Consumer Factsheet on: BENZENE
List of Contaminants
As part of the Drinking Water and Health pages, this fact
sheet is part of a larger publication:
National Primary Drinking Water Regulations
This is a factsheet about a chemical that may be found in some
public or private drinking water supplies. It may cause health
problems if found in amounts greater than the health standard set
by the United States Environmental Protection Agency (EPA).
What is Benzene and how is it used?
Benzene is a clear, colorless aromatic liquid. It is highly
flammable. The greatest use of benzene is as a building block for
making plastics, rubber, resins and synthetic fabrics like nylon
and polyester. Other uses include: as a solvent in printing,
paints, dry cleaning, etc.
The list of trade names given below may help you find out whether
you are using this chemical at home or work.
Trade Names and Synonyms:
Benzol 90
Pyrobenzol
Polystream
Coal naphtha
Phene
Why is Benzene being Regulated?
In 1974, Congress passed the Safe Drinking Water Act. This law
requires EPA to determine safe levels of chemicals in drinking
water which do or may cause health problems. These non-enforceable
levels, based solely on possible health risks and exposure, are
called Maximum Contaminant Level Goals.
The MCLG for benzene has been set at zero because EPA believes this
level of protection would not cause any of the health effects
described below.
Based on this MCLG, EPA has set an enforceable standard called a
Maximum Contaminant Level (MCL). MCLs are set as close to the MCLGs
as possible, considering the ability of public water systems to
detect and remove contaminants using suitable treatment
technologies.
The MCL has been set at 5 parts per billion (ppb) because EPA
believes, given present technology and resources, this is the
lowest level to which water systems can reasonably be required to
remove this contaminant should it occur in drinking water.
These drinking water standards and the regulations for ensuring
these standards are met, are called National Primary Drinking Water
Regulations. All community water supplies must abide by these
regulations.
What are the Health Effects?
Short-term: EPA has found benzene to potentially cause the
following health effects when people are exposed to it at levels
above the MCL for relatively short periods of time: temporary
nervous system disorders, immune system depression, anemia.
Long-term: Benzene has the potential to cause the following effects
from a lifetime exposure at levels above the MCL: chromosome
aberrations, cancer.
How much Benzene is produced and released to the environment?
Production of benzene has increased: from about 9.9 billion lbs. in
1984 to over 12 billion lbs. in 1993.
Benzene is released to air primarily from fumes and exhaust
connected with its use in gasoline. Other sources are fumes from
its production and use in manufacturing other chemicals. In
addition, there are discharges into water from industrial effluents
and losses during spills.
From 1987 to 1992, according to the Toxics Release Inventory,
releases of benzene to water and land totalled over 2 million lbs.
These releases were primarily from petroleum refining industries,
with the greatest releases occurring in Texas.
What happens to Benzene when it is released to the environment?
If benzene is released to soil, it will either evaporate very
quickly or leach to groundwater. It can be broken down by some soil
microbes. It may also be degraded in some ground waters. If benzene
is released to surface water, most of it should evaporate within a
few hours. Though it does not degrade by reacting with water, it
may be degraded by microbes. It is not likely to accumulate in
aquatic organisms.
How will Benzene be Detected in and Removed from My Drinking Water?
The regulation for benzene became effective in 1989. Between 1993
and 1995, EPA required your water supplier to collect water samples
every 3 months for one year and analyze them to find out if benzene
is present above 0.5 ppb. If it is present above this level, the
system must continue to monitor the benzene levels.
If contaminant levels are found to be consistently above the MCL,
your water supplier must take steps to reduce the amount of benzene
so that it is consistently below that level. The following
treatment methods have been approved by EPA for removing benzene:
Granular activated charcoal in combination with Packed Tower
Aeration.
How will I know if Benzene is in my drinking water?
If the levels of benzene exceed the MCL, 5 ppb, the system must
notify the public via newspapers, radio, TV and other means.
Additional actions, such as providing alternative drinking water
supplies, may be required to prevent serious risks to public
health.
Drinking Water Standards:
Mclg: zero
Mcl: 5 ppb
Benzene Releases to Water and Land, 1987 to 1993 (in pounds):
| Water | Land |
TOTAL | 564,546 | 1,539,385 |
Top Six States* |
---|
TX | 1,436 | 1,135,994
|
AL | 199,642 | 0
|
LA | 137,599 | 4,347
|
CO | 0 | 40,793
|
NM | 0 | 38,199
|
IL | 3 | 34,110
|
Major Industries* |
---|
Petroleum refining | 32,411 | 1,049,800
|
Primary Metal Ind. | 133,339 | 18,078
|
Industrial chemicals | 73,000 | 250,103
|
Alkalies, chlorine | 122,240 | 0
|
* Water/Land totals only include facilities with releases greater
than a certain amount - usually 1000 to 10,000 lbs.
Learn more about your drinking water!
EPA strongly encourages people to learn more about their drinking
water, and to support local efforts to protect and upgrade the
supply of safe drinking water. Your water bill or telephone books
government listings are a good starting point.
Your local water supplier can give you a list of the chemicals they
test for in your water, as well as how your water is treated.
Your state Department of Health/Environment is also a valuable
source of information.
For help in locating these agencies or for information on drinking
water in general, call: EPAs Safe Drinking Water Hotline: (800)
426-4791.
For additional information on the uses and releases of chemicals in
your state, contact the: Community Right-to-Know Hotline: (800) 424-9346.
List of Contaminants
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