The definition of environmental health varies from organization to organization, although the basic premise remains the same. Below are definitions from various federal and nonfederal organizations/agencies.
Environmental health addresses all the physical, chemical, and biological factors external to a person, and all the related factors impacting behaviors. It encompasses the assessment and control of those environmental factors that can potentially affect health. It is targeted towards preventing disease and creating health-supportive environments. This definition excludes behavior not related to environment, as well as behavior related to the social and cultural environment, and genetics. – World Health Organization
Environmental health and protection refers to protection against environmental factors that may adversely impact human health or the ecological balances essential to long-term human health and environmental quality, whether in the natural or man-made environment. – National Environmental Health Association
Environmental Health is the field of science that studies how the environment influences human health and disease. “Environment,” in this context, means things in the natural environment like air, water and soil, and also all the physical, chemical, biological and social features of our surroundings.
The man-made, or “built,” environment includes physical structures where people live and work such as homes, offices, schools, farms and factories, as well as community systems such as roads and transportation systems, land use practices and waste management. Consequences of human alteration to the natural environment, such as air pollution, are also parts of the man-made environment.
The social environment encompasses lifestyle factors like diet and exercise, socioeconomic status, and other societal influences that may affect health. – National Institute of Environmental Health Science