Lead arsenate

Lead arsenate is an inorganic compound that is used as an insecticide. It is a colorless, odorless solid that is not very soluble in water. Its chemical formula is PbHAsO4.

History

Lead arsenate was first used as an insecticide in the United States in the late 19th century. It was developed as a replacement for Paris Green, another arsenic-based insecticide that was found to be harmful to plants. Lead arsenate was widely used in the early 20th century in the production of apples and other fruit crops.

Production

Lead arsenate is produced by reacting lead(II) oxide with arsenic acid. The reaction produces lead arsenate and water. The lead arsenate is then filtered out of the solution and dried.

Use

Lead arsenate is used as an insecticide, particularly against the codling moth, which is a major pest of apple orchards. It is also used against other pests, such as the gypsy moth and the Japanese beetle.

Health effects

Exposure to lead arsenate can cause a variety of health problems. Ingestion or inhalation can lead to arsenic poisoning, which can cause symptoms such as nausea, vomiting, diarrhea, and abdominal pain. Long-term exposure can lead to more serious health problems, such as cancer and damage to the nervous system.

Environmental impact

Lead arsenate is a persistent pesticide, meaning it does not break down easily in the environment. This can lead to contamination of soil and water. It can also be harmful to non-target organisms, such as birds and beneficial insects.

Regulation

Due to its toxicity and environmental impact, the use of lead arsenate has been heavily regulated. In the United States, its use was phased out in the 1980s. However, it is still used in some countries.

See also

• Arsenic
• Lead
• Insecticide
• Pesticide