EPN

Description

EPN is a light yellow crystalline solid with anaromatic odor (as a pesticide) or a brown liquid above36℃. Molecular weight = 323.32; Freezing/Meltingpoint = 36℃; Vapor pressure = 3.4 * 10 -7 mmHg at 20℃.Hazard Identification (based on NFPA-704 M RatingSystem): Health 4, Flammability 1, Reactivity 0. Insolublein water.

Chemical properties

Light-yellow crystals. Insoluble in water; soluble in most organic solvents. Decomposes in alkaline solutions.

Chemical properties

EPN is a light yellow crystalline solid with an aromatic odor (as a pesticide) or a brown liquid above 36°C

Physical properties

Yellow to brown crystalline powder with an aromatic-like odor.

The Uses of EPN

EPN is used to control chewing insects, especially lepidopterous larvae in cotton, rice, fruit and vegetables.

The Uses of EPN

Insecticide; acaricide.

The Uses of EPN

Acaricide; insecticide

Definition

ChEBI: EPN is an organic phosphonate, a phosphonic ester and an organothiophosphate insecticide. It has a role as an EC 3.1.1.7 (acetylcholinesterase) inhibitor, an acaricide and an agrochemical.

General Description

Light yellow crystalline powder with an aromatic odor. Used as an insecticide for cotton and an acaricide.

Air & Water Reactions

Insoluble in water. Hydrolyzed by alkali [EPA, 1998].

Reactivity Profile

Organophosphates, such as EPN, 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.

Hazard

A cholinesterase inhibitor, absorbed by skin, use may be restricted. Questionable carcinogen.

Health Hazard

EPN may be fatal if swallowed. It is poisonous if inhaled and extremely hazardous by skin contact. Repeated exposure may, without symptoms, be increasingly hazardous. The estimated fatal oral dose is 0.3 grams for a 150 lb. (70 kg) person.

Fire Hazard

(Non-Specific -- Organophosphorus Pesticide, n.o.s.) EPN may burn but does not ignite readily. Container may explode in heat of fire. Fire and runoff from fire control water may produce irritating or poisonous gases. Avoid strong oxidizers. Hydrolyzed by alkali.

Agricultural Uses

Insecticide: Banned for use in the EU. All registered uses of EPN in the U.S. were canceled by the U.S. EPA on August 31, 1988. Effective June 9, 1993, the U.S. EPA announced the revocation of all tolerances for residues of the insecticide

Trade name

NIAGARA®[C]; PIN®; SANTOX®; TRIPLE KILL T®[C]; VETO®[C]

Safety Profile

Poison by ingestion, skin contact, and intraperitoneal routes. An experimental teratogen. A cholinesterase inhibitor. Ths material is extremelyhazardous on contact with skin, inhalation, or ingestion. A highly toxic insecticide. When heated to decomposition it emits highly toxic fumes of SOx, POx, NOx, and phosphme. See also PARATHION, NITRO COMPOUNDS OF AROMATIC HYDROCARBONS, PHOSPHINE, and SULFIDES

Potential Exposure

EPN is used in preparation of emulsifiable, granular or wettable powder insecticides for cotton. A potential danger to those involved in the manufacture, formulation and application of this material.

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 skin is 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

Biological. From the first-order biotic and abiotic rate constants of EPN in estuarine water and sediment/water systems, the estimated biodegradation half-lives were 6.2 and 9.2 days, respectively (Walker et al., 1988).
Soil. Though no products were reported, the half-life in soil is 15–30 days (Hartley and Kidd, 1987).
Photolytic. EPN may undergo direct photolysis since the insecticide showed some absorption when a 1,4-dioxane was irradiated with UV light (l >290 nm) (Gore et al., 1971).
Chemical/Physical. On heating, EPN is converted to the S-ethyl isomer (Worthing and Hance, 1991). Releases toxic fumes of phosphorus, nitrogen and sulfur oxides when heated to decomposition (Sax and Lewis, 1987; Lewis, 1990). Rapidly hydrolyzed in alkaline solutions to p-nitrophenol, alcohol and benzene thiophosphoric acid (Sittig, 1985).

Metabolic pathway

EPN is degraded and deactivated in soil, plants and animals by a series of hydrolytic, dealkylation and oxidative desulfuration steps, ultimately to give phenylphosphonate. The metabolic pathway may or may not proceed via activation to the oxon, which is not usually detected in appreciable quantities as it metabolically unstable. A detoxification reaction via reduction of the nitro group to afford amino-EPN has been shown to take place in anaerobic soil, bacteria and animals. Uncommonly for organophosphates, hydroxylation of the phenyl ring also occurs in rats and hens.

storage

Color Code—Blue: Health Hazard/Poison: Storein a secure poison location. Prior to working with EPN youshould be trained on its proper handling and storage. Storein tightly closed containers in a cool, well-ventilated areaaway from oxidizers.

Shipping

UN2783 Organophosphorus pesticides, solid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials. UN2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. UN3018 Organophosphorus pesticides, liquid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.

Degradation

EPN is hydrolysed by alkali to yield 4-nitrophenol (2). The half-lives at pH values 4 and 7 were 70 days and 22 days, respectively. When heated in a sealed tube it was converted to the isomeric S-ethyl O-4-nitrophenyl phenylphosphonothioate (3) (PM).

Incompatibilities

Contact with oxidizers may cause the release of phosphorous oxides. Contact with strong reducing agents, such as hydrides; may cause the formation of flammable and toxic phosphine gas. Contact with alkalies causes decomposition (hydrolysis) producing p-nitrophenol.

Waste Disposal

EPN plant wastes are treated by preaeration, activated sludge treatment; recycle, chlorination and final polishing where additional natural biological stabilization occurs. EPN is also relatively rapidly hydrolyzed in alkaline solution to benzene thiophosphoric acid; alcohol and p-nitrophenol and soil burial with alkali may be used. For large quantities, however, incineration is recommended. 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.