FENCHLORPHOS

Description

Ronnel is a white to light tan crystalline solid.Molecular weight =321.54; Specific gravity (H2O:1) =1.48 at 25℃; Boiling point =(decomposes); Freezing/Melting point= 41℃. Practically insoluble in water;solubility = 0.004% at 25℃.

Chemical properties

Powder or granules. Insoluble in water; soluble in most organic solvents.

Chemical properties

Ronnel is a white to light tan crystalline solid.

The Uses of FENCHLORPHOS

Insecticide.

The Uses of FENCHLORPHOS

Systemic insecticide in livestock

Definition

ChEBI: Fenchlorphos is an organic thiophosphate.

General Description

White to light-tan crystalline solid. Mp: 41° C, Density :1.49 g cm-3 at 25°C. Biocidal (toxic to all animal life in differing degrees) by its action as a cholinesterase inhibitor. Used as an insecticide. Degrades readily in the environment by hydrolysis and oxidation.

Reactivity Profile

FENCHLORPHOS is non-flammable and non-combustible. Decomposes with heating to evolve toxic and corrosive vapors (hydrogen chloride, phosphorus oxides, sulfur oxides). Incompatible with strong oxidizing agents.

Hazard

Toxic by ingestion and inhalation. Cholinesterase inhibitor, use may be restricted. Questionable carcinogen.

Health Hazard

Ronnel is a weak cholinesterase inhibitor and has low toxicity. On both single and repeated doses, ronnel affects the pseudoesterase of the plasma rather than the true acetylcholinesterase of the red blood cells.Ronnel has not been shown to potentiate the effect of other commonly used organophosphorus insecticides.

Safety Profile

Poison by ingestion and intraperitoneal routes. Moderately toxic by skin contact. A cholinesterase inhibitor. An experimental teratogen. Experimental reproductive effects. Human mutation data reported. When heated to decomposition it emits very toxic fumes of Cl-, POx, and SOx. See also PARATHION and CHLOROPHENOLS.

Potential Exposure

Ronnel is both an organochlorine and organophosphorus compound; potential danger to those involved in manufacture, formulation and application of this insecticide for farm (livestock) and household uses. Degrades readily in the environment by hydrolysis and oxidation .

First aid

If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least15 min, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts theskin, remove contaminated clothing and wash immediatelywith soap and water. Speed in removing material from skinis of extreme importance. Shampoo hair promptly if contaminated. Seek medical attention immediately. If thischemical has been inhaled, remove from exposure, beginrescue breathing (using universal precautions, includingresuscitation mask) if breathing has stopped and CPR ifheart action has stopped. Transfer promptly to a medicalfacility. When this chemical has been swallowed, get medical attention. Give large quantities of water and inducevomiting. Do not make an unconscious person vomit.

Environmental Fate

Chemical/Physical. Though no products were identified, the reported hydrolysis halflife at pH 7.4 and 70°C using a 1:4 ethanol/water mixture is 10.2–10.4 hours (Freed et al., 1977). Ronnel decomposed at elevated temperatures on five clay surfaces, each treated with hydrogen, calcium, magnesium, aluminum and iron ions. At temperatures <950°C (125, 300 and 750°C), bentonite clays impregnated with technical ronnel (18.6 wt %) decomposed to 2,4,5-trichlorophenol and a rearrangement product tentatively identified as O-methyl S-methyl-O-(2,4,5-trichlorophenyl) phosphorothioate (Rosenfield and Van Valkenburg, 1965). At 950°C, only the latter product formed. It was postulated that this compound resulted from an acid-catalyzed molecular rearrangement reaction. Ronnel also undergoes base-catalyzed hydrolysis at elevated temperatures. Products include methanol and a new compound that is formed via cleavage of a methyl group from one of the methoxy groups, which is then bonded to the sulfur atom (Rosenfield and Van Valkenburg, 1965).
Ronnel is stable to hydrolysis over the pH range of 5–6 (Mortland and Raman, 1967). However, in the presence of a Cu(II) salt (as cupric chloride) or when present as the exchangeable Cu(II) cation in montmorillonite clays, ronnel is completely hydrolyzed via first-order kinetics in <24 hours at 20°C. The calculated half-life of ronnel at 20°C for this reaction is 6.0 hours. It was suggested that decomposition in the presence of Cu(II) was a result of coordination of the copper atom through the oxygen or sulfur on the phosphorus atom resulting in the cleavage of the side chain containing the phosphorus atom forming O,O-ethyl-O-phosphorothioate and 1,2,4-trichlorobenzene (Mortland and Raman, 1967).
Emits very toxic fumes of chlorides, sulfur and phosphorus oxides when heated to decomposition (Lewis, 1990).

storage

Color Code—Blue: Health Hazard/Poison: Storein a secure poison location. Prior to working with thischemical you should be trained on its proper handling andstorage. Store in tightly closed containers in a cool, wellventilated area away from strong oxidizers. Where possible,automatically transfer material from drums or other storagecontainers to process containers. Sources of ignition, suchas smoking and open flames, are prohibited where thischemical is handled, used, or stored. Metal containersinvolving the transfer of this chemical should be groundedand bonded. Wherever this chemical is used, handled, manufactured, or stored, use explosion-proof electrical equipment and fittings.

Shipping

UN2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. UN2783 Organophosphorus pesticides, solid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.

Incompatibilities

Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explo- sions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, and epoxides. Store at temperatures ＜25-30℃. Organothiophosphates are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrideds and active metals. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides

Waste Disposal

Incineration with added flam- mable solvent in furnace equipped with afterburner and alkali scrubber . In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesti- cide containers. Must be disposed properly by following package label directions or by contacting your local or fed- eral environmental control agency, or by contacting your regional EPA office.