Environmental exposure leads to a quarter of all disease

Published: 07/12/2006 - Updated: 10/27/2018

More than 24% of the global burden of disease is due to exposure to avoidable risks. A report by the World Health Organization (WHO) published shows that many of these environmental hazards can be prevented through well-targeted interventions. The report also estimated that over 33% of all illnesses among children under five years is due to exposure to environmental hazards. The prevention of these risks each year could save the lives of many people, including four million children, mainly in developing countries.

The report on health and environmental risks

The report, Preventing disease through healthy environments – towards an estimate of the environmental burden of disease is the most comprehensive and systematic study to date on a wide variety of diseases and injuries caused by preventable environmental hazards. The analysis, which focuses on environmental causes of disease and the influence of environmental factors in various diseases, provides new knowledge about the interrelationship between environment and health. It includes realistic estimates of the number of deaths and cases of illness and disability could be prevented each year by improving environmental management.

"The report issued today is an important contribution to the work being undertaken to better define the relationships between environment and health," said Dr. Anders Nordström, Director General of WHO. "We knew that the environment influences health a lot, but never had estimates as accurate as these, which will help us to demonstrate that investments aimed at creating a sound enabling environment can be an effective strategy for improving health and achieving sustainable development."

Report estimates that each year there are more than 13 million deaths caused by preventable environmental causes. Almost one third of the burden of mortality and morbidity in less developed regions is due to environmental causes. Over 40% of deaths from malaria and an estimated 94% of deaths from diarrheal disease – two leading causes of infant mortality – could be prevented by improving environmental management.

The four diseases most influenced by poor environmental conditions

The four diseases that affect more poor environmental conditions are diarrhea, infections, respiratory infections, various forms of unintentional injuries and malaria. Among the measures to be taken now to reduce this burden of disease due to environmental risks include those designed to promote safe household water storage and the adoption of appropriate hygiene practices, use of cleaner and safer fuels, the increasing the safety of buildings, the most prudent use and management of toxic substances at home and at work, and better water management.

"This report indicates for the first time how and to extent environmental risks affect different diseases and injuries," said Dr Maria Neira, Director of Public Health and the Environment of WHO. "It also shows very clearly the potential benefits of various investments, simple and coordinated public health and the environment in general. We call on ministries of health and environment, and other partners, to work for these environmental and public health is realized."

In this research, based on a systematic review of relevant publications, as well as in surveys conducted over 100 experts worldwide, it identifies specific diseases caused by known environmental hazards, and indicates the degree influence of these factors. "It brings together the best data available at present on the relationship between environmental hazards and health, for 85 categories of disease and trauma. Since the research focuses strictly on environmental hazards that can be modified, we can also see in which cases the combination of preventive health measures through better environmental management, including decontamination, can give better results. In fact, we now have a 'target list' which contains the problems we must deal to help health and environment, "said Dr. Neira.

Diseases that represent the largest annual health burden due to environmental factors in terms of deaths, illnesses and disabilities or life years adjusted for disability (DALYs) are:

  • Diarrhea (58 million DALYs per year; 94% of the burden of diarrheal disease), caused largely by unsafe water and sanitation, and lack hygiene.
  • The lower respiratory tract infections (37 million DALYs per year; 41% of reported cases globally), largely caused by air pollution in both external and internal spaces.
  • Unintentional injuries other than those caused by traffic (21 million DALYs per year; 44% of cases worldwide), including a wide variety of industrial accidents in the workplace.
  • Malaria (19 million DALYs per year; 42% of cases globally), largely caused by deficiencies in water supply, housing and management of land use that prevent effectively reduce vector populations.
  • The road traffic injuries (15 million DALYs per year, 40% of cases globally), largely as a result of deficiencies in urban planning or in environmental management of transport systems.
  • The chronic obstructive pulmonary disease – a slight increase in disease that is characterized by gradual loss of lung function (12 million DALYs per year; 42% of cases registered world) – caused largely by exposure to dusts and fumes in the workplace and other forms of air pollution in indoor and outdoor spaces.
  • Perinatal (11 million DALYs per year; 11 % of cases worldwide).

Most of these diseases due to exposure to environmental hazards are also the main cause of deaths, although there are some differences in the degree of lethality. All diseases that cause the largest absolute number of deaths per year due to preventable environmental hazards are associated with factors that can change through technologies, policies and preventive measures and public health services already available. Below we show the number of annual deaths caused by these diseases:

  • 2.6 million deaths annually from cardiovascular diseases
  • 1.7 million deaths annually from diarrheal diseases
  • 1.5 million deaths annually from lower respiratory infections
  • 1.4 million deaths annually from cancers
  • 1.3 million deaths annually from chronic obstructive pneumopathy
  • 470 000 annual deaths from road traffic accidents
  • 400 000 deaths annually from unintentional injuries

The report shows that in one way or another, the environment significantly affects more than 80% of cases of these serious diseases. Moreover, it was quantified only modifiable environmental risk, i.e. those that can quickly transform policies and technologies already available. The report also determines how far you can prevent the disease burden related to the environment.

If we act with determination and setting priorities for action to reduce the incidence of deadly diseases, millions of unnecessary deaths can be avoided every year. It is essential to work with sectors such as energy, transport, agriculture, and industry to embrace environmental causes profound.

DALYs = life years adjusted for disability: the number of years a person could live, lost by his untimely death, and years of productive life lost due to disability.

Source: World Health Organization

About the author
  • Jorgelina Reyente

    Expert in healthy cooking recipes and healthy lifestyle habits. She has a degree in communication sciences from the University of Buenos Aires.  She has completed postgraduate training in social sciences at the Sorbonne Nouvelle University - Paris III, France.

1 Reply to “Environmental exposure leads to a quarter of all disease”
  • Stacy says:

    I totally believe this, and I have suspected so for quite some time acutally. I am really quite saddened to see how much information we have available regarding disease preventiong (diet, exercise, mental health), and yet an alarming amount of the world continues to live out incredibly toxic lives regardless.