93-76-5

Light tan solid (melting point 153°C). Insoluble in water. Contact may irritate the skin.

2,4,5-TRICHLOROPHENOXYACETIC ACID(93-76-5) is a weak acid. Reacts with organic and inorganic bases to form water-soluble salts and with alcohols to form esters. Incompatible with strong oxidizing agents and strong bases. Can corrode metals, especially if moist. May harm painted surfaces .

Insoluble in water.

Overexposure to dust by inhalation or ingestion may cause fatigue, nausea, vomiting, lowered blood pressure, convulsions, coma. Dust may irritate eyes and skin.

Those engaged in the manufacture, formulation, and application of this herbicide used to control woody and herbaceous weeds. The EPA has issued a rebuttable presumption against registration of 2,4,5-T for pesticide uses, however. The Viet Nam war era defoliant, Agent Orange, was a mixture of 2,4,5-T and 2,4-D.

Special Hazards of Combustion Products: Toxic hydrogen chloride and phosgene gases may be formed.

Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; give artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. 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. For minor skin contact, avoid spreading material on unaffected skin. Keep victim warm and quiet. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Medical observation is recommended for 24-48 hours after breathing overexposure, as pulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a drug or other inhalation therapy.

UN2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. UN3345 Phenoxyacetic acid derivative pesticide, solid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.

The aqueous solution is a weak acid. Incompatible with sulfuric acid, bases, ammonia, aliphatic amines; alkanolamines, isocyanates, alkylene oxides; epichlorohydrin; strong oxidizers, such as chlorine, bromine, fluorine, and strong bases.

2,4,5-T Acid is an odorless, colorless to tan crystalline solid.

white to light tan odourless solid

Two disposal procedures have been discussed for 2,4,5-T: (1) Mix with excesssodium carbonate, add water and let stand for 24 hours before flushing down the drain with excess water; and (2) pour onto vermiculite and incinerate with wood, paper, and waste alcohol. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. Must be disposed properly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal.

Colorless to pale brown, odorless crystals. Odor threshold from water is 2.92 mg/kg (quoted, Keith and Walters, 1992). Metallic taste.

2,4,5-T was formerly used as a herbicide. Itis currently not used, following a ban by theEPA.

It is suitable for plant cell culture tested. Post-emergence herbicide.

Plant hormone; defoliant; herbicide used to control undesirable brush and woody plants.

ChEBI: A chlorophenoxyacetic acid that is phenoxyacetic acid in which the ring hydrogens at postions 2, 4 and 5 are substituted by chlorines.

2,4,5-T was not mutagenic in bacterial assays, and it did not induce aneuploidy or somatic mutation in vitro. In vivo it did not cause micronuclei in mice or dominant lethal mutations in mice or rats.

Biological. 2,4,5-T degraded in anaerobic sludge by reductive dechlorination to 2,4,5- trichlorophenol, 3,4-dichlorophenol and 4-chlorophenol (Mikesell and Boyd, 1985). An anaerobic methanogenic consortium, growing on 3-chlorobenzoate, metabolized 2,4,5-T to (2,5-dichlorophenoxy)acetic acid at a rate of 1.02 × 10–7 M/hr. The half-life was reported to be 2 days at 37°C (Su?ita et al., 1984). Under aerobic conditions, 2,4,5-T degraded to 2,4,5- trichlorophenol and 3,5-dichlorocatechol which may further degrade to 4-chlorocatechol or cis,cis-2,4-dichloromuconic acid, 2-chloro-4-carboxymethylenebut-2-enolide, chlorosuccinic acid and succinic acid (Byast and Hance, 1975). The cometabolic oxidation of 2,4,5-T by Brevibacterium sp. yielded a product tentatively identified as 3,5-dichlorocatechol (Horvath, 1970). The cometabolism of this compound by Achromobacter sp. gave 3,5-dichloro-2- hydroxymuconic semialdehyde (Horvath, 1970a). Rosenberg and Alexander (1980) reported that 2,4,5-trichlorophenol, the principal degradation product of 2,4,5-T by microbes, was further metabolized to 3,5-dichlorocatechol, 4-chlorocatechol, succinate, cis,cis-2,4-dichlo- romuconate, 2-chloro-4-(carboxymethylene)but-2-enolide and chlorosuccinate.
Soil. 2,4,5-Trichlorophenol and 2,4,5-trichloroanisole were the primary degradation products formed when 2,4,5-T was incubated in soil at 25°C under aerobic conditions. The half-life under these conditions was 14 days (McCall et al., 1981a). When
The half-lives of 2,4,5-T in soil incubated in the laboratory under aerobic conditions ranged from 14 to 64 days with an average of 33 days (Altom and Stritzke, 1973; Foster and McKercher, 1973; Yoshida and Castro, 1975). In field soils, the disappearance
Groundwater . According to the U.S. EPA (1986) 2,4,5-T has a high potential to leach to groundwater .
Photolytic. When 2,4,5-T (10–4 M) in oxygenated water containing titanium dioxide (2 g/L) suspension was irradiated by sunlight (λ ≥340 nm), 2,4,5-trichlorophenol, 2,4,5- trichlorophenyl formate and nine chlorinated aromatic hydrocarbons formed a

Soluble in ethanol (548.2 mg/L), ether (243.2 mg/L), heptane (400 mg/L), xylenes (6.8 g/L), methanol (496 g/L), toluene (7.32 g/L) (quoted, Keith and Walters, 1992).

Crystallise this herbicide from *benzene. [Beilstein 6 III 721.] (CANCER SUSPECT)