WHO:Clean air for health: Difference between revisions

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:''This text is taken from the WHO report "Health and Environment in Europe: Progress Assessment", 2010, ISBN 978 92 890 4198 0. [http://www.euro.who.int/document/e93556.pdf]''
:''This text is taken from the WHO report "Health and Environment in Europe: Progress Assessment", 2010, ISBN 978 92 890 4198 0. [http://www.euro.who.int/document/e93556.pdf]''


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==Clean air and its public health significance – new insights==
==Clean air and its public health significance – new insights==


Knowledge about the links between health and air quality has significantly advanced in the last two decades. There is more evidence about the role of pollutants in the aetiology of respiratory diseases and new insights have been gained into the impacts of fine particulate matter on cardiovascular health. Hundreds of studies throughout the world confirm the association of mortality, or hospital admissions, with levels of the most common urban air pollutants. The results of this research combined with data on air quality in Europe, indicate that the pollution of air with fine particulate matter leads to a nine-month shortening of life expectancy in Europe. New studies among children have indicated that exposure not only increases the prevalence of respiratory symptoms, but also raises the incidence of new respiratory diseases. New studies also indicated that substantial gains in public health resulting from improvements in air quality, for example, the attribution of 15% of the overall increase in life expectancy to the reduction of fine particulate matter in the United States. This evidence has been reviewed and summarized by WHO in the updated ''Air quality guidelines'', and is being used to design new approaches and regulations to reduce the health risks of pollution.
Knowledge about the links between health and air quality has significantly advanced in the past two decades. There is more evidence about the role of pollutants in the aetiology of respiratory diseases and new insights have been gained into the impacts of fine particulate matter on cardiovascular health. Over hundreds of studies around the world confirm the association of mortality, or hospital admissions, with levels of the most common urban air pollutants. The results of this research combined with data on air quality in Europe, indicate that the pollution of air with fine particulate matter leads to a nine-month shortening of life expectancy in Europe. New studies among children have indicated that exposure not only increases the prevalence of respiratory symptoms, but also raises the incidence of new respiratory diseases. New studies also indicated that substantial gains in public health resulting from improvements in air quality, for example, the attribution of 15% of the overall increase in life expectancy to the reduction of fine particulate matter in the United States. This evidence has been reviewed and summarized by WHO in the updated ''Air quality guidelines'', and it is being used to design the new approaches and regulations to reduce the health risks of pollution.


New evidence is accumulating on the burden of disease due to indoor air pollution. The risks to health of exposure to second-hand tobacco smoke have been widely recognized and are reflected by widespread programmes to eliminate tobacco smoke from indoor spaces. Other hazardsthat are common in indoor air, such as biological contaminants arising from damp and mould, have been well characterized by the newly published ''WHO Guidelines for indoor air quality – dampness and mould''. An understanding of these links is an essential element of action to reduce the burden of disease and to benefit public health.
New evidence is accumulating on the burden of disease due to indoor air pollution. The risks to health of exposure to second-hand tobacco smoke have been widely recognized and are reflected by the widespread programmes to eliminate tobacco smoke from indoor spaces. Other hazardsthat are common in indoor air, such as biological contaminants arising from damp and mould, have been well characterized by the newly published ''WHO Guidelines for indoor air quality – dampness and mould''. An understanding of these links is an essential element of action to reduce the burden of disease and to benefit public health.


