Tetrachlorvinphos

Insecticides

Active substance -> EU Pesticides database: Not approved

Pesticides -> Organophosphate Insecticides

Pesticide (Tetrachlorvinphos) -> USDA PDB

Tan to brown crystalline solid

Powder

Off-white crystalline solid

less than 1 mg/mL at 73 °F (NTP, 1992)

SOLUBILITY IS LOW IN HYDROCARBON SOLVENTS; TECHNICAL RABON NOT LESS THAN 94% BY WT ACTIVE INGREDIENT. /TECHNICAL PRODUCT/

Solubility in acetone <200, dichloromethane 400, xylene <150 (all in g/kg, 20 °C)

Partially soluble in chloroform

Limited solubility in most aromatic hydrocarbons.

In water, 11 mg/L at 20 °C

203 to 207 °F (NTP, 1992)

97-98 °C

Melting point = 94-97 °C

4.2e-08 mmHg at 68 °F (NTP, 1992)

0.00000004 [mmHg]

4.20X10-8 mm Hg at 20 °C

Tetrachlorvinphos appears as colorless crystals or white powder. Somewhat corrosive. (NTP, 1992)

Colorless or off-white solid with a mild chemical odor; [HSDB]

STABLE TO LESS THAN 100 °C; SLOWLY HYDROLYZED IN WATER, 50% LOSS OCCURRING @ 50 °C IN 1300 HR @ PH 3, IN 1060 HR @ PH 7, IN 80 HR @ PH 10.5 /TECHNICAL PRODUCT/

Hydrolyzes in an alkaline environment, & is slowly hydrolyzed in acid & neutral environments.

This chemical does not meet GHS hazard criteria for 1.3% (1 of 79) of reports.

Warning

H302 (98.7%): Harmful if swallowed [Warning Acute toxicity, oral]

P203, P261, P264, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P317, P318, P321, P330, P362+P364, P391, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 79 reports by companies from 5 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Warning

Hazard Traits - Carcinogenicity; Environmental tox

Hazard Traits - Developmental Toxicity; Neurotoxicity

Gardona is listed in the dataset of EPA Human Health Benchmarks for Pesticides under the Safe Drinking Water Act (40 eCFR 141)

Tetrachlorvinphos is listed in the dataset of EPA Human Health Benchmarks for Pesticides under the Safe Drinking Water Act (40 eCFR 141)

2002/2076

Tetrachlorvinphos: Does not have an individual approval but may be used under an appropriate group standard

May cause irritation; A cholinesterase inhibitor; Effects in high-dose animal studies include convulsions; [MSDSonline] 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. Causes allergic contact dermatitis (DSEN); TLV Basis = liver, kidney and thyroid effects; [ACGIH TLVs and BEIs]

USEPA/OPPTS; Reregistration Eligibility Decision (RED) Tetrachlorvinphos. EPA 738-R-95-041 159 pp. (September 1995). This document provides a thorough review of the scientific data underlying this pesticide's registration and fulfills the EPA's requirement to determine whether pesticides containing this active ingredient are eligible for reregistration before calling in data on products.

USEPA Office of Pesticide Programs; Tolerance Reassessment Eligibility Decision and Reregistration Eligibility Decision Addenda for Tetrachlorvinphos Case No. 032 184 pp. (2006) describes additional actions taken by EPA on the basis of a review of common mechanisms for organophosphate pesticides.

DHEW/NCI; Bioassay of Tetrachlorvinphos for Possible Carcinogenicity (1978) Technical Rpt Series No. 33 DHEW Pub No. (NIH) 78-833

Tolerances are established for residues of the insecticide tetrachlorvinphos (2-chloro-1-(2,4,5-trichlorophenyl) vinyl dimethyl phosphate) in or on the following food commodities: [Table#4789]

Tetrachlorvinphos may be safely used in accordance with the following prescribed conditions: (i) It is used in the feed of beef, dairy cattle, and horse at a rate of 0.00015 pound (0.07 gram) and swine at the rate of 0.00011 pound (0.05 gram) per 100 pounds of body weight per day. (ii) It is used for control of fecal flies in manure of treated cattle, horse, and swine. (iii) To assure safe use of the pesticide, the label and labeling of the pesticide formulation shall conform to the label and labeling registered by the United States Environmental Protection Agency.

