| hazards summary | Arsenic is a naturally occurring element widely distributed in the earth's crust. In the environment, arsenic is combined with oxygen, chlorine, and sulfur to form inorganic arsenic compounds. Arsenic in animals and plants combines with carbon and hydrogen to form organic arsenic compounds. Inorganic arsenic compounds are mainly used to preserve wood. Copper chromated arsenic (CCA) is used to make "pressure-treated" lumber. CCA is no longer used in the U.S. for residential uses. it is still used in industrial applications. Organic arsenic compounds are used as pesticides, primarily on cotton plants.Arsenic, a naturally occurring element, is found throughout the environment. For most people, exposure to arsenic, including to inorganic arsenic compounds, occurs through their diet. Acute (short-term), high-level inhalation exposure to inorganic arsenic has resulted in respiratory effects (cough, dyspnea, chest pain), gastrointestinal effects (nausea, diarrhea, abdominal pain), and central and peripheral nervous system effects. Chronic (long-term) inhalation exposure to inorganic arsenic in humans is associated with skin, cardiovascular, and neurological effects. Acute oral exposure to inorganic arsenic has resulted in effects on the digestive tract, respiratory tract, central nervous system (CNS), cardiovascular system, liver, and blood and has resulted in death. Chronic oral exposure to elevated levels of inorganic arsenic has resulted in gastrointestinal effects, anemia, peripheral neuropathy, skin lesions, hyperpigmentation, and liver and kidney damage in humans. EPA has concluded that inorganic arsenic is a human carcinogen. Evidence from human studies suggests that exposure to inorganic arsenic by inhalation may result in lung cancer, while exposure by ingestion may result in nonmelanoma skin cancer and bladder, kidney, liver, and lung cancers.Except for the electronics industry, the commercial use of arsenic is declining. Skin lesions, peripheral neuropathy, and anemia are the hallmarks of chronic poisoning. Chronic exposure is associated with lung, liver, and skin cancer. Liver function tests may be abnormal after chronic poisoning. Nasal septum perforation after dust exposure in the workplace was reported in the past. Encephalopathy, after both acute and chronic exposure, has been reported. In chronic toxicity, the kidney is not a major target organ. The evidence that arsenic is a skin and lung occupational carcinogen is strong. The evidence for liver cancer (angiosarcoma) is suggestive. Incrimination of arsenic toxicity in noncirrhotic portal hypertension (i.e., hepatoportal sclerosis) is convincing. The multiple cases that have been reported for patients treated with arsenical preparations and the epidemiologic association of noncirrhotic portal hypertension with intake of arsenic-contaminated drinking water are strongly suggestive. There is limited positive data for arsenic causing spontaneous abortions in humans and strong positive data for causing testicular damage, birth defects, and fetal loss in animals. Arsenic salts are irritants, but can be skin sensitizers. In order of decreasing toxicity are inorganic trivalent, organic trivalent, inorganic pentavalent, and organic pentavalent compounds. Elemental arsenic is rare in nature and rarely encountered as a toxic substance. Ingestion of 100-300 mg soluble trivalent arsenic such as sodium arsenite can cause fatal hemorrhagic gastroenteritis and shock. Effects of arsenic poisoning after ingestion may include shock and acute renal failure. See Arsenic Exposure, Assessment, Toxicity, Diagnosis, and Management. See the disease, Arsenic, chronic toxic effect. |