A ferrous wheel.
Benzene is one of the mostly widely produced chemicals, ranking in the top 20 by volume. It occurs naturally in crude oil and gasoline, and is produced in volcanoes and wildfires. It breaks down quickly in the air, however in water and soil it can be extremely persistent. It is found in 1,000 of the 1,684 National Priority List sites as designated by the EPA.
Benzene is an effective non-polar solvent, and was once used to remove caffeine from coffee beans. It is used in the synthesis of plastics, rubbers, lubricants, dyes, detergents, drugs, and pesticides. Exposure generally occurs through the air. Vapors from glues, paints, furniture waxes, motor vehicles, and industrial emissions are the most common sources.
Breathing benzene can cause rapid heart rate, tremors, confusion, and dizziness. High levels can cause death. It is a known human carcinogen. Benzene can cause acute myelogenous leukemia, a cancer of the blood forming organs.
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