Considering this new research information, this section reviews the background patterns of diseases affected by common air pollutants, presents the distribution and trends in exposure in European populations, and characterizes the inherent risks and the opportunities for their reduction.<ref name="who"/>
Considering this new research information, this section reviews the background patterns of diseases affected by common air pollutants, presents the distribution and trends in exposure in European populations, and characterizes the inherent risks and the opportunities for their reduction.<ref name="who"/>
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[[file:deathraterespitory.png|thumb|250px|Average post-neonatal death rates from respiratory diseases (per 1000 live births)<ref name="who"/>]]
[[file:deathraterespitory.png|thumb|250px|Average post-neonatal death rates from respiratory diseases (per 1000 live births)<ref name="who"/>]]


A considerable variation could be observed across the Region, with a gradual increase in the death rate from west to east. The poorer economic and environmental situation in eastern Europe contributes to the higher rates seen in that part of the Region. Several countries have virtually eliminated respiratory diseases as a cause of post-neonatal death, indicating the huge potential for further reductions in other countries.
A considerable variation could be observed across the Region, with a gradual increase in the death rate from west to east. The poorer economic and environmental situation in eastern Europe contributes to higher rates seen in that part of the Region. Several countries have virtually eliminated respiratory diseases as a cause of post-neonatal death, indicating the huge potential for further reductions in other countries.


There are noticeable differences in the causes of respiratory infections between various regions of Europe. For instance, bacterial infections are more common in developing countries while viral infections cause most acute lower respiratory infections in developed countries. In temperate European countries, there is a marked seasonal variation in acute lower respiratory infections with a significant rise in incidence in winter months falling to relatively low levels in summer.
There are noticeable differences in the causes of respiratory infections between various regions of Europe. For instance, bacterial infections are more common in developing countries while viral infections cause most acute lower respiratory infections in developed countries. In temperate European countries, there is a marked seasonal variation in acute lower respiratory infections with a significant rise in incidence in winter months falling to relatively low levels in summer.
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Asthma continues to affect many individuals into adulthood, which indicates that the prevalence of asthma in adults is also high. However, not all chronic respiratory diseases start in childhood. Chronic lung diseases that cause limitations in lung airflow (often collectively referred to as chronic obstructive pulmonary disease) tend to begin in mid-life. Although mortality from these diseases is falling in the Region, it still causes 4% of all deaths and contributes to 5% of the overall burden of disease. Globally, their burden is increasing and, should current trends persist, they are projected to become the third leading cause of death by the year 2030. Currently, the most important risk factors for chronic obstructive pulmonary disease are tobacco-smoking, indoor and outdoor air pollution, and occupational exposure to dusts and chemicals.
Asthma continues to affect many individuals into adulthood, which indicates that the prevalence of asthma in adults is also high. However, not all chronic respiratory diseases start in childhood. Chronic lung diseases that cause limitations in lung airflow (often collectively referred to as chronic obstructive pulmonary disease) tend to begin in mid-life. Although mortality from these diseases is falling in the Region, it still causes 4% of all deaths and contributes to 5% of the overall burden of disease. Globally, their burden is increasing and, should current trends persist, they are projected to become the third leading cause of death by the year 2030. Currently, the most important risk factors for chronic obstructive pulmonary disease are tobacco-smoking, indoor and outdoor air pollution, and occupational exposure to dusts and chemicals.


It has only become fully apparent in the last decade that air pollution, especially of fine particulates, plays a major role in cardiovascular disease. Over half (52%) of deaths, and 23% of the overall burden of disease in the Region, arises from cardiovascular disease. Even a relatively small increases in the risk of cardiovascular disease will translate into huge absolute numbers of additional people suffering more severely from the disease.<ref name="who"/>
It has only become fully apparent in the last decade that air pollution, especially of fine particulates, plays a major role in cardiovascular disease. More than half (52%) of deaths, and 23% of the overall burden of disease in the Region, arises from cardiovascular disease. Even a relatively small increases in the risk of cardiovascular disease will translate into huge absolute numbers of additional people suffering more severely from the disease.<ref name="who"/>


==Outdoor air pollution and its impact on health in Europe==
==Outdoor air pollution and its impact on health in Europe==
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A number of outdoor air pollutants affect on health. The impacts of the two widespread pollutants evaluated here, particulate matter and ozone are the most known but other pollutants (volatile organic compounds, nitrogen oxide, sulfur oxide, etc.) should also be considered for policy action.
A number of outdoor air pollutants affect on health. The impacts of the two widespread pollutants evaluated here, particulate matter and ozone are the most known but other pollutants (volatile organic compounds, nitrogen oxide, sulfur oxide, etc.) should also be considered for policy action.