The Agency has completed its assessment of the occupational and residential risks associated with the use of pesticides containing the active ingredient tetrachlorvinphos, as well as a dietary risk assessment that has not yet considered the cumulative effects of organophosphates as a class. Based on a review of these data and public comments on the Agency's assessments for the active ingredient tetrachlorvinphos, EPA has sufficient information on the human health effects of tetrachlorvinphos to make interim decisions as part of the tolerance reassessment process under FFDCA and reregistration under FIFRA, as amended by FQPA. The Agency has determined that tetrachlorvinphos is eligible for tolerance reassessment provided that: (i) current data gaps and additional data needs are addressed; (ii) the risk mitigation measures outlined in this document are adopted, and label amendments are made to reflect these measures; and (iii) cumulative risks considered for the organophosphates support a final reregistration eligibility decision. Label changes are described in Section IV. Appendix B identifies the generic data requirements that the Agency reviewed and lists the submitted studies that the Agency found acceptable. Although the Agency has not yet considered cumulative risks for the organophosphates, the Agency is issuing this interim assessment now in order to identify risk reduction measures that are necessary to support the continued use of tetrachlorvinphos. Based on its current evaluation of tetrachlorvinphos alone, the Agency has determined that tetrachlorvinphos products, unless labeled and used as specified in this document, would present risks inconsistent with FIFRA and/or FQPA. Accordingly, should a registrant fail to implement any of the risk mitigation measures identified in this document, the Agency may take regulatory action to address the risk concerns from use of tetrachlorvinphos.

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. Tetrachlorvinphos 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: 0321; Pesticide type: insecticide; Registration Standard Date: 10/01/88; Case Status: RED Approved 09/95; OPP has made a decision that some/all uses of the pesticide are eligible for reregistration, as reflected in a Reregistration Eligibility Decision (RED) document.; Active ingredient (AI): Tetrachlorvinphos; Data Call-in (DCI) Date(s): 06/24/92; AI Status: OPP has completed a Reregistration Eligibility Decision (RED) document for the case/AI.

A portion of even the most flammable materials is likely to be lost by vaporization. ... The smoke from an open fire used to destroy pesticides will contain some of the poison. Burning should be attempted only in an isolated place. Inhalation of smoke must be avoided. /Pesticides/

Acute Tox. 4 (98.2%)

Acute Tox. 4 (98.7%)

Acute toxicity (Oral) - Category 4

Serious eye damage/eye irritation - Category 2B

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

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]

... Must be stored in its sealed original containers, in well-aired, fresh & dry storehouses or in shaded and possibly well-aired places. It is recommended that the product's temp ... not exceed 25-30 °C, and kept ... away from sources of heat, free flames or spark-generating equipment. Containers must be stacked in such a way as to permit free circulation of air ... at bottom and inside of piles. Storage areas must be located at suitable distance from inhabited buildings, animal shelters, and food stores; moreover, they must be inaccessible to unauthorized persons, children, and domestic animals.

SMALL SPILLS AND LEAKAGE: Should a spill occur while you are handling this chemical, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with 60-70% ethanol and transfer the dampened material to a suitable container. Use absorbent paper dampened with 60-70% ethanol to pick up any remaining material. Seal the absorbent paper, and any of your clothes, which may be contaminated, in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with 60-70% ethanol followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure 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, aquatic, and plant life; and conformance with environmental and public health regulations.

Tetrachlorvinphos stable < 100 °C can be slowly hydrolyzed in water with a 50% loss occurring @ 50 °C in 1300 hr at pH 3, in 1060 hr @ pH 7, in 80 hr @ pH 10.5. Recommendable method: Incineration. Peer review: Incineration @ high temp in a unit with effluent gas scrubbing is recommendable. (Peer-review conclusions of an IRPTC expert consultation (May 1985))

Manufacturers or formulators of very large amounts of pesticides may find it advantageous to build incinerators adequate to destroy all organic pesticides and equipped with scrubbers to remove acid wastes. /Organic pesticides/

Products Intended Primarily for Occupational Use: Application Restrictions: Do not apply this product in a way that will contact workers or other persons, either directly or through drift. Only protected handlers may be in the area during application.

Products Primarily for Occupational Use: Follow manufacturer's instructions for cleaning/maintaining PPE. If no such instructions for washables, use detergent and hot water. Keep and wash PPE separately from other laundry.

Products Primarily for Occupational Use: Users should wash hands before eating, drinking, chewing gum, using tobacco, or using the toilet.

