Lead poisoning and arsenic exposure have become serious health risks in the past few decades. Lead poisoning or plubism is a well-known toxicological condition, in which its exposure can cause either acute or chronic poisoning. It can also cause several disturbances on normal physiology of humans. The problem of lead poisoning can be seen all over the world, as can arsenic exposure. Arsenic is one of the most toxic and ubiquitously occurring minerals. It is found frequently in rivers and wells in some regions of Argentina and Chile. Arsenic’s toxicity may be acute or chronic and is acquired involuntarily through ingestion of water or food, inhalation and to a lesser degree by percutaneous absorption. Exposure to arsenic in drinking water is related with many health effects that have different in incidences depending on the geographical area. The most evident effects are often related with cancer development, but arsenic can cause alterations on other organs as well. This book examines the potential adverse effects of lead poisoning and arsenic exposure on human health.