Large amounts of '''particulate matter''' (PM) are generated by various human activities. Since particles can travel hundreds and thousands of kilometres in the air and are partly created from gaseous pollutants in the atmosphere, their effects can be seen far from the source. PM consists of solid and liquid particles that vary in their physical and chemical properties and that are classified by particle diameter (in micrometres – μm). When inhaled, PM10 particles (with a diameter of less than 10 μm) penetrate deep into the respiratory system. Finer particles (with a diameter of less than 2.5 μm) then go on to penetrate the lungs and pass into the bloodstream and are carried into other body organs. Concerned that these particles cause a wide range of health impacts, WHO has developed guidelines addressing their risks.
Large amounts of '''particulate matter''' (PM) are generated by a number of activities by human beings. Since particles can travel hundreds and thousands of kilometres in the air and are partly created from gaseous pollutants in the atmosphere, their effects can be seen far from the source. PM consists of solid and liquid particles that vary in their physical and chemical properties and that are classified by particle diameter (in micrometres – μm). When inhaled, PM10 particles (with a diameter of less than 10 μm) penetrate deep into the respiratory system. Finer particles (with a diameter of less than 2.5 μm) then go on to penetrate the lungs and pass into the bloodstream and are carried into other body organs. Concerned that these particles cause a wide range of health impacts, WHO has developed guidelines addressing their risks.


Long-term average exposure to PM is associated with both the risks of chronic effects on children’s health, such as impaired development of lung function, and the frequency of acute effects, such as the aggravation of asthma or incidence of respiratory symptoms.Very young children, including unborn babies, are particularly sensitive to air pollutants. Exposure to PM is also associated with increased hospital admissions and mortality in adults. The risk increases linearly with the concentration of pollution, and there is no evidence to suggest a threshold for PM below which no adverse health effects would occur.
Long-term average exposure to PM is associated with both the risks of chronic effects on children’s health, such as impaired development of lung function, and the frequency of acute effects, such as the aggravation of asthma or incidence of respiratory symptoms.Young children, including unborn babies, are particularly sensitive to air pollutants. Exposure to PM is also associated with increased hospital admissions and mortality in adults. The risk increases linearly with the concentration of pollution, and there is no evidence to suggest a threshold for PM below which no adverse health effects would occur.


Data from year 2007 demonstrated that there are important disparities in P<sub>10</sub> exposure in the Region: average country levels varied from 16 μg/m3 (Finland and Ireland) to 45–52 μg/m3 (Bulgaria, Romania and Serbia) and 72 μg/m3 in Turkey. Within-country differences were also substantial. In total, over 92% of the urban population for which PM10 data are available live in cities where the WHO air quality guideline for PM<sub>10</sub> is exceeded.<ref name="who"/>
Data from year 2007 showed that there are important disparities in P<sub>10</sub> exposure in the Region: average country levels varied from 16 μg/m3 (Finland and Ireland) to 45–52 μg/m3 (Bulgaria, Romania and Serbia) and 72 μg/m3 in Turkey. Within-country differences were also substantial. In total, over 92% of the urban population for which PM10 data are available live in cities where the WHO air quality guideline for PM<sub>10</sub> is exceeded.<ref name="who"/>


[[file:emissionsectorseu27.png|thumb|250px|Contribution of key sectors to emission of PM in the EU27, 2007<ref name="who"/>
[[file:emissionsectorseu27.png|thumb|250px|Contribution of key sectors to emission of PM in the EU27, 2007<ref name="who"/>
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===Second-hand tobacco smoke===
===Second-hand tobacco smoke===


Children and adolescents (as well as adults) can be exposed to tobacco smoke indirectly through second-hand tobacco smoke (SHS), which is defined as the involuntary or passive breathing of air contaminated with tobacco smoke by someone who is not smoking. SHS is the dominant form of indoor air pollution in spaces where tobacco is smoked, even where areas are properly ventilated.
Children, adolescents and also adults can be exposed to tobacco smoke indirectly through second-hand tobacco smoke (SHS). SHS is defined as the involuntary or passive breathing of air which is contaminated with tobacco smoke by someone who is not smoking. It is a dominant form of indoor air pollution in spaces where tobacco is smoked and even where areas are properly ventilated.