Products Primarily for Occupational Use: Users should remove clothing immediately if pesticide gets inside. Then wash thoroughly and put on clean clothing.

For more Preventive Measures (Complete) data for TETRACHLORVINPHOS (13 total), please visit the HSDB record page.

Tolerances are established for residues of the insecticide tetrachlorvinphos (2-chloro-1-(2,4,5-trichlorophenyl) vinyl dimethyl phosphate) in or on the following food commodities: [Table#4788]

Tetrachlorvinphos may be safely used in accordance with the following prescribed conditions: (i) It is used in the feed of beef, dairy cattle, and horse at a rate of 0.00015 pound (0.07 gram) and swine at the rate of 0.00011 pound (0.05 gram) per 100 pounds of body weight per day. (ii) It is used for control of fecal flies in manure of treated cattle, horse, and swine. (iii) To assure safe use of the pesticide, the label and labeling of the pesticide formulation shall conform to the label and labeling registered by the United States Environmental Protection Agency.

MINIMUM PROTECTIVE CLOTHING: If Tyvek-type disposable protective clothing is not worn during handling of this chemical, wear disposable Tyvek-type sleeves taped to your gloves.

Worker risks are of concern with the maximum level of protection for mixers, loaders, and applicators in poultry egg production operations applying wettable powder formulations with a low-pressure handwand and paint-on application of the EC formulation. ... The following mitigation measures are required: Restrict the use of low pressure handwands for wettable powder (WP) applications to spot treatment in poultry facilities and require double layer clothing, gloves, and dust/mist respirator for mixers, loaders, and applicators engaging in low pressure handwand activities using the WP formulations in egg and broiler facilities. ... Double layer clothing, gloves, and dust/mist respirator for mixers, loaders, and applicators using dusting equipment to apply WP formulation as dusts. Double layer clothing, gloves, and dust/mist respirator for mixers, loaders, and applicators engaging in paint-on activities using WP formulations.

In addition, worker risks exceeded the /EPA's/ level of concern with baseline PPE for handlers engaging in backpack, dusting, groundboom, and low pressure handwand activities. The following mitigation measures are required: ... Double layer clothing and gloves for workers when handling backrubber devices. Single layer and gloves for loaders and others handling dust bags.. Single layer clothing and gloves for mixers, loaders, and applicators engaging in groundboom activities using the EC and WP formulations. Single layer clothing and gloves for mixers, loaders, and applicators engaging in low pressure handwand activities using the EC formulations in poultry facilities. Single layer clothing and gloves for mixers, loaders, and applicators engaging in backpack spraying activities. Single layer clothing and gloves for workers when handling ear tags, mineral blocks, and pellets (oral larvicide feed-through products).

... Tetrachlorvinphos was ... monodealkylated by ... glutathione alkyl transferase. ... in mice ... pretreatment with diethyl maleate & methyl iodide, which reduce liver glutathione levels, potentiated toxicity of organophosphorus insecticides that are demethylated by glutathione transferase.

The effect of tetrachlorvinphos (TCVP) on liver procaine esterase (PROCase) and procaine toxicity was studied in rats. A single oral dose of 500 mg/kg of TCVP caused a remarkable decrease in PROCase (40% of control) 24 hr later and increased the mortality after injection of procaine (250 mg/kg, ip) from 54 to 87%. Conversely, PROCase was elevated to 140% of the control and mortality decreased from 54 to 25% on day 3. With repeated administration of TCVP (500 mg/kg/day) for 5 days, the PROCase activity that was inhibited on day 1 was gradually restored to normal levels by 5 days and the mortality altered to 25%. The inducible effect on PROCase was examined using desmethyl tetrachlorvinphos, a metabolite of TCVP without inhibitory effect on the enzyme; PROCase activity was enhanced to 1.6-fold of the control and procaine concentration in the brain was reduced to 30% of the control, accompanied with no death of rats after procaine injection. Electrophoresis of the solubilized liver microsomal fraction confirmed the inducible effect of TCVP on PROCase; microsomal protein from the TCVP-treated rate was more deeply stained than that from the control, and the PROCase activity of 2 anodic bands increased in the TCVP-treated microsomes. Thus, TCVP has a dual action on PROCase, inducible and inhibitory, and the direct inhibitory effect of TCVP might mask the increased amt of the enzyme induced by repeated administration of TCVP. The dual effect of TCVP on PROCase would cause the change in procaine toxicity.

