBABLY DUE TOSYMPATHO-ADRENAL DISCHARGE. 5. BRADYCARDIA OR TACHYCARDIA. VARYING DEGREES OF AV HEART BLOCK ... AS WELL AS ARIAL ARRHYTHMIAS. 6. LOSS OF MUSCLE COORDINATION,SLURRING OF SPEECH, FASCICULATIONS & TWITCHING OF MUSCLES (PARTICULARLY OF TONGUE & EYELIDS), & GENERALIZED PROFOUND WEAKNESS. 7. MENTAL CONFUSION, DISORIENTATION & DROWSINESS. /PARATHION/

SYMPTOMATOLOGY: 8. DIFFICULTY IN BREATHING, EXCESSIVE SECRETION OF SALIVA & OF RESP TRACT MUCUS, ORONASAL FROTHING, CYANOSIS, PULMONARY RALES & RHONCHI & HYPERTENSION, (PRESUMABLY DUE TO ASPHYXIA). 9. RANDOM JERKY MOVEMENTS, INCONTINENCE, CONVULSIONS, & COMA. 10. DEATH PRIMARILY DUE TO RESP ARREST ARISING FROM FAILURE OF RESP CENTER, PARALYSIS OF RESP MUSCLES, INTENSE BRONCHOCONSTRICTION OR ALL THREE. /PARATHION/

In die-away tests using a natural water (pH 7 collected from a drainage ditch in a vegetable growing area of Canada), sterilized natural water, and distilled water, leptophos degraded only slightly more rapidly in the unsterilized natural water over a 16-week incubation period(1); over the 16-week period, approximately 55-60% of the initial leptophos was degraded with removal only several percent more rapid in the unsterilized natural water as compared to the other waters(1); although some biodegradation was occurring, it was concluded that chemical degradation is more important than microbial degradation(1).

Residues of leptophos and its metabolites exhibited bioaccumulation factors of 1443 and 48398 in fish and snail, respectively.

Using a continuous-flow system and a 14-day exposure period a leptophos BCF of 6058 was measured in topmouth gudgeon (Pseudorasbora parva) fish(1-2). This BCF suggests that bioconcentration in aquatic organisms has environmental importance(SRC). A BCF of 773 was estimated from equilibrium concentrations in a bioaccumulation study with bluegill fish(3).

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Leptophos is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 500/10,000 lbs.

... 42 DAYS AFTER APPLICATION OF 2,240 G AI/HA TO CYNODON DACTYLON (BERMUDA GRASS) ... /ITS/ METABOLITE 4-BROMO-2,5-DICHLOROPHENOL 1.30 PPM, /WAS/ ... RECOVERED.

THE BIOTRANSFORMATION IN MICE OF LEPTOPHOS IS RAPID (ONLY SMALL AMOUNTS OF THE PARENT COMPOUND ARE FOUND IN FECES & IN URINE) & PREDICTABLE METABOLITES ARE IDENTIFIED ... 4-BROMO-2,5-DICHLOROPHENOL, MOSTLY CONJUGATED, ACCOUNTED FOR 96% OF A 25 MG/KG DOSE OF [PHENOXY-(14)C]LEPTOPHOS, & TENTATIVE IDENTIFICATION OF THE OXON OF O-DEMETHYL-LEPTOPHOS (1.1%) WAS MADE. COMPLEMENTARY STUDIES WITH [PHENYL-(14)C]LEPTOPHOS REVEALED THAT THE OXON OF O-DEMETHYL-LEPTOPHOS WAS AGAIN ONLY A MINOR URINARY METABOLITE, & THAT METHYL PHENYLPHOSPHONOTHIOIC ACID (56.6%), METHYL PHENYLPHOSPHONIC ACID (17.9%), & PHENYLPHOSPHONIC ACID (15.5%) ACCOUNTED FOR 90% OF THE URINARY LABEL. THE EXTENT OF THE IMPORTANCE OF O-DEMETHYLATION PATHWAYS IN THE BIOTRANSFORMATION OF LEPTOPHOS IS REVEALED BY THE EXCRETION (15.5%) OF PHENYLPHOSPHONIC ACID. THE ABSENCE OF O-DEMETHYL-LEPTOPHOS & PHENYLPHOSPHONOTHIOIC ACID FROM THE URINE MEANS THAT GLUTATHIONE-MEDIATED O-DEMETHYLATION OF LEPTOPHOS IS RELATIVELY UNIMPORTANT, COMPARED WITH THE PRODUCTION OF 4-BROMO-2,5-DICHLOROPHENOL.

LEPTOPHOS OXON WAS MODERATELY HYDROLYZED BY SUSCEPTIBLE SPECIES (LIVER MICROSOMAL FRACTIONS FROM CATS & HENS) & GREATLY HYDROLYZED BY NONSUSCEPTIBLE SPECIES (LIVER MICROSOMAL FRACTIONS FROM RATS & HAMSTERS). RATE OF DETOXIFICATION OF LEPTOPHOS IS INVERSELY CORRELATED WITH IN VIVO SUSCEPTIBILITY OF TESTED SPECIES TO DELAYED NEUROTOXICITY.