Tobacco-smoking accounts for approximately 30% of all cancer deaths in the general population as well as for a substantial proportion of cardiovascular and respiratory disease. It is also well-established that exposure to SHS creates a huge burden to health. The most recent calculations indicate that more than 72 000 people in the EU25 alone die each year due to exposure to SHS in the home. In addition to exposure at home, workplace exposure to SHS is also linked to an increased risk of death. In the EU in 2008, 6000 deaths were attributable to SHS in offices, bars and restaurants, 40% of which were in non-smoking staff. These estimates do not include the health burden of customers. The burden of illness related to exposure to SHS in public places can be greatly reduced by smoking bans. A recent study analysing acute coronary events in Italy before and after the implementation of the smoking ban in January 2005 found a statistically significant reduction  in acute coronary events, amounting to as much as approximately 11% in people aged 35–64 years and approximately 8% in
Tobacco-smoking accounts for at least 30% of all cancer deaths in the general population as well as for a substantial proportion of cardiovascular and respiratory disease. It is well-established that exposure to SHS creates a huge burden to health. The most recent calculations have indicated that more than 72,000 people in the EU25 alone die each year due to exposure to SHS inside the home environment. Along with the exposure at home, workplace exposure to SHS is also linked to an increased risk of death. In 2008, in the EU, 6000 deaths were attributable to SHS in offices, bars and restaurants, 40% of which were in non-smoking staff. These estimates do not include the health burden of customers. The burden of illness related to exposure to SHS in public places can be greatly reduced by smoking bans. A recent study about the analysis acute coronary events in Italy before and after the implementation of the smoking ban in January 2005 found a statistically significant reduction  in acute coronary events, amounting to as much as approximately 11% in people aged 35–64 years and approximately 8% in those aged 65–74 years.
those aged 65–74 years.


In infants and young children, exposure to SHS increases the risk of sudden infant death syndrome, acute lower respiratory tract infections, chronic respiratory symptoms, middle ear disease, reduced pulmonary function and asthma. There is also some evidence that exposure to SHS during childhood may cause lymphoma and brain tumours. Studies in the Region have attributed 25% of all sudden infant death syndrome deaths to SHS and indicate that SHS increases the number of asthma episodes by 6–10%, depending on the underlying smoking prevalence. As a recognized human carcinogen, no level of SHS exposure is considered free of risk.
In infants and young children, exposure to SHS increases the risk of sudden infant death syndrome, acute lower respiratory tract infections, chronic respiratory symptoms, middle ear disease, reduced pulmonary function and asthma. Some evidence were found that exposure to SHS during childhood may cause lymphoma and brain tumours. Studies in the Region have attributed 25% of all sudden infant death syndrome deaths to SHS. The studies also indicated that SHS increases the number of asthma episodes by 6–10%, depending on the underlying smoking prevalence. As a recognized human carcinogen, no level of SHS exposure is considered to be free of risk.


