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Revised June 1996
Chlordane
Trade and Other Names:
In addition to chlordane, common names have included chlordan and
clordano. Trade names include Belt, Chlor Kil, Chlortox,
Corodane, Gold Crest C-100, Kilex Lindane, Kypchlor, Niran,
Octachlor, Synklor, Termex, Topiclor 20, Toxichlor, and Velsicol
1068.
Regulatory Status:
Because of concern about the risk of cancer, use of chlordane was
canceled in April, 1988. Between 1983 and 1988 the only permitted
use for chlordane was for control of subterranean termites.
Chlordane is no longer distributed in the U.S. The only
commercial use still permitted is for fire ant control in power
transformers. It was classified toxicity class II - moderately
toxic. Products containing chlordane bear the Signal Word
WARNING.
Chemical Class:
organochlorine
Introduction:
Chlordane is a persistent organochlorine insecticide. It kills
insects when ingested and on contact. Formulations include dusts,
emulsifiable concentrates, granules, oil solutions, and wettable
powders.
Formulation:
Formulations include dusts, emulsifiable concentrates, granules,
oil solutions, and wettable powders.
Toxicological Effects:
- Acute toxicity: Chlordane is moderately
to highly toxic through all routes of exposure. Symptoms
usually start within 45 minutes to several hours after
exposure to a toxic dose. Convulsions may be the first
sign of poisoning, or they may be preceded by nausea,
vomiting, and gut pain. Initially, poisoning victims may
appear agitated or excited, but later they may become
depressed, uncoordinated, tired, or confused. Other
symptoms reported in cases of chlordane poisoning include
headaches, dizziness, vision problems, irritability, and
weakness or muscle twitching. In severe cases,
respiratory failure and death may occur. Complete
recovery from a toxic exposure to chlordane is possible
if proper medical treatment is administered [2,20].
Chlordane is very irritating to the skin and eyes
[21,22]. Chlordane affects liver function, so many
interactions between medicines and this pesticide may
occur. Among these are decreased effectiveness of
anticoagulants, phenylbutazone, chlorpromazine, steroids,
birth control pills, and diphenhydramine. Increased
activity of thyroid hormone may also occur [23]. The oral
LD50 for chlordane in rats is 200 to 700 mg/kg, in mice
is 145 to 430 mg/kg, in rabbits is 20 to 300 mg/kg, and
in hamsters is 1720 mg/kg [2,9]. The dermal LD50 in
rabbits is 780 mg/kg, and in rats is 530 to 690 mg/kg
[9,17]. The 4-hour inhalation LD50 in cats is 100 mg/L
[17,24].
- Chronic toxicity: Liver lesions and
changes in blood serum occurred in rats exposed to 1.0
mg/L chlordane in air. Increased kidney weights occurred
in rats exposed to 10 mg/L. For monkeys, increased liver
weight occurred at 10 mg/L [20]. Animal studies have
shown that consumption of chlordane has caused damage to
the liver and the central nervous system [20,21]. In a
2-year feeding study with rats, a near-lethal dose of 300
mg/kg/day produced eye and nose hemorrhaging, severe
changes in the tissues of the liver, kidney, heart,
lungs, adrenal gland, and spleen. In this same study, no
adverse effects were observed in rats fed 5 mg/kg/day. In
a long-term feeding study with mice, body weight loss,
increased liver weight, and death occurred at doses of 22
to 63.8 mg/kg/day. Dogs fed doses of 15 and 30 mg/kg/day
exhibited increased liver weights [2,20].
- Reproductive effects: Chlordane has been
shown to affect reproduction in test animals. Fertility
was reduced by about 50% in mice injected with chlordane
at 22 mg/kg once a week for 3 weeks [25]. The data
suggest that reproductive effects in humans are unlikely
at expected exposure levels.
- Teratogenic effects: No teratogenic
effects were observed in rats born to dams fed chlordane
at 5 to 300 mg/kg/day for 2 years [20]. It is unlikely
that chlordane will cause teratogenic effects in humans.
- Mutagenic effects: Chlorinated
hydrocarbon insecticides (such as chlordane) are
generally not mutagenic [2]. It was reported that 15 out
of 17 mutagenicity tests performed with chlordane have
shown no mutagenic effects [25]. Thus, chlordane is
weakly or nonmutagenic.
- Carcinogenic effects: The EPA has
classified that chlordane as a probable human carcinogen.
Chlordane has caused liver cancer in mice given doses of
30 to 64 mg/kg/day for 80 weeks [24]. However, a study
was done on workers at a manufacturing plant who had been
exposed to chlorinated hydrocarbons for 34 years,
including chlordane. No increase in any type of cancer
was found [24,25].
- Organ toxicity: In clinical studies of
acute or chronic exposure to chlordane, the effects most
frequently observed are central nervous system effects,
liver effects, and blood disorders [25]. Chronic exposure
to chlordane may cause jaundice in humans. Chlordane may
also cause blood diseases including aplastic anemia and
acute leukemia in rats [20].
