Report on the Environment
Other Human Exposure and Health Topics
What You Can Do
What are the trends in health status in the U.S.?
An overarching goal of public health agencies is to increase quality and years of healthy life and to eliminate health disparities. Tracking historical trends in general health status can help identify where interventions have improved the health of a population or where interventions may be needed (e.g., exploring causative factors and preventive measures). For example, a key concern for EPA is what possible environmental exposures could be contributing to the diseases or conditions that are the leading causes of death in the U.S.
The topics covered under this question are broad and not intended to represent specific diseases or conditions related to the environment. Environmental contaminants from air, water, and land can influence the overall health of a nation. As described in the "Human Health Chapter Introduction", however, many factors other than the environment influence the health of a population, such as socio-demographic attributes, behavioral and genetic risk factors, level of preventive care, and quality of and access to health care. Though no consensus exists on the relative contribution of environmental exposures, tracking overall health in the U.S. provides important context for the next section of this chapter, which examines specific acute and chronic diseases and conditions that may be linked more specifically with exposures to environmental contaminants.
As defined by the World Health Organization, health is a state of complete physical, mental, and social well-being, and not the mere absence of disease or infirmity.16 The health status of a population can be measured by a wide range of factors: birth and death rates, life expectancy, quality of life, morbidity from specific diseases, risk factors, use of ambulatory care and inpatient care, accessibility of health personnel and facilities, financing of health care, health insurance coverage, and many other factors.17
While no single set of measures can completely characterize the health of a large and diverse population, CDC and other health agencies worldwide consistently have viewed life expectancy and mortality data as indicators of overall population health because they represent the cumulative effects of social and physical environmental factors, behavioral and genetic risk factors, and the level and quality of health care. These data include the leading causes of mortality (among both infants and the general population), which provide a broad perspective on the diseases and conditions that are having the greatest impact on the nation’s health. Infant mortality is a particularly useful measure of health status, because it indicates both the current health status of the population and predicts the health of the next generation.18 It reflects the overall state of maternal health as well as the quality and accessibility of primary health care available to pregnant women and infants.
Tracking health status using such indicators provides information on changing or emerging trends. At the beginning of the 20th century, the population of the U.S. was characterized by a low standard of living, poor hygiene, and poor nutrition; communicable diseases and acute conditions were major causes of most premature deaths. Over the course of the century, public health measures such as improved sanitation and drinking water treatment led to a dramatic decrease in deaths due to infectious diseases and a marked increase in life expectancy. As the population has aged, chronic diseases such as heart disease and cancer have become the leading causes of death.19 These diseases may require a different approach to prevention, detection, and treatment compared to the infectious and acute illnesses more common in the past.