An effective environmental health plan will have a number of defining features which in themselves define environmental health for that plan, irrespective of the model chosen for the plan. Those defining features can be applied to each action topic within the plan.
There is not a single definition for what constitutes environmental health in common use. National and international authorities who are involved with environmental health issues often wish to adopt a definition which is compatible with their own national or other international legislation or which fits well with their own other plans relating to environment, health or aspects of environmental health. For these reasons the development of evironmental health action plans, with their own individual introductory definitions of environmental health, constitute the central work at this time defining what constitutes environmental health.
The scope of environmental health is so broad that a structured breakdown into manageable topics will be necessary. The Environmental Health Action Plan for Europe provides a breakdown with four broad categories: environmental health management tools; specific environmental hazards; living and working environments; and economic sectors. The breakdown into specific environmental hazards is sometimes called a vertical categorisation in contrast with a horizontal categorisation by economic sectors. The two breakdowns each have their own uses, advantages and disadvantages, and are likely to appeal to different interests. This is likely to be true for any other way of splitting environmental health into manageable topics.
The priority environment and health issues identified at the Second European Conference on Environment and Health in Helsinki in June 1994 include food and water safety, ambient and indoor air quality, the risk of accidents, human settlements, occupational health and the consequences of armed hostilities. The Declaration on Action for Environment and Health in Europe, endorsed by ministers in Helsinki, outlined these priority areas further; contaminated food and water; ambient and indoor air pollution; urban health; ecology and health; the consequences of armed hostilities; occupational health; and death and injuries from all forms of accident, including nuclear emergencies.