inorganic arsenic

Inorganic arsenic refers to arsenic compounds where arsenic binds with elements such as sulfur, oxygen, and chlorine rather than carbon-containing molecules. The most common forms are **arsenite** (trivalent arsenic, As³⁺) and **arsenate** (pentavalent arsenic, As⁵⁺), with arsenic trioxide (As₂O₃) being the most prevalent form in air. Inorganic arsenic compounds are **highly toxic** and classified as **confirmed human carcinogens** by multiple health agencies including IARC, EPA, and DHHS. The toxic mechanisms involve: (1) arsenite binding to sulfhydryl groups in critical enzymes, disrupting cellular respiration and ATP formation, particularly affecting pyruvate dehydrogenase in the citric acid cycle, and (2) arsenate substituting for phosphate in biochemical reactions, causing rapid hydrolysis of high-energy bonds and uncoupling oxidative phosphorylation. Historically used extensively in pesticides, wood preservatives (CCA-treated wood), and medicine, most agricultural uses have been banned in the United States due to toxicity concerns. However, **arsenic trioxide** has been reintroduced as a pharmaceutical agent for treating **acute promyelocytic leukemia**. Inorganic arsenic is also released into the environment through mining, smelting operations, coal combustion, and is used in semiconductor production (as gallium arsenide), alloys, and glass manufacturing.

Other names

arsenitearsenatearsenic trioxideAs2O3As-2O3As 2O3arsenic acidwhite arsenic