LD50 Anas platyrhynchos (Mallard duck) oral much greater than 2000 mg/kg /technical product/

LC50 Colinus virginianus (northern bobwhite) diet >5000 ppm for 8 days

LD50 Phasianus colchicus (Pheasant) oral /> or =/ 2000 mg/kg /technical product/

LC50 Cyanocitta cristata (Blue jay, juvenile) diet 995 ppm for 8 days (95% confidence interval: 870-1140 ppm)

For more Ecotoxicity Values (Complete) data for TETRACHLORVINPHOS (18 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 2,000(SRC), determined from a log Kow of 3.53(2) and a regression-derived equation(3), indicates that tetrachlorvinphos is expected to have low mobility in soil(SRC). Volatilization of tetrachlorvinphos from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.8X10-9 atm-cu m/mole(SRC), derived from its vapor pressure, 4.2X10-8 mm Hg(4), and water solubility, 11 mg/L(5). Tetrachlorvinphos is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(4). A biodegradation half-life of <8 days in soil(6) suggest that biodegradation may be an important fate process in soil(SRC).

TERRESTRIAL FATE: The half-life of tetrachlorvinphos in soil has been reported to range from approximately 15-22 days(1). When tetrachlorvinphos granules were applied at 1.5 kg/ha, residues persisted for 60 days(2). Within 7 days of application residues were detected to a depth of 22.5 cm(2). In another study, when tetrachlorvinphos was sprayed on peas, small amounts of the insecticide penetrated to 15 cm depth(3). The transformation rate of tetrachlorvinphos in four soils at 15 °C was determined from the residue remaining after 30 days of incubation in the laboratory in subdued daylight(4). The rates are approximately first order, corresponding to half-lives (soil, half-life): of medium loam (pH 8.0, water content 19% on dry weight), 9 days; clay loam (pH 8.0, water content 20% on dry weight), 6 days; sandy loam (pH 7.9, water content 16% on dry weight), 6 days; peat (pH 6.4, water content 100% on dry weight), 11 days, respectively(4,5). The degradation rate was greater than would be expected on the basis of in vitro hydrolysis studies, and the reaction in soil is probably mostly microbial(6). Taking into account the adsorption and transformation rates, there should be negligible leaching of tetrachlorvinphos from the root zone(5).

TERRESTRIAL FATE: Granules of tetrachlorvinphos were applied to soil (sandy loam illite clay, pH 8.2, organic carbon 0.32%) in bands at 1.5 kg/ha in a field study. The compound was applied in September and rainfall was 7, 12, 0, 4, 32, and 0 mm in Sept, Oct, Nov, Dec, Jan, and Feb, respectively. Residues of tetrachlorvinphos reached beyond the 15 cm depth. Tetrachlovinphos concentrations in the 1-15 cm layer were 5.0, 3.5, 2.5, 1.25, 0.3, and not detected after 0, 7, 15, 30, 45, and 60 days respectively(1). Concentrations in the 15-30 cm layer were 0.55, 0.50, 0.30, and not detected after 7, 15, 30, and 45 days respectively(1). A field half-life of 14 days was calculated(1).

TERRESTRIAL FATE: After application to soil, the initial degradation product is 2,4,5-trichlorophenacyl chloride; after 30 days, the major metabolites are 1-(2',4',5'-trichlorophenyl)ethan-1-ol, 1-(2',4',5'-trichlorophenyl)-2-chloroethan-1-ol, and 2,4,5-trichloroacetophenone(1). The main metabolites in soil are also plant metabolites and therefore plants would not be exposed to residues in the soil that were not also present in the crops as a result of foliar application(2). In laboratory studies there was no evidence of isomerization(2). However, since the pesticide was mixed into the soil, there was no opportunity for photochemical reactions as would be possible under field conditions when tetrachlorvinphos is applied to the soil surface(2).

For more Environmental Fate (Complete) data for TETRACHLORVINPHOS (6 total), please visit the HSDB record page.

