Barium arsenite is a white, crystalline powder composed of barium and arsenic. Historically, it was used as a pesticide to control agricultural pests, but its use has largely been discontinued due to its high toxicity and environmental risks. Exposure to barium arsenite can result in various health problems, including gastrointestinal distress, skin irritation, respiratory issues, and, in severe cases, fatal poisoning. Environmental concerns, such as soil and water contamination, have been raised due to its long-term effects on ecosystems.