- Fate in humans and animals: Chlordane is
absorbed into the body through the lungs, stomach, and
skin. It is stored in fatty tissues as well as in the
kidneys, muscles, liver, and brain [2,20]. Chlordane has
been found in human fat samples at concentrations of 0.03
to 0.4 mg/kg in U.S. residents [20]. Chlorinated
hydrocarbons stored in fatty tissues can become released
into circulation if these fatty tissues are metabolized,
as in starvation or intense activity [2]. Chlordane that
is not stored in the body is excreted through the urine
and feces. Chlordane has been found in human breast milk
[25]. Rats that breathed chlordane vapor for 30 minutes
retained 77% of the total amount inhaled. Rabbits that
received 4 doses of chlordane stored it in fatty tissues,
the brain, kidneys, liver, and muscles [2]. Excretion of
orally administered chlordane is slow and can take days
to weeks. The biological half-life of chlordane in the
blood serum of a 4-year-old child who drank an
emulsifiable concentrate of chlordane was 88 days. In
another accidental poisoning of a 20-month-old child, the
half-life was 21 days [20,25].
Ecological Effects:
- Effects on birds: Chlordane is
moderately to slightly toxic to birds. The LD50 in
bobwhite quail is 83 mg/kg. The 8-day dietary LC50 for
chlordane is 858 ppm in mallard ducks, 331 ppm in
bobwhite quail, and 430 ppm in pheasant [9,26].
- Effects on aquatic organisms: Chlordane
is very highly toxic to fresh water invertebrates and
fish. The LC50 (96-hour) for chlordane in bluegill is
0.057 to 0.075 mg/L and 0.042 to 0.090 mg/L in rainbow
trout [9,17,26]. Chlordane bioaccumulates in bacteria and
in marine and freshwater fish species [17]. Expected
bioaccumulation factors for chlordane are in excess of
3000 times background water concentrations indicating
that bioconcentration is significant for this compound.
- Effects on other organisms: Chlordane is
highly toxic to bees and earthworms [26]. Studies done in
the late 1970s showed that the fatty tissues of land and
water wildlife contained large amounts of cyclodiene
insecticides, including chlordane [20].
Environmental Fate:
- Breakdown in soil and groundwater:
Chlordane is highly persistent in soils with a half-life
of about 4 years. Several studies have found chlordane
residues in excess of 10% of the initially applied amount
10 years or more after application [20]. Sunlight may
break down a small amount of the chlordane exposed to
light [9]. Evaporation is the major route of removal from
soils [20]. Chlordane does not chemically degrade and is
not subject to biodegradation in soils. Despite its
persistence, chlordane has a low potential for
groundwater contamination because it is both insoluble in
water and rapidly binds to soil particles making it
highly immobile within the soil [14]. Chlordane molecules
usually remain adsorbed to clay particles or to soil
organic matter in the top soil layers and slowly
volatilize into the atmosphere [14,20]. However, very low
levels of chlordane (0.01 to 0.001 ug/L) have been
detected in both ground and surface waters in areas where
chlordane was heavily used [21,25]. Sandy soils allow the
passage of chlordane to groundwater.
- Breakdown in water: Chlordane does not
degrade rapidly in water. It can exit aquatic systems by
adsorbing to sediments or by volatilization. The
volatilization half-life for chlordane in lakes and ponds
is estimated to be less than 10 days [20]. Chlordane has
been detected in surface water, groundwater, suspended
solids, sediments, bottom detritus, drinking water,
sewage sludge, and urban run-off, but not in rain water.
Concentrations detected in surface water have been very
low, while those found in suspended solids and sediments
are always higher (<0.03 to 580 ug/L). The presence of
chlordane in drinking water has almost always been
associated with an accident rather than with normal use
[20].
- Breakdown in vegetation: No data are
currently available.
Physical Properties:
- Appearance: Technical chlordane is
actually a mixture of at least 23 different components,
including chlordane isomers, other chlorinated
hydrocarbons, and by-products. It is a viscous, colorless
or amber-colored liquid with a chlorine-like odor [9].
- Chemical Name:
1,2,4,5,6,7,8,8-octachloro-2,3,3a,4,7,7a-hexahydro-4,7-methanoindene
[9]
- CAS Number: 57-74-9
- Molecular Weight: 409.83
- Water Solubility: 0.1 mg/L @ 25 C [9]
- Solubility in Other Solvents: s. in most
organic solvents, including petroleum oils [9]
- Melting Point: 104-107 C [9]
- Vapor Pressure: 1.3 mPa @ 25 C [9]
- Partition Coefficient: 2.78 [17]
- Adsorption Coefficient: 20,000 [14]
Exposure Guidelines:
- ADI: 0.0005 mg/kg/day [27]
- MCL: 0.002 mg/L [8]
- RfD: 0.00006 mg/kg/day [8]
- PEL: 0.5 mg/m3 (8-hour) [8]
- HA: Not Available
- TLV: Not Available
Basic Manufacturer:
Velsicol Chemical Corporation
10400 W. Higgins Rd.
Rosemont, IL 60018-5119
- Phone: 708-298-9000
- Emergency: Not Available
References:
References for the information in this PIP can be found in
Reference List Number 6
DISCLAIMER: The
information in this profile does not in any way replace or
supersede the information on the pesticide product labeling or
other regulatory requirements. Please refer to the pesticide
product labeling.