Environmental burden of disease

Environmental hazards such as air pollutants, noise and chemicals can cause illness, disability or even death. The results of international studies on the environmental burden of disease vary widely in different countries, with estimates ranging from about 2 to 20% of the total disease burden caused by environmental exposures (ENHIS). These differences are mainly due to differences in methodology (e.g. which risk factors are included) and partly related to actual differences in environmental conditions.

In 2006, the World Health Organisation (WHO) estimated that in the WHO European Region as much as 14-19% of disease is caused by environmental exposures that can be averted (WHO, 2006d).

It is important to recognise that these percentages refer to a selected set of the currently known environmental risk factors for which quantification of health impacts is possible. In addition, disease burden calculations are a simplification of a very complex reality consisting of combined exposures to different risk factors by different pathways.

Children's burden of disease

Environmental exposures are known to be important contributors to the global burden of disease among children and adolescents, but there are still gaps in our knowledge about the magnitude and regional distribution of the environmental burden. Child-specific data are only available for specific environmental factors.

Children have a special vulnerability to environmental pollution, because their body is still developing. Furthermore, their specific exposure patterns make them subject to higher exposures.

WHO calculated the impact of the environment on child health in the European Region. The results show that indoor and outdoor air pollution, unsafe water conditions, lead exposure and injuries are important risk factors in 0-19 year old children (WHO, 2004f). The report further estimates that more than 24% of deaths and 22% of disease in children under the age of 14 is caused by environmental exposures. Well-targeted interventions can prevent much of this environmental risk and save thousand lives a year.

Gastrointestinal diseases

Gastrointestinal infection (infectious intestinal disease) comprises a variety of communicable diseases, which gain entry by and/or affect the gastrointestinal tract. Environmental factors such as drinking and bathing water pollution or food contamination are among major determinants.

In the European Region the mortality of diarrhoeal disease attributable to poor water quality, sanitation and hygiene in children aged 0–14 years is estimated at 13 548 (5.3% of all deaths) (WHO, 2004f).

Cardiovascular diseases

Cardiovascular diseases (CVDs) are the main cause of illness and premature death in the world, almost equally in men and women. The causes of CVDs are well established and well known. The most important include unhealthy diet, physical inactivity and tobacco use. Outdoor and indoor air pollution are among the environmental determinants of CVDs. Addressing these risk factors would provide a great potential for prevention.

Respiratory diseases

Respiratory diseases of concern include chronic respiratory diseases, such as asthma, chronic obstructive pulmonary disease (COPD) and lung cancer, as well as acute respiratory infections. Tobacco smoke is the principal risk factor for these diseases. Other risk factors include heavy exposure to air pollution (from indoor and outdoor sources) and occupation-related exposure.

It is estimated that exposure to tobacco smoke increases the number of asthma episodes in children aged under 14 years by 6 to 10%, depending on the current smoking prevalence in each country (WHO, 2007). For air pollution, WHO estimated that throughout the Region around 700 deaths annually from acute respiratory infections in children aged 0–4 years can be attributed to PM10 exposure (WHO, 2007b).

Cancers

Cancer remains one of the biggest causes of death in Europe. 40% of cancer can be prevented. Tobacco use is the single largest preventable cause of cancer in the world. Environmental hazards such as air, water and food contamination, radiation and occupational exposures are also among the causes of cancer.

The overall estimate of lung cancer that can be attributed to radon is approximately 9% for Europe with attributable risk estimates ranging from about 3% of lung cancer deaths in the Netherlands or the United Kingdom to 21% in the Czech Republic (WHO, 2007q).

Overweight and obesity

Excess body weight and obesity in children and young people are on the rise in Europe. Inadequate nutrition and lack of physical activity are important risk factors. A high body mass index (BMI) in adolescence predicts elevated adult mortality and cardiovascular disease rates, even if the excess body weight is lost.

Physical activity levels in children and adolescents are low and decline with age: 11-year-olds are more physically active than 13- and 15-year-olds. Across all the countries in the Health Behaviour in School-aged Children study, about one third of all children (39%) report taking physical activity at a level that meets the current guidelines (WHO, 2007c, see also EUphact overweight).

Injuries

In the WHO European region, the three leading causes of death from unintentional injuries in the age group 0-19 years are road traffic injuries (37%), drowning (15%) and poisonings (8%) (ENHIS).

For road traffic injuries, up to 6400 deaths per year are estimated to occur among children aged 0-14 years and up to 25 500 among young people aged 15-24 years. Some countries show relatively low mortality rates, which indicates that deaths from road traffic injuries are preventable (WHO, 2007d).

Developmental disorders

The central nervous system is particularly vulnerable to toxic effects during early development. Nervous system damage, once incurred during a developmental stage, is likely to be irreversible and may change the affected individual’s quality of life and economic and social success. The extent to which current environmental pollution causes adverse effects on brain development is unknown. The contaminants that have been studied in the greatest detail, such as lead, methylmercury and polychlorinated biphenyls (PCBs), are likely to cause adverse health effects in subgroups of European populations with increased exposures.