What is benzene?
Benzene is a highly flammable liquid that is colorless, a hydrocarbon and is an aromatic compound that has a sweet odor. It evaporates into the air very quickly and dissolves slightly in water. It is formed from both natural processes and human activities. Benzene is lighter than water and is almost insoluble in it.
Benzene is widely used in the United States; it ranks in the top 20 chemicals for production volume. Benzene is also a natural part of crude oil, gasoline, and cigarette smoke. Because benzene is found in cigarettes, women who smoke pass even more benzene to their children through their breast milk.
What happens to benzene when it enters the environment?
In general, Benzene comes from a point source such as an industrial plant where it is used as a starter to help create other chemicals. It is used to make plastics, synthetic detergent, nylon, synthetic rubber, styrofoam, and aniline dyes. The benzene ring arrangement is also found in fuel for internal combustion engines, in benzaldehyde (an oil made from bitter almonds), and in TNT, aspirin, oil of wintergreen, and some amino acids. Benzene is sometimes called "benzol" when found in these substances. Every time a gasoline pump is activated benzene is discharged into the air. Benzene is also released into the environment as a result of natural occurrences such as volcanoes and forest fires.
How might I be exposed to benzene?
- Outdoor air contains low levels of benzene from tobacco smoke, automobile service stations, exhaust from motor vehicles, and industrial emissions.
- Indoor air generally contains higher levels of benzene from products that contain it such as glues, paints, furniture wax, and detergents.
- Air around hazardous waste sites or gas stations will contain higher levels of benzene.
- Leakage from underground storage tanks or from hazardous waste sites containing benzene can result in benzene contamination of well water.
- People working in industries that make or use benzene may be exposed to the highest levels of it.
How can benzene affect my health?
Breathing lower levels of benzene over a long period of time can harm blood cells and damage bone marrow. This can lead to anemia of excessive bleeding or cancer of the white blood cells (leukemia). Breathing higher levels (50,000 times the average levels) can cause temporary drowsiness, dizziness, rapid heart rate, headaches,tremors, confusion, and unconsciousness. Brief exposures of 5-10 minutes to benzene in air at very high levels (500,000 times the average levels) can cause death.
Eating or drinking high levels of benzene can cause:
- Vomiting or irritation of the stomach.
- Dizziness, sleepiness, or convulsions.
- Rapid heart rate, coma, and death.
- Direct contact with the skin may cause redness and sores.
- It can also damage your eyes.
Animal studies indicate that benzene may damage genes and may affect the ability to have healthy children. Benzene affects the circulatory system by increasing heart rate. Benzene affects the digestive system by causing vomiting or irritation of the stomach. Benzene also harms the immune system. This increases chances of infection and reduces the body's ability to fight off diseases.
The federal government has made recommendations to protect human health. The Environmental Protection Agency (EPA) sets a maximum permissible level of benzene in drinking water at 5 parts of benzene per billion parts of water (5 ppb) per day for a lifetime of exposure. EPA sets a goal of 0 ppb benzene in drinking water and in rivers and lakes. The maximum permissible level of benzene in water for short-term exposures (10 days) for children is 235 ppb. We are pleased to report to you that the test results for benzene in the UAF drinking water over the past 10 years have consistently shown that the benzene level is below the detection limit of 0.02 mg/l (milligrams per liter) or 2 parts per billion.
The water any water system delivers to you must meet strict rules of purity. To help you understand better what a part per million and part per billion really are:
- One part per million, or one milligram per liter, would be equal to putting ONE drop of water, or any contaminant, into 10 gallons of water.
- One part per billion, or one microgram per liter, would be equal to adding one drop of water to a 10,000 gallon swimming pool. (A part per billion is 1,000 times smaller than a part per million.)
We are very confident that there is 0 ppb of benzene in the water being produced at the UAF water treatment plant because of the extensive treatment being done to produce a high quality drinking water and from the bi-weekly samples being taken, however, we can only report that the level of Benzene is below the laboratories detection limit.