This is a fact sheet 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 Chlordane and how is it used?
Chlordane is a viscous liquid, colorless to amber, with a slight
chlorine-like aromatic odor. It was used on corn, citrus, deciduous
fruits and nuts, vegetables; for home, garden and ornamentals; lawns,
turf, ditchbanks and roadsides. It was applied directly to soil or
foliage to control a variety of insect pests including parasitic
roundworms and other nematodes, termites, cutworms, chiggers,
leafhoppers. The only commercial use of chlordane products still
permitted is for fire ant control in power transformers.
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:
Tat Chlor 4
Gold Crest C-100
Why is Chlordane 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
The MCLG for chlordane 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 2 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 chlordane to potentially cause the following
health effects when people are exposed to it at levels above the MCL for
relatively short periods of time: central nervous system effects -
including irritability, excess salivation, labored breathing, tremors,
convulsions, deep depression - and blood system effects such as anemia
and certain types of leukemia.
Long-term: Chlordane has the potential to cause the following
effects from a lifetime exposure at levels above the MCL: damage to
liver, kidneys, heart, lungs, spleen and adrenal glands; cancer.
How much Chlordane is produced and released to the environment?
Chlordane has been released into the environment primarily from its
application as an insecticide. The amount of chlordane used annually in
the US prior to 1983 was estimated in 1985 to be greater that 3.6
million pounds. As of April 14, 1988, however, all commercial use of
chlordane in the US has been canceled.
What happens to Chlordane when it is released to the environment?
Chlordane may persist for long periods of time in air, soil and water.
Though chlordane tends to adhere to soil, its detection in various
groundwaters in NJ and elsewhere indicates that it can leach to
groundwater. It is only very slowly broken down by microbes. Chlordane
has been detected in air samples in remote areas such as over the
Pacific and Atlantic Oceans, and in the Arctic.
Chlordane has a great tendency to accumulate in aquatic organisms, but
there is evidence that this is reversible once exposure is stopped.
How will Chlordane be detected in and removed from my drinking
The regulation for chlordane 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 chlordane is present
above 0.2 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 chlordane so
that it is consistently below that level. The following treatment
methods have been approved by EPA for removing chlordane: granular
How will I know if Chlordane is in my drinking water?
If the levels of chlordane exceed the MCL, 2 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.
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).
Drinking Water Standards:
Note: This fact sheet is part of a larger publication
adapted from U.S. EPA publication: EPA National Primary Drinking Water
Mcl: 2 ppb (parts per billion)