Why is 1,2-DCP 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 1,2-DCP has been set at zero because EPA believes this
level of protection would not cause any of the potential health
problems 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 public water supplies must abide by these
regulations.
What are the Health Effects?
Short-term: EPA has found 1,2-DCP to potentially cause the
following health effects when people are exposed to it at levels
above the MCL for relatively short periods of time: damage to the
liver, kidneys, adrenal glands, bladder, and the gastrointestinal
and respiratory tracts.
Long-term: 1,2-DCP has the potential to cause the following effects
from a lifetime exposure at levels above the MCL: the liver,
kidneys, bladder, gastrointestinal tract and the respiratory tract;
cancer.
How much 1,2-DCP is produced and released to the environment?
Production of 1,2-DCP has decreased greatly since a 1980 report of
77 million lbs. Dow Chemical, the only listed producer,
discontinued its production in 1991. It may be released into the
atmosphere or in wastewater during its production or use as an
intermediate in chemical manufacture. There were also significant
releases during its former use as a soil fumigant. It may also
leach from municipal landfills.
From 1987 to 1993, according to EPA's Toxic Chemical Release
Inventory, 1,2-dichloropropane releases to land and water totalled
nearly 104,000 lbs. These releases were primarily from chemical
industries. The largest releases occurred in New York.
What happens to 1,2-DCP when it is released to the environment?
1,2-DCP released to soil will largely evaporate. However, it has
been detected in groundwater. Releases to surface water will also
evaporate, and are not likely to accumulate in aquatic life.
How will 1,2-DCP be Detected in and Removed from My Drinking Water?
The regulation for 1,2-DCP became effective in 1992. 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 1,2-DCP
is present above 0.5 ppb. If it is present above this level, the
system must continue to monitor this contaminant.
If contaminant levels are found to be consistently above the MCL,
your water supplier must take steps to reduce the amount of 1,2-DCP
so that it is consistently below that level. The following
treatment methods have been approved by EPA for removing 1,2-DCP:
Granular activated charcoal in combination with Packed Tower
Aeration.
How will I know if 1,2-DCP is in my drinking water?
If the levels of 1,2-DCP 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 ppm
1,2-DCP Releases to Water and Land, 1987 to 1993 (in pounds):
| Water | Land |
TOTALS (in pounds) | 98,504 | 5,470 |
Top Five States |
---|
NY | 30,000 | 3,205
|
LA | 25,586 | 260
|
VA | 14,629 | 250
|
TX | 12,290 | 1,206
|
NJ | 10,463 | 0
|
Major Industries |
---|
Alkalies, chlorine | 37,297 | 1,216
|
Photographic equip. | 30,000 | 3,205
|
Gum, wood chemicals | 14,629 | 250
|
Plastics, resins | 10,463 | 0
|
Misc. Indust. Organics | 4,793 | 250
|
* 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