It would not be unusual for the computer chip manufacturing plant to store TCA in underground storage tanks. Leaking storage tanks at electronics plants have been reported to contaminate groundwater in several areas. Testing the community’s water supply could help to determine whether leaking underground tanks are contributing to TCA exposure.
You tell the reporter that he should not run the story and falsely alarm parents. You then attempt to put the information in perspective for the media representative. Under EPA rules, drinking water may contain up to 200 µg/L (200 ppb); bathing water may contain up to 18,000 ppb. You are not aware of a TCA standard for disposable diapers. While it is true that children are more susceptible to many toxicants and often exhibit signs of poisoning at lower levels than adults (e.g., lead or organophosphate pesticide exposures), the TCA level of 20 ppb is not cause for alarm. You further explain that TCA is one of the less hazardous solvents in terms of health effects. The level of TCA found is also not likely to cause diaper rashes, which occur in more than 20% of infants in the first 6 months of life.
The best test for confirmation of exposure is the measurement of TCA in the blood. If TCA is detected in the blood, the adolescent most likely inhaled it within the last 5 to 7 days. If TCA metabolites (trichloroethanol or trichloroacetic acid) are also detected in the same blood sample, he may be a chronic abuser. TCA is quickly exhaled from the lungs; therefore, TCA metabolites are not likely to be present after a one-time use.
An approach that requires biologic testing is a bit adversarial, however. Rather, both parents should educate their son about the hazards of inhalant abuse. They should get involved in closely monitoring their child’s activities. If school performance is deteriorating or they have other reasons to suspect their son’s activities, enrolling him in a community substance abuse program and enlisting the help of a mental health professional to explore why their son is taking such risks may be appropriate. Inhalation abuse of solvents is most common in adolescents, and many states have mandated restrictions on selling spray paints and solvents to juveniles.
TCA exposure has not been associated with multiple sclerosis (MS). MS is the most common chronic disease of the central nervous system in young adults in North America. It is characterized by the occurrence of discrete areas of demyelination or plaques in the brain or spinal cord with symptoms including some degree of paralysis, nystagmus, and disturbances of speech, depending on the site of the lesions.
Although degreasing or defatting skin of endogenous oils is the most common skin problem with TCA, contact dermatitis, hives, and urticaria have been reported, usually associated with a history of these conditions. These allergic conditions are associated with use of TCA in a stabilized form, which contains dioxane or epichlorohydrin. Both of these stabilizers are not only stronger irritants than TCA, but also skin sensitizers. (See Case Studies in Environmental Medicine: Skin Lesions and Environmental Exposures.)
The appearance of symptoms will depend upon dose, duration, and route of exposure. The routes of exposure include ingestion of the contaminated water and inhalation and dermal exposure during showering, laundering, or cleaning. The highest level found is not significantly above the EPA regulation. The mean daily intake of TCA from all sources (air, food, and water) has been determined to be between 50 and 1000 µg/day; therefore, one would not expect symptoms in most people. Because children and elderly persons are generally more susceptible to toxic agents, households with these occupants could consider changing their source of water.