The Centers for Disease Control program to prevent primary and secondary disabilities in the United States.

The Disabilities Prevention Program builds on traditional Centers for Disease Control (CDC) strengths in public health surveillance, epidemiology, and technology transfer to State and local governments in translating the findings of research into prevention programs. The objectives of the CDC program are to provide a national focus for the prevention of primary and secondary disabilities, build capacity at the State and community levels to maintain programs to prevent disabilities, and increase the knowledge base necessary for developing and evaluating effective preventive interventions. During 1989, CDC, in consultation with the National Council on Disabilities and members of the disability community, has elected to focus its effort in three areas: developmental disabilities, injuries to the head and spinal cord, and secondary complications among persons with physical disabilities.

The risk of risk assessment.

Appropriate risk management can only be based on sound risk assessment. The sources of uncertainty involved in risk assessment are discussed and a number of approaches to improving such assessments are recommended.

2,3,7,8-Tetrachlorodibenzo-p-dioxin levels in adipose tissue of exposed and control persons in Missouri. An interim report.

The compound 2,3,7,8-tetrachlorodibenzo-p-dioxin, commonly known as dioxin, was measured in the adipose tissue of 39 persons with a history of residential, recreational, or occupational exposure in Missouri and in 57 persons in a control group. All participants had detectable levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin in their adipose tissue, but the exposed group had significantly higher levels. Levels of six of the exposed persons were more than five times greater than the level of the highest control. Measuring 2,3,7,8-tetrachlorodibenzo-p-dioxin in adipose tissue provides a much improved index of exposure, an important advance for research studies evaluating the possible health effects of this compound.

Trichloroethylene: an update.

The toxicity of tricholoroethylene (TCE) has been summarized in a number of reviews. In this particular update, only the more recent studies that deal with metabolism and carcinogenicity have been examined. In reviewing the more recent publications on metabolism of TCE, we determined that differences exist in its metabolism if low doses are compared with high doses in animals. There may also be a difference in the metabolism of TCE between different species--namely mice, rats, and humans. TCE has not been shown to be a potent carcinogen in rats and it only seems to be a potent carcinogen in one specific strain of mice, namely the B6C3F1 mouse. Epidemiology studies have been rather limited. The number of persons examined so far for chronic toxic effects is small, compared with the enormous size of the work force that is exposed to TCE over prolonged periods. On an empirical basis, the occupational experience with TCE does not suggest that this compound is a potent carcinogen. The risk associated with exposure to trace amount (ppb) concentrations of TCE in water appear to be minimal or perhaps negligible. Because there are differences in metabolism of TCE, it is important that theoretical risks attributed to TCE in the past be reexamined. It is highly possible that in humans, the metabolic pathway leading to the formation of the proximate carcinogen is not activated at low doses, where TCE is excreted by first-order kinetics.