Environmental Medicine Integrating a Missing Element into Medical Education (1995) / Chapter Skim
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Case Study 44: 1,1,1-Trichloroethane
Case Study 44: 1,1,1-Trichloroethane
Pages 750-766
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From page 750... ...
~ Inhalation abuse of 1,1,1-trichloroethane can result in "sudden sniffing death. " 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 751... ...
The environmental specialist searches the Toxic Chemical Release Inventory (TRI) database and informs you that the plant in question is a major emitter of 1,1,1trichloroethane (TCA)
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From page 752... ...
Some of these items include the following: fabric water repellents, spot removers, spray shoe polishes, spray paints, paint thinners and removers, pesticides, lubricants for auto door locks, tape and video recorder head cleaners, electric shaver cleaners, and typewriter correction fluids. Some correction fluids and thinners that have high concentrations of TCA are widely abused through inhalation for their narcotic effects.
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From page 753... ...
Due to the large input of TCA into the atmosphere and its slow degradation, the amount of TCA in ambient air is increasing by 12% to 17% annually. TCA slowly diffuses to the stratosphere where photodegradation is rapid, and the chlorine free radicals that are generated contribute to the destruction of the ozone layer.
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From page 754... ...
Intentional inhalation of TCA for its narcotic effects is a problem, however, and is most common among adolescents. Persons who deliberately sniff glue or solvents to achieve euphoria risk adverse health effects, such as "sudden sniffing death" from cardiac dysrhythmias.
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From page 755... ...
It has a half-life for elimination from the blood of approximately 53 hours; small amounts of TCA have been detected in the breath several days after exposure has ceased. The remaining 10% of an inhaled dose is excreted unchanged in the urine or metabolized by hepatic cytochrome P-450 mixed-function oxidase enzymes to 1richloroethanol and then to trichloroacetic acid.
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From page 756... ...
TCA contact with unprotected eyes can produce transient and superficial tissue effects, including chemosis, hyperemia, and conjunctivitis. Neurologic Effects With increasing concentration of TCA, CNS depression and euphoric narcosis occur in proportion to the amount of TCA absorbed.
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From page 757... ...
A multigeneration reproductive study of rats exposed to TCA in drinking water found no reproductive effects. Only one inhalation study found evidence of minor embryotoxicity in experimental animals.
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From page 758... ...
A regional poison control center can help determine ingredients of brand name products and treatment for patients who have been exposed.
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From page 759... ...
Chronic exposure to levels greater than 350 ppm may result in mild headaches, short-term memory loss, sleep disturbances, and ataxia. The patient should be questioned about other exposures that could be contributory including alcohol and drug abuse, prescription drugs, and psychiatric disorders, as well as exposure to other chemical neurotoxlns.
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From page 760... ...
Trichloroacetic acid binds to serum albumin and will persist in the blood with a half-l~fe of about 3 days. These metabolizes can be detected in the urine for a few days after mild exposures and a few weeks after heavy exposures.
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From page 761... ...
Hepatic and renal function should be assessed. If the exposure was occupational, periodic workplace air monitoring should be carried out to ensure compliance with regulations of the Occupational Safety and Health Administration (OSHA)
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From page 762... ...
For trichloroethanol, the BEI is 30 milligrams/liter (mg/L) in urine samples obtained at the end of the workweek, and for trichloroacetic acid, the BEI is 10 mg/L.
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From page 763... ...
* Under review Drinking water 200 ppb Regulation Ambient water 18 ppm Regulation ^ACGIH = American Conference of Governmental Industrial Hygienists; EPA = Environmental Protection Agency; NIOSH = National Institute for Occupational Safety and Health; 0SHA = Occupational Safety and Health Administration tTLV-lWA (threshold limit value time-weighted average)
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From page 764... ...
1,1,1-Trichloroethane exposure, biologic monitoring by breath and urine analyses. Int Arch Occup Environ Health 1982; 49:293-304.
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From page 765... ...
Chronic, low-level TCA exposure produces primarily necrologic effects including agitation, lethargy, decreased memory, and sleep disturbances. Chronic abuse of TCA may cause cardiac dysrhythmias and central nervous system depression leading to respiratory arrest.
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From page 766... ...
Inhalation abuse of solvents is most common in adolescents, and many states have mandated restrictions on selling spray paints and solvents to juveniles.
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