Difference between revisions of "Benzene"
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[[Anthropogenic]] releases of benzene into the atmosphere result mainly from environmental tobacco smoke, automobile exhaust, automobile refuelling operations, and industrial emissions. | [[Anthropogenic]] releases of benzene into the atmosphere result mainly from environmental tobacco smoke, automobile exhaust, automobile refuelling operations, and industrial emissions. | ||
− | Benzene has a moderate water solubility of 1,78 g/l, but is highly volatile and can rapidly evaporate from surface waters to the atmosphere. It has a low [[adsorption]] to sediments or soils and will rapidly be removed from them to surface and ground water and the atmosphere. In the atmosphere it will be degraded within 8 days. | + | Benzene has a moderate water solubility of 1,78 g/l, but is highly volatile and can rapidly evaporate from surface waters to the atmosphere. It has a low [[adsorption]] to sediments or soils and will rapidly be removed from them to surface and ground water and the atmosphere. In the atmosphere it will be degraded within 8 days, in water it takes 16 days to degrade it to half of its original concentration . |
It has a low tendency to [[bioaccumulation|bioaccumulate]], concentrations in goldfish are typically only 4 times higher than those in the environment, and is not considered to [[biomagnification|biomagnify]] though [[food chain|food chains]]. | It has a low tendency to [[bioaccumulation|bioaccumulate]], concentrations in goldfish are typically only 4 times higher than those in the environment, and is not considered to [[biomagnification|biomagnify]] though [[food chain|food chains]]. | ||
+ | <ref name = atsdr>[http://www.atsdr.cdc.gov/toxprofiles/tp3.pdf U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES August 2007 TOXICOLOGICAL PROFILE FOR BENZENE] </ref> | ||
+ | The most sensitive crustaceans start dying at concentrations above 3.3 mg/l although most species tolerate concentrations above 120 mg/l, the most sensitive fish at concentrations above 4.9 mg/l, although most species tolerate concentrations above 100 mg/l. | ||
+ | Concentrations in air typically range between 0.3 ppb and 159 ppb. The highest measured concentration of benzene in marine waters is 315 µg/l. | ||
− | http://www.atsdr.cdc.gov/toxprofiles/tp3.pdf | + | <ref name = atsdr>[http://www.atsdr.cdc.gov/toxprofiles/tp3.pdf U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES August 2007 TOXICOLOGICAL PROFILE FOR BENZENE] </ref> |
Revision as of 13:20, 13 August 2009
Definition of benzene:
Benzene is a colourless liquid with a sweet odor. It evaporates into the air very quickly and dissolves slightly in water. It is highly flammable and is formed from both natural processes and human activities. [1]
This is the common definition for benzene, other definitions can be discussed in the article
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Notes
Benzene is widely used in the United States; it ranks in the top 20 chemicals for production volume. Some industries use benzene to make other chemicals which are used to make plastics, resins, and nylon and synthetic fibers. Benzene is also used to make some types of rubbers, lubricants, dyes, detergents, drugs, and pesticides. Natural sources of benzene include volcanoes and forest fires. Benzene is also a natural part of crude oil, gasoline, and cigarette smoke.[1]
Anthropogenic releases of benzene into the atmosphere result mainly from environmental tobacco smoke, automobile exhaust, automobile refuelling operations, and industrial emissions.
Benzene has a moderate water solubility of 1,78 g/l, but is highly volatile and can rapidly evaporate from surface waters to the atmosphere. It has a low adsorption to sediments or soils and will rapidly be removed from them to surface and ground water and the atmosphere. In the atmosphere it will be degraded within 8 days, in water it takes 16 days to degrade it to half of its original concentration .
It has a low tendency to bioaccumulate, concentrations in goldfish are typically only 4 times higher than those in the environment, and is not considered to biomagnify though food chains. [2]
The most sensitive crustaceans start dying at concentrations above 3.3 mg/l although most species tolerate concentrations above 120 mg/l, the most sensitive fish at concentrations above 4.9 mg/l, although most species tolerate concentrations above 100 mg/l.
Concentrations in air typically range between 0.3 ppb and 159 ppb. The highest measured concentration of benzene in marine waters is 315 µg/l.
[2]