Recent estimates of children’s exposure to SHS come from the Global Youth Tobacco Survey (GYTS), conducted among young people aged 13–15 years living in countries of central and eastern Europe, central Asia, the Caucasus and the Balkans. According to this study, the proportion of 13–15-year-olds exposed to SHS at home ranged from 37% (in the Czech Republic) to over 90% (in Armenia, the Balkan countries and Georgia), while exposure to SHS outside the home was comparatively higher, ranging from 65% to 96%. Even in countries with relatively low levels of exposure in the home, exposure outside the home is comparatively high. For western Europe, various studies from the late 1990s indicated that the proportion of children aged 0–4 years exposed to SHS at home lay between 20% (Netherlands) and 35% (England), with higher levels often seen in older children.
Recent estimates of children’s exposure to SHS come from the Global Youth Tobacco Survey (GYTS), conducted among young people aged between 13–15 years living in countries of central and eastern Europe, central Asia, the Caucasus and the Balkans. According to this study, the proportion of 13–15-year-olds exposed to SHS at home ranged from 37% (in the Czech Republic) to over 90% (in Armenia, the Balkan countries and Georgia), while the exposure to SHS outside the home was comparatively higher, ranging from 65% to 96%. Even in countries with relatively low levels of exposure in the home, the exposure outside the home is comparatively high. For western Europe, various studies from the late 1990s indicated that the proportion of children aged 0–4 years exposed to SHS at home lay between 20% (Netherlands) and 35% (England), with higher levels often seen in older children.


Unlike some other public health hazards, exposure to SHS is easily preventable. A number of countries worldwide have implemented various forms of smoke-free policies, and research shows that these policies are successful. Smoke-free policies have led to dramatic decreases in exposure to SHS (up to 90% in low-exposure settings) as well as decreases in daily cigarette consumption and in smoking by young people<ref name="who"/>
Unlike many other public health hazards, exposure to SHS is rather easily preventable. A number of countries worldwide have implemented various forms of smoke-free policies, and research shows that these policies are successful. Smoke-free policies have led to dramatic decreases in exposure to SHS (up to 90% in low-exposure settings) as well as decreases in daily cigarette consumption and in smoking by young people<ref name="who"/>


===Exposure to products of indoor combustion===
===Exposure to products of indoor combustion===
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Solid fuels such as dung, wood, agricultural residues, grass, straw, charcoal and coal, which are often applied for cooking and heating are major sources of indoor air pollution. Combustion of such fuels emits a number of different pollutants, but the smallest particles, with a diameter of 2.5 μm or less, appear to have the greatest health-damaging potential. Especialy women and young children, who usually spend most of their time indoor, are particularly vulnerable. Globally, 52% of the 1.6 million annual deaths related to indoor air pollution in children aged 0–4 years are from the use of solid fuels.
Solid fuels such as dung, wood, agricultural residues, grass, straw, charcoal and coal, which are often applied for cooking and heating are major sources of indoor air pollution. Combustion of such fuels emits a number of different pollutants, but the smallest particles, with a diameter of 2.5 μm or less, appear to have the greatest health-damaging potential. Especialy women and young children, who usually spend most of their time indoor, are particularly vulnerable. Globally, 52% of the 1.6 million annual deaths related to indoor air pollution in children aged 0–4 years are from the use of solid fuels.


There is consistent evidence that exposure to indoor air pollution from indoor combustion increases the risk of pneumonia, chronic respiratory disease and lung cancer. There is also some evidence for associations with asthma, cataracts, tuberculosis, adverse pregnancy outcomes, ischemic heart disease and cancers of the nose and throat (24). The risks also depend partly on the age of those exposed.
There is consistent evidence indicating that, exposure to indoor air pollution from indoor combustion increases the risk of pneumonia, chronic respiratory disease and lung cancer. Evidence were also found for associations with asthma, cataracts, tuberculosis, adverse pregnancy outcomes, ischemic heart disease and cancers of the nose and throat (24). The risks also depend partly on the age of those exposed.


