Archived: WMA Declaration of Sao Paulo on Pollution

Adopted by the 30th World Medical Assembly Sao Paulo, Brazil, October 1976
and revised by the 36th World Medical Assembly Singapore, October 1984
and rescinded at the WMA General Assembly, Santiago 2005


The World Medical Association, having considered the problem of pollution at its Scientific Conference held in Sao Paulo in 1976, emphasizes the importance of the ecological balance between people and their surroundings and stresses that as countries undergo social and economical development they should take steps for the improvement of the quality of their environment.

The problem of pollution affects not only the viability and beauty of the environment, but constitutes a growing threat to the very health of the humans who occupy it. Thus physicians must play a major role in prevention of disease due to pollution.


Environmental pollution may be defined as the result of actions taken by people, either consciously or due to neglect or ignorance, that degrade or contaminate the natural environment. For example, the indiscriminate disposal of chemical wastes may lead to irreparable contamination of precious acquifers from which come water that is essential to human life.

Certain adverse physical factors, ionizing radiation and chemicals such as chromium, asbestos, and those in tobacco are associated with cancer and other fatal or disabling illnesses, including birth and developmental defects among the descendants of exposed persons. Controlling exposures to such factors would have a salutary effect on people’s health and survival. Therefore, high priority should be given to the elimination of adverse physical factors in the home, school, workplace, and elsewhere.

Microbiological and chemical agents may prominently and adversely affect the health of workers and of the general population. Micro-biological agents can cause communicable diseases, as is apparent from decades of recorded experience. Chemicals can cause non-communicable hazards. Persons who are involved with food production and distribution have the responsibility of minimizing consumers’ exposures, not only to harmful microbiological agents, but also to agricultural chemicals used to increase crop production and to unsafe additives that may be used to preserve foods.

Component of Problem

Among the specific contributors to the problem of pollution, the following may be mentioned:

  • Air pollution involving oxides of nitrogen, photochemical oxidents, hydrocarbons, sulfur dioxide, lead, and certain particulates in the ambient air. Such substances can cause adverse pathophysiologic effects in children and adults and can damage plants and property.
  • Water pollution due to discharge of improperly treated human sewage wastes, and of agricultural and industrial wastes, into bodies of water. Such discharges contaminate drinking water with viruses, bacteria and other infectious micro-organisms; inorganic and organic chemicals, and radio-active substances. Water pollution also results in the reduction of recreational opportunities and of commercial fishing resources.
  • Solid wastes that attract rodents and insects at disposal sites and degrade the air and water; wastes can release toxic materials into the environment.
  • Excessive sound levels produced by industrial sources, transportation systems, audio systems and other means, may lead to permanent hearing loss, other pathophysiologic effects, and emotional disturbances.

Responsibility of Physicians

Physicians have the responsibility to educate the public and to encourage the establishing and maintaining of programs of environmental protection for their communities.


Individual physicians and National Medical Associations should take appropriate action to discharge the foregoing responsibility.

Air Pollution, Environmental Hazards, Water Pollution