Environmental Medicine Integrating a Missing Element into Medical Education (1995) / Chapter Skim
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Case Study 9: Chlordane Toxicity
Case Study 9: Chlordane Toxicity
Pages 267-288
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From page 267... ...
Its residues are lipophilic and can remain in body fat stores for months. This monograph is one in a series of self-instructional publications designed to increase the primary care provider's knowledge of hazardous substances in the environment and to aid in the evaluation of potentially exposed patients.
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From page 268... ...
They both have had transient nasal congestion and severe headaches that lasted 2 to 3 hours, sometimes accompanied by lightheadedness. These symptoms are especially noticeable after they work in their basement workshop.
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From page 269... ...
of air. I mproper treatment includes pouring the chemical at the foundation line, carelessly injecting liquid chlordane directly into living spaces or air ducts, or spraying excessively in crawl spaces.
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From page 270... ...
Contaminated fish and other foods are assumed to account for 90% of the body burdens in the populations of Nordic countries where chlordane use was minimal. Certain crops, especially corn, can absorb chlordane from previously treated soil.
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From page 271... ...
Chlordane has been found at 166 of 1300 hazardous waste sites on the EPA National Priorities List. When chlordane was available commercially, most cases of systemic chlordane toxicity occurred after acute dermal exposure or accidental or suicidal ingestion.
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From page 272... ...
Chlordane and its metabolites are preferentially stored in adipose tissues, and concentrations increase as exposure duration increases. Oxychlordane is the major metabolite in most species and can account for up to 90% of the chlordane residues in adipose tissue.
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From page 273... ...
The solvent itself could produce adverse health effects. Because of experimental animal data, EPA considers chlordane a probable human carcinogen.
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From page 274... ...
O Gastrointestinal effects may result aver chlordane exposure by any route. O Because of experimental animal data, EPA considers chlordane a probable human carcinogen.
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From page 275... ...
C/inica/ Eva/uation History and Physical Examination O Patients who are chronically exposed to chlordane may develop a variety of nonspecific complaints. O Environmentally exposed patients often undergo considerable diagnostic testing before a connection is made with a possible toxic exposure.
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From page 276... ...
Hepatomegaly may also develop in chronically exposed persons. Although evidence linking blood dyscrasias with chlorinated compounds is inconclusive, persons with aplastic anemia or leukemia should have their environmental and occupational histories explored thoroughly for chronic exposure to chlordane (or other organochlorine compounds)
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From page 277... ...
However, because there is no known relationship between chlordane levels in the body and adverse health effects, measuring chlordane levels in biologic samples is generally not helpful in managing symptomatic chlordane poisoning. Testing for chlordane in biologic samples is usually reserved for research.
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From page 278... ...
However, clinical experience with this treatment modality is limited, and its effectiveness in chlordane poisoning is unproven. _ O Seizure control and maintenance of adequate respiration and oxygenation are primary concerns in the treatment of acute chlordane poisoning.
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From page 279... ...
Stanc/arc/s anc/ Regu/ations On March 6, 1978, registrations for all uses of chlordane on food crops were cancelled. Chlordane use on nonedible plants and its continued use for subterranean termite control were phased out over the following 5 years.
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From page 280... ...
Water To protect human health from the potential carcinogenic effects of chlordane through the ingestion of contaminated water and aquatic organisms, EPA regulates the level of chlordane in drinking water and has established guidelines to keep other water supplies safe. The enforceable maximum contaminant level (MCL)
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From page 281... ...
WHO Drinking water 0.3 ppb Advisory FDA Food Residual chlordane: in food crops 0.1 ppm Regulation in fish 0.3 ppm Regulation in animal fat 0.3 ppm Regulation (rendered) ^ACGIH = American Conference of Governmental Industrial Hygienists; EPA = Environmental Protection Agency; FDA = Food and Drug Administration; NAS = National Academy of Sciences; NIOSH = National Institute for Occupational Safety and Health; 0SHA = Occupational Safety and Health Administration; WHO = World Health Organization tTLV-TWA (threshold limit value~time-weighted average)
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From page 282... ...
Indoor air levels of chlordane and heptachlor following termiticide applications. Bull Environ Contam Toxicol 1987;39:91 1-8.
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From page 283... ...
Subacute chlordane poisoning. J Toxicol Clin Toxicol 1985;22:565-71.
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From page 284... ...
(4) The risk of developing cancer from chronic chlordane exposure is presently undefined, although EPA considers chlordane a potential human carcinogen on the basis of experimental animal data.
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From page 285... ...
(8) Cholestyramine has been shown to increase the fecal excretion of absorbed chlordane; however, clinical experience with this treatment modality is minimal, and its efficacy is unproven in treating chlordane-exposed patients.
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From page 286... ...
Chlordane vapors tend to persist inside a house. Indoor air monitoring studies conducted in homes treated properly with termiticides indicate that approximately 90% of the homes treated with chlordane have detectable levels of chlordane in the air 1 year after treatment.
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From page 287... ...
If improper application of chlordane is suspected, the suggestions above should be followed to improve the indoor airquality. In addition, the air in the home should tee tested.
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From page 288... ...
For homes that were treated properly, modifications are probably not worth the high expense. Modifications must be designed on a case-by-case basis, but may include replacing or relocating air ducts, replacing furnaces or ventilation systems with air exchangers, using barrier coatings of polyvinylidene chloride (e.g., Saranex)
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