WHEN LEPTOPHOS WAS DOSED ENDOTRACHEALLY TO THE RAT, IT WAS METABOLIZED AT A RATE SIMILIAR TO THAT OF AN ORAL DOSE. THE METABOLITES IN THE RAT ARE THE SAME AS THOSE IN THE MOUSE, ALTHOUGH THE PROPORTION OF THE SINGLE METABOLITE THAT HAD RETAINED THE P=S LINKAGE WAS MUCH LESS. THIS IS NOT EXPECTED, AS THE RAT USUALLY MORE EXTENSIVELY OXIDIZES THE P=S GROUP THAN DOES THE MOUSE. RATS DOSED ON THREE CONSECUTIVE DAYS WITH 9.1 & 0.91 MG/KG LEPTOPHOS EXCRETED 30% & 73% RESPECTIVELY OF THE DOSE AS A MIXTURE OF THE THREE KNOWN PHOSPHORUS ACIDS, ACCOMPANIED BY THE SAME YIELD (12 + OR - 1%) OF 4-BROMO-2,5-DICHLOROPHENOL AT EACH DOSAGE.

For more Metabolism/Metabolites (Complete) data for LEPTOPHOS (13 total), please visit the HSDB record page.

AFTER 50 OR 250 MG/KG DOSE, PHOSVEL CONCN IN PLASMA REACHED MAX IN 3 HR, THEN DECLINED RAPIDLY; AFTER 72 HR NO RESIDUES WERE DETECTABLE. ELIMINATION FROM FAT WAS VERY SLOW.

IN SPITE OF SOME TENDENCY TO STORAGE, LEPTOPHOS, IN THE FORM OF WATER-SOLUBLE METABOLITES, IS EXCRETED RAPIDLY BY RODENTS, WITH VIRTUALLY COMPLETE ELIMINATION IN 48 TO 72 HR. IN MICE FED (14)C LEPTOPHOS AT A RATE OF 25 MG/KG THE RATE OF EXCRETION OF THE PHENOXY MOIETY WAS DISTINCTLY FASTER THAN THAT OF THE PHENYL MOIETY; RADIOACTIVITY WAS FOUND IN THE URINE AS LONG AS 6 DAYS AFTER TREATMENT.

IN RATS, EXCRETION OF RADIOACTIVE CARBON WAS ESSENTIALLY COMPLETE IN 72 HR FOLLOWING A SINGLE DOSE OR THE LAST OF A SERIES OF DOSES OF (14)C LEPTOPHOS. SIX DAYS AFTER THE LAST DOSE, THE HIGHEST CONCN OF (14)C WAS IN THE LIVER, BUT IT CONSTITUTED LESS THAN 0.25% OF THE TOTAL DOSE. MORE THAN 97% OF THE RADIOACTIVITY IN THE URINE OF RATS THAT HAD RECEIVED (14)C LEPTOPHOS WAS ORGANOSOLUBLE.

... FOLLOWING A SINGLE DOSE OF (14)C PHENYL LEPTOPHOS APPLIED TO THE COMBS OF HENS AT A SUBNEUROTOXIC RATE OF 50 MG/KG ... A TOTAL OF 35.4% OF THE APPLIED DOSE WAS ABSORBED DURING A 20-DAY EXPERIMENT. RADIOACTIVITY REACHED A PEAK OF 17.1% OF THE DOSE IN 12 HR AFTER APPLICATION; 5% OF THE DOSE STILL REMAINED AFTER 20 DAYS. THE HIGHEST (14)C CONCN AFTER 20 DAYS WERE IN MUSCLE, BRAIN, SPINAL CORD, CONTENTS OF THE LARGE INTESTINE, & BILE, IN THAT ORDER. COMBINED URINARY-FECAL EXCRETION ACCOUNTED FOR 24.3% OF THE APPLIED DOSE; EXPIRED CARBON DIOXIDE ACCOUNTED FOR 1.3% & EGG ACCOUNTED FOR 4.5%.

Used as an insecticide; [Merck Index] For export use only; Used as an insecticide for rice, cotton, fruit, and vegetables; [EPA OHM/TADS]

Banned in the USA in 1975 due to delayed neurotoxic effects; [HSDB]

Farming (Pesticides) [Category: Industry]

NOT PERMITTED FOR USE IN THE USA; EXPERIMENTAL REGISTRATION & TEMPORARY TOLERANCE IN THE US WAS CANCELLED IN LATE 1975 DUE TO DELAYED NEUROTOXIC EFFECTS (1976)

(1972) PROBABLY GREATER THAN 4.54X10+5 G

(1975) PROBABLY GREATER THAN 4.54X10+5 G

REACTION OF O-METHYL PHENYLTHIOPHOSPHONYL CHLORIDE WITH 4-BROMO-2,5-DICHLOROPHENOL.

PRODUCED BY THE REACTION OF PHENYLPHOSPHONOTHIOIC DICHLORIDE WITH METHANOL & TRIMETHYLAMINE IN TOLUENE AT ROOM TEMPERATURE, FOLLOWED BY REACTION WITH POTASSIUM 4-BROMO-2,5-DICHLOROPHENOXIDE IN BOILING TOLUENE ... .

... EMULSIFIABLE CONCN (360 G AI/L); WETTABLE POWDER (450 G/KG); DUST (30 G/KG); GRANULES (50 G/KG). /FORMER/

TECHNICAL MATERIAL, 87.2%; EMULSIFIABLE CONCN, 2.7%.

THE EMULSIFIABLE CONCN IS PARTICULARLY EFFECTIVE AGAINST LEPIDOPTERA, FOR EXAMPLE SPODOPTERA LITTORALIS ON COTTON AT 1.5 KG/HA; ON VEGETABLES & FRUIT AT 100 G/100 L. GRANULES AT 1.5 KG AI/HA ARE EFFECTIVE FOR THE CONTROL OF OSTRINIA NUBILALIS ON MAIZE. THERE IS EVIDENCE THAT IT HAS A POSITIVE TEMPERATURE COEFFICIENT AGAINST LEPIDOPTERA & MAY THEREFORE BE MORE USEFUL IN WARMER CLIMATES. /FORMER/