Arsenic through the gastrointestinal tract

Chronic exposure to inorganic arsenic (As) through the diet is considered to be a worldwide health problem. Epidemiological and mechanistic studies have evidenced its toxicity in different types of target cells, tissues, or organs. However, studies related to the gastrointestinal tract are scarce. For a long time, the digestive tract was not considered to participate in the metabolic processes of As, nor has it been regarded as a possible target of its toxicity. Nevertheless, the literature on this subject has grown over the last decade, and there are now data to suggest that events take place within the gastrointestinal lumen that condition the systemic toxicity of this metalloid, particularly of inorganic As. This chapter intends to compile all the information on this issue and describe the gastrointestinal tract as a key element in the mechanisms of toxicity of ingested As.