In 2005, the use of solid fuel for cooking in 25 countries of the Region, for which data were available ranged from just above 0% to almost 50%. In many countries of the central Asia, where solid fuel is quite frequently used, have recorded substantial drops compared to previous estimates. A characteristic of the use of solid fuel is that in virtually all countries, the proportion of children exposed in rural areas is many times higher than in cities; in some countries, nearly all the exposure is in rural populations.
In 2005, the use of solid fuel for cooking in 25 countries of the Region, for which data were available ranged from just above 0% to almost 50%. In many countries of the central Asia, where solid fuel is quite frequently used, have recorded substantial drops compared to previous estimates. A characteristic of the use of solid fuel is that in virtually all countries, the proportion of children exposed in rural areas is many times higher than in cities; in some countries, nearly all the exposure is in rural populations.
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==Synergies between climate change mitigation and cleaning the air==
==Synergies between climate change mitigation and cleaning the air==


There are a number of links between air pollution, factors affecting the climate and health. The main greenhouse gases (carbon dioxide, methane) are emitted in the same processes that produce air pollutants hazardous to health. Many air pollutants of health concern, such as fine particles or ozone, affect climate directly. On the other hand, air pollutants are often modified by climatic factors (such as temperature and precipitation). For example, temperature modifies the chemical reactions that synthesize ozone, while wind modifies the long-range dispersion of PM. Climatic conditions, such as precipitation or flooding, modify the growth of mould and bacteria and these changes affect the spatial and temporal distribution of allergenic plants. There is growing recognition of the synergies, gains in efficiency and co-benefits of integrated policies and action to mitigate climate change and to alleviate health problems. To achieve the greatest health gains, policies to mitigate climate change should include control of a wider range of combustion-related pollutants in addition to carbon dioxide emissions. A substantial proportion of the major causes of global warming also directly damage health, and it is important to be aware that control of some combustion-related pollutants may lead to quick reductions in global warming.
There are a number of links between air pollution, factors affecting the climate and health. The main greenhouse gases (carbon dioxide, methane) are emitted in the same processes that produce air pollutants hazardous to health. Many air pollutants of health concern, such as fine particles or ozone, affect climate directly. On the other hand, air pollutants are often modified by climatic factors (such as temperature and precipitation). For example, temperature modifies the chemical reactions that synthesize ozone, while wind modifies the long-range dispersion of PM. Climatic conditions, such as precipitation or flooding, modify the growth of mould and bacteria and these changes affect the spatial and temporal distribution of allergenic plants. There is growing recognition of the synergies, gains in efficiency and co-benefits of integrated policies and action to mitigate climate change and to alleviate health problems. In order to achieve the greatest health gains, policies to mitigate climate change should include control of a wider range of combustion-related pollutants in addition to carbon dioxide emissions. A substantial proportion of the major causes of global warming also directly damage health, and it is important to be aware that control of some combustion-related pollutants may lead to quick reductions in global warming.


There is also a potential risk of either the creation, or an increased risk, of health effects from air pollution if climate change mitigation policies do not address health directly. Examples of such potential threat include the proliferation of diesel cars not equipped with appropriate exhaust control systems. While such cars emit less carbon dioxide than petrol-powered cars, they create more fine PM. Similarly, reducing air circulation through buildings to conserve energy could increase the risk of mould.
There is also a potential risk of either the creation, or an increased risk of health effects from air pollution if climate change mitigation policies do not address health directly. Examples of such potential threat include the proliferation of diesel cars not equipped with appropriate exhaust control systems. While such cars emit less carbon dioxide than petrol-powered cars, they create more fine PM. Similarly, reducing air circulation through buildings to conserve energy could increase the risk of mould.


The consequences of climate change on respiratory disease are difficult to predict but will depend, in part, on the specific region concerned and population-level characteristics. Diseases expected to be affected include asthma, rhinosinusitis, chronic obstructive pulmonary disease and respiratory tract infections. Policies intended to mitigate climate change in various sectors would generally appear to result in net benefits for respiratory health, mainly by reducing population exposure to hazardous air pollutants.<ref name="who"/>
The consequences of climate change on respiratory disease are difficult to predict but will, however, depend in part, on the specific region concerned and population-level characteristics. Diseases expected to be affected include asