LEAD ARSENATE

Description

Lead arsenate appears as odourless white heavy powder and practically is insoluble in water. It is not combustible and emits irritating or toxic fumes (or gases) in a fire. Lead arsenate is currently used as a growth regulator on grape fruit crop. A large bulk of lead arsenate is also used annually to control cockroaches, silverfish, crickets, earthworms, and other soil-inhabiting insects on golf greens and lawns and on airport turf adjoining runways to reduce bird hazard related to earthworm. Lead arsenate is quite stable and readily accumulates in soils either as a result of use in specific soil treatments or foliar application. Lead arsenate insecticide was used in many countries, including Australia, Canada, New Zealand, and the United States. It was used for insect pests on apples and other fruit tree, garden crops and turf grasses, on rubber and coffee trees, and for mosquito abatement in cattle dips. All insecticidal uses of lead arsenate in the United States were officially banned on August 1, 1988 (U.S. EPA, 1988), with a comment that all registrations for insecticidal use had lapsed before that date. In Australia, use of lead arsenate decreased after the introduction of DDT in 1950, and it has not been used on exported crops since 1983.

Chemical properties

Lead arsenate is an odorless, white, heavy powder. It is not combustible and emits irritating or toxic fumes (or gases) in a fi re. Lead arsenate enters the body by inhalation, or from contaminated food and beverages. It is used to make insecticides.

Chemical properties

Lead arsenate is an odorless, heavy, white powder, or crystals.

The Uses of LEAD ARSENATE

Lead arsenate [Pb3(AsO4)4] is a toxic commercial insecticide and herbicide.

The Uses of LEAD ARSENATE

As constituent of various insecticides for larvae of gypsy moth, boll weevil, etc.

The Uses of LEAD ARSENATE

Insecticide; veterinarian treatment as a teniacide and insecticide.

Definition

ChEBI: Lead arsenate is an inorganic lead salt composed from lead(2+) and arsenate dianion. It was widely used in the United States in the 1950's as an insecticide to control pests in fruit orchards, specifically apples and cherries. It has a role as an insecticide, a plant growth regulator and a rodenticide. It contains a lead(2+) and an arsenate(2-).

Production Methods

Lead arsenate is produced mainly from lead acetate, lead nitrate, and lead oxide and disodium arsenate.The direct reaction of arsenic acid with litharge in the presence of nitric acid gives a dilead arsenate. Com mercial lead arsenates contain mostly PbHAsO4 along with varying amounts of Pb3(AsO4)2. Accordingly, their lead content is higher and their As2O3 content lower than the levels calculated for PbHAsO4.

Health Hazard

Exposures to lead arsenate occur in work areas and it is absorbed into the body by inhalation of its dust and by ingestion. It is irritating to the eyes, the skin, and the respiratory tract, and causes adverse effects on the gastrointestinal tract, nervous system, kidneys, liver, and blood. Accidental ingestion of lead arsenate in the workplace causes cough, sore throat, abdominal pain, diarrhea, drowsiness, headache, nausea, vomiting, muscular cramp, constipation, excitation, and disorientation in the worker.

Potential Exposure

Used as an insecticide, herbicide, and in manufacture of drugs; veterinary tapeworm medicine. Incompatibilities: Violent reactions occur from contact with oxidizers, chemically active metals; strong acids. Acids and acid mists cause the release of arsine, a deadly gas. Decomposes above 270C forming toxic fumes including arsenic and lead compounds

Shipping

UN1617 Lead arsenates, Hazard Class: 6.1; Labels: 6.1-Poisonous materials

Incompatibilities

Used as an insecticide, herbicide, and in manufacture of drugs; veterinary tapeworm medicine. Incompatibilities: Violent reactions occur from contact with oxidizers, chemically active metals; strong acids. Acids and acid mists cause the release of arsine, a deadly gas. Decomposes above 270C forming toxic fumes including arsenic and lead compounds

Waste Disposal

Long- term storage in large, weatherproof, and sift-proof storage bins or silos; may be disposed of by conversion to soluble salt, such as chloride, precipitation as sulfide and return to supplier