In a 1992-1993 FDA statistically-based study, tetrachlorvinphos was not found in domestic (n=710) and imported (n=949) pears or domestic (n=1,219) and imported (n=144) tomatoes at a 0.03 ppm level of quantitation(1). In a 10-year FDA study of ready-to-eat foods (230 food items, 17,050 samples), tetrachlorvinphos was only found in 1 sample of raw peaches at 0.0050 ppm(2). No tetrachlorvinphos (detection limit 2.0 ppm) was found on 6,970 samples of produce surveyed between 1989 and 1991(3). Of 19,851 samples of domestic and imported food and feed surveyed by the FDA Los Angeles District Laboratory between 1981 and 1986, only two contained tetrachlorvinphos, one in the range 0.05-0.1 ppm and the other in the range 0.1-0.5 ppm(4).

Tetrachlorvinphos residues were found in FDA's Total Adult Diet Study (3744 samples) in FY83-86(1). The number of positive samples was not reported, indicating an incidence level of <2%(1). During FDA's regulatory monitoring of domestic and imported adult food eaten by infants and children between FY85 and FY91 (>10,000 surveillance samples), tetrachlorvinphos was only found in 2 of 2,464 samples of domestic apples with a maximum residue 0.26 ppm; a trace was found in 1 of 351 samples of imported apple juice(2). Tetrachlorvinphos was not detected in any of the 27 market baskets of infant and adult foods eaten by infants and children during this time period(2).

/BIRDS and MAMMALS/ Pheasants showed convulsions, tremors and prostration during 2nd and 3rd day following treatment. /Oral; technical product/

/BIRDS and MAMMALS/ The /EPA/ relied on studies using three avian test species. From its review of these data, the Agency concludes that tetrachlorvinphos is practically non-toxic to birds. Mallard duck LD50 >2000 mg/kg; ring-necked pheasant LD50 >2000 mg/kg. and chukar LD50 >2000 mg/kg /From table/. On a subacute dietary basis, tetrachlorvinphos is practically nontoxic to birds. Two studies, one on the mallard duck and one on the bobwhite quail produced LC50s > 5000 ppm.

/AQUATIC SPECIES/ The results of the two 96-hour acute toxicity studies indicate that tetrachlorvinphos is highly toxic to both cold- and warmwater fish. (Test material 94% a.i; Bluegill sunfish 96 hr LC50 of 0.53 ppm and Channel catfish 96 hr LC50 of 0.53 ppm). Formulated product testing on fish has been required because the LC values of the technical pesticide is less than the 50 EEC in the aquatic environment. The results of the 96-hour acute toxicity study with rainbow trout as the test species and with a 75% formulated product (LC50 of 0.43 ppm) indicate that tetrachlorvinphos is highly toxic to freshwater fish

/AQUATIC SPECIES/ The chronic effect of an exposure to a sublethal concentration of commercial formulation of 4 organophosphorus insecticides such as ..., gardona (tetrachlorvinphos) ... on midvitellogenic ovaries of Mystus vittatus was investigated using several histological and histochemical techniques. The loss of stage II and III oocytes accompanied by a significant decline in gonadosomatic index was recorded. The vitellogenesis in treated fishes was ceased as the oocytes did not advance to further stages as evidence by the absence of lipid yolks and the lack of a PAS positive follicular layer. The RNA content of remaining stage I oocytes of exposed fishes resembled that of the stage I oocytes of the control fishes. The absence of delta 5-3 beta-hydroxysteroid dehydrogenase suggested the lack of steroidogenesis. Reduced glucose-6-phosphate dehydrogenase activity was also observed.

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

Tetrachlorvinphos readily degrades on plants under laboratory and field conditions(3). When tetrachlorvinphos was sprayed on peas, 62-94% was found in the upper parts of the plants and 5-24% on the bottom parts of the plants(1). Its initial half-life on apple foliage, cabbage, and rice was 1 day(2). Under conditions in the U.K., the initial half-lives were 2 days on cabbage and 7 days on potato foliage(3). On apple foliage and fruit, the major breakdown products are conjugates of 1-(2,4,5)-trichlorophenyl)ethan-1-ol with sugars, other than beta-D-glucose(2).

No residues of tetrachlorvinphos or 2,4,5-tetrachloroacetophenone, a metabolite, were detected in tissue of a cow given dietary concns of 5 mg/kg of tetrachlorvinphos(1). The USDA reported in 1980 that tetrachlorvinphos was not present in 9 samples of liver and 1 sample of fat from food-producing animals(1). In chickens that were fed tetrachlorvinphos for 52 weeks, tetrachlorvinphos could not be detected (<0.02 ppm) in the eggs and were only infrequently found in the meat (maximum 0.07 ppm)(2).

The following link will take the user to the National Toxicology Program (NTP) Test Agent Search Results page, which tabulates all of the "Standard Toxicology & Carcinogenesis Studies", "Developmental Studies", and "Genetic Toxicity Studies" performed with this chemical. Clicking on the "Testing Status" link will take the user to the status (i.e., in review, in progress, in preparation, on test, completed, etc.) and results of all the studies that the NTP has done on this chemical. /Tetrachlorvinphos (961-11-5)/ [http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=ntpsearch.searchresults&searchterm=961-11-5]

Tolerances are established for residues of the insecticide tetrachlorvinphos (2-chloro-1-(2,4,5-trichlorophenyl) vinyl dimethyl phosphate) in or on the following food commodities: [Table#4789]

Tetrachlorvinphos may be safely used in accordance with the following prescribed conditions: (i) It is used in the feed of beef, dairy cattle, and horse at a rate of 0.00015 pound (0.07 gram) and swine at the rate of 0.00011 pound (0.05 gram) per 100 pounds of body weight per day. (ii) It is used for control of fecal flies in manure of treated cattle, horse, and swine. (iii) To assure safe use of the pesticide, the label and labeling of the pesticide formulation shall conform to the label and labeling registered by the United States Environmental Protection Agency.

The Agency has completed its assessment of the occupational and residential risks associated with the use of pesticides containing the active ingredient tetrachlorvinphos, as well as a dietary risk assessment that has not yet considered the cumulative effects of organophosphates as a class. Based on a review of these data and public comments on the Agency's assessments for the active ingredient tetrachlorvinphos, EPA has sufficient information on the human health effects of tetrachlorvinphos to make interim decisions as part of the tolerance reassessment process under FFDCA and reregistration under FIFRA, as amended by FQPA. The Agency has determined that tetrachlorvinphos is eligible for tolerance reassessment provided that: (i) current data gaps and additional data needs are addressed; (ii) the risk mitigation measures outlined in this document are adopted, and label amendments are made to reflect these measures; and (iii) cumulative risks considered for the organophosphates support a final reregistration eligibility decision. Label changes are described in Section IV. Appendix B identifies the generic data requirements that the Agency reviewed and lists the submitted studies that the Agency found acceptable. Although the Agency has not yet considered cumulative risks for the organophosphates, the Agency is issuing this interim assessment now in order to identify risk reduction measures that are necessary to support the continued use of tetrachlorvinphos. Based on its current evaluation of tetrachlorvinphos alone, the Agency has determined that tetrachlorvinphos products, unless labeled and used as specified in this document, would present risks inconsistent with FIFRA and/or FQPA. Accordingly, should a registrant fail to implement any of the risk mitigation measures identified in this document, the Agency may take regulatory action to address the risk concerns from use of tetrachlorvinphos.

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. Tetrachlorvinphos 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: 0321; Pesticide type: insecticide; Registration Standard Date: 10/01/88; Case Status: RED Approved 09/95; OPP has made a decision that some/all uses of the pesticide are eligible for reregistration, as reflected in a Reregistration Eligibility Decision (RED) document.; Active ingredient (AI): Tetrachlorvinphos; Data Call-in (DCI) Date(s): 06/24/92; AI Status: OPP has completed a Reregistration Eligibility Decision (RED) document for the case/AI.

QP - Antiparasitic products, insecticides and repellents

QP - Antiparasitic products, insecticides and repellents

The cardiovascular actions of anticholinesterase agents are complex, since they reflect both ganglionic and postganglionic effects of accumulated ACh on the heart and blood vessels. The predominant effect on the heart from the peripheral action of accumulated ACh is bradycardia, resulting in a fall in cardiac output. Higher doses usually cause a fall in blood pressure, often as a consequence of effects of anticholinesterase agents on the medullary vasomotor centers of the CNS. /Anticholinesterase agents/

Organophosphorus derivatives act by combining with and inactivating the enzyme acetylcholinesterase. ... The inactivation of cholinesterase by cholinesterase inhibitor pesticides allows the accumulation of large amounts of acetylcholine, with resultant widespread effects that may be ... separated into 4 categories: (1) Potentiation of postganglionic parasympathetic activity. ... (2) Persistent depolarization of skeletal muscle ... (3) Initial stimulation following depression of cells of central nervous system ... (4) Variable ganglionic stimulation or blockade ... /Cholinesterase inhibitor pesticides/

Cholinesterase activity of plasma is significantly higher in men than in women, and this is true no matter which of several choline esters are used as substrate in measuring the enzyme activity. According to some, the difference is confined to young people. There is no sex difference in the red cell enzyme activity. Serum cholinesterase activity of blacks tends to be lower than whites of the same sex. /Organic phosphorus pesticides/

Radiolabelled tetrachlorvinphos was given orally to CD rats as a single low dose (5 mg/kg), as a single high dose (250 mg/kg), and in a series of doses (5 mg/kg). It was almost completely metabolized and most of the label was excreted in urine (46-60%) and feces (38-56%) within 48 hours of dosing. Only minor amounts were found in the tissues. Very little unmetabolized parent compound was recovered. The metabolic processes produced a number of different metabolites which were not all identified. The major metabolite observed in feces was trichlorophenylethanol with females eliminating more of this metabolite (18-34% total administered C) than males (13-23%) at all three dosing levels. Trichlorophenylethandiol was also found in feces ranging from 4-7 % in males and 3-6 % in females. A major metabolite in urine, trichloromandelic acid, was excreted in males at 19-26% but only 10-12% in females. At the high dose, females excreted more (25%) desmethyl tetrachlorvinphos than males (11%). However, there was essentially no difference for the low dose group with males (8%) and females (7%.)

The qualitative nature of the residue in ruminants following oral dosing is adequately understood. In a goat metabolism study the major metabolites identified were free 1-(2,4,5- trichlorophenyl)ethanol, conjugated 1-(2,4,5- trichlorophenyl)ethanol, and 2,4,5-trichloroacetophenone. The proposed metabolic pathway in ruminants following oral administration involves conversion of tetrachlorvinphos to trichlorophenylethanol, which is conjugated to glucuronide or further metabolized to trichloroacetophenone.

Also, the qualitative nature of the residue in ruminants following dermal application is adequately understood. The major residues identified were the parent tetrachlorvinphos, free 1-(2,4,5- trichlorophenyl)-ethanol, conjugated 1-(2,4,5- trichlorophenyl)ethanol, and 2,4,5-trichloroacetophenone.

Tetrachlorvinphos was poorly absorbed through the skin, and most residues adjacent to the application site were not metabolized. Residues that entered the general circulation were extensively metabolized in tissues distal to the application site. In the proposed metabolic pathway in ruminants following dermal application, tetrachlorvinphos was metabolized to either 1-(2,4,5- trichlorophenyl)ethanol, which is conjugated to glucuronic acid, or to 2,4,5-trichloroacetophenone, which is converted to 2,4,5- trichlorobenzoic acid.

For more Metabolism/Metabolites (Complete) data for TETRACHLORVINPHOS (11 total), please visit the HSDB record page.

Drugs that inhibit cholinesterases. The neurotransmitter ACETYLCHOLINE is rapidly hydrolyzed, and thereby inactivated, by cholinesterases. When cholinesterases are inhibited, the action of endogenously released acetylcholine at cholinergic synapses is potentiated. Cholinesterase inhibitors are widely used clinically for their potentiation of cholinergic inputs to the gastrointestinal tract and urinary bladder, the eye, and skeletal muscles; they are also used for their effects on the heart and the central nervous system.

Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics.

A study was conducted with male CD rats using doses of 0.01, 0.1, 1, or 5 mg/sq cm radiolabeled tetrachlorvinphos, with some of each dose group sacrificed at 0.5, 1, 2, 4, or 10 hours. Additionally, there was a group of animals, sacrificed at 72 hours, in which the skin was washed at 10 hours. The area of the dermal application was washed to recover unabsorbed tetrachlorvinphos. Then, the skin, urine, feces, and carcass were analyzed for percent of total tetrachlorvinphos applied. For the group sacrificed at 10 hours, 84% of the total applied (0.1 mg/sq cm ) tetrachlorvinphos was recovered in the wash, and 9.57% remained in the skin, urine, feces, and carcass. This absorption value, 9.57%, is used for assessing human risk following dermal exposure. The percent absorption increased with the duration of exposure and generally decreased with increasing dose. The actual quantity of tetrachlorvinphos absorbed increased with increasing dose.

Laying hens were treated with a wettable powder formulation of stirofos (Rabon, 2-chloro-1-(2,4,5-trichlorophenyl) vinyl dimethylphosphate) by dipping in a 0.5 or 1.0% actual ingredient (AI) water suspension of a 50% wettable powder (WP) stirfos formulation. Stirofos residues were detected in eggs within 1 day after treatment and reached maximum levels 3 days after dipping (0.021 and .035 ppm in the low- and high-dose birds, respectively). After that time, levels of residues in eggs declined rapidly and no sample contained detectable quantities (less than .004 ppm) of stirofos after 21 days...

Single oral dose to rats of (14)C-labelled tetrachlorvinphos ... almost completely eliminated in the urine in 4 days (44-78% during the first 24 hr and 4-15% during the second 24 hr). 78% of the radioactive material was excreted in urine, 16.5% in the feces and 0.5% in the expired air, probably as (14)CO2.

Used against flies in dairies and livestock barns, ectoparasites on poultry, pests of stored products, and other insects that damage forests, crops, and pastures; [HSDB]

Farming (Pesticides) [Category: Industry]

For tetrachlorvinphos (USEPA/OPP Pesticide Code: 083702) ACTIVE products with label matches. /SRP: Registered for use in the U.S. but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./

Organophosphate insecticide. It is currently used as a dermal and feed-through (oral) larvicide in cattle, hogs, goats, and horses; in cattle ear tags to control flies in cattle feedlots; in poultry dust boxes to control poultry mites. It is used to control nuisance and public health pests (flies) in and around refuse sites, recreational areas, and for general outdoor treatment.

... control of ticks and fleas on pets and pet sleeping areas and in collars and shampoos for direct treatment of pets

The additive 2-chloro-1-(2,4,5-trichlorophenyl) vinyl dimethylphosphate may be safely used in accordance with the following prescribed conditions: (a) ... used as a feed additive in feed of beef, dairy cattle, and horses at 0.00015 lb (0.07 g) and swine at 0.00011 lb (0.05 g)/100 lb/ of bw/day; (b) ... used for control of fecal flies on manure of treated cattle, horses, and swine. (c) to assure safe use of the additive, the label and labeling of pesticide formulation containing the feed additive shall conform to the label and labeling registered by the US EPA.

(1975) 4.54X10+7 G (CONSUMPTION)

(1978) 4.54X10+7 G (CONSUMPTION)

Total US usage in 1978 estimated to be 45,000 kg.

Essentially all US usage in 1978 went for controlling insects on livestock and poultry.

Approximately 900,000 lbs active ingredient of tetrachlorvinphos are used annually

REACTION OF 2,2,2',4',5'-PENTACHLOROACETOPHENONE WITH TRIMETHYL PHOSPHITE

Prepn of active Z-isomer: Philips, Ward, Ramsey, US Patents 3,102,842 & 3,553,279 (1963,1971 both to Shell)

Formulation Types Registered: Technical: 98.7% a.i., Manufacturing use: 97.3% a.i., Wettable powder: 50% a.i., Dust: 1%, 3% a.i,. Granular: 0.18% to 7.76% a.i,. one product 97.3% a.i., Pelleted/Tableted 0.3% to 1.25% a.i. primarily mineral blocks for cattle/livestock. Impregnated material: 3%, 13.7% a.i. pet collars, cattle ear tags. Liquid, ready-to-use: 1% to 2% a.i. spray on/wipe on/backrub materials for pets, horses, cattle. Pressurized liquid: 1% a.i. flea and tick spray for cats. Emulsifiable concentrate: 23%, 24% a.i.

TECHNICAL GARDONA CONTAINS 98% CIS-ISOMER. ... TECHNICAL RABON NOT LESS THAN 94% BY WT AI ... WETTABLE POWDER--50% & 75% ACTIVE. EMULSIFIABLE CONCENTRATES--24% ACTIVE INGREDIENT. GRANULES--5% ACTIVE INGREDIENT. EXPTL FORMULATIONS: DUST CONCENTRATE--50% ACTIVE, SPECIAL ULV SUSPENSIONS.

Revap

Technical grade is typically 98% pure.

For more Formulations/Preparations (Complete) data for TETRACHLORVINPHOS (78 total), please visit the HSDB record page.

The WHO Recommended Classification of Pesticides by Hazard identifies Tetrachlorvinphos (technical grade) as unlikely to present an acute hazard in normal use; Main Use: insecticide.

BECAUSE OF RAPID BREAKDOWN, IS NOT EFFECTIVE AGAINST SOIL INSECTS.

... crop uses were voluntarily canceled from product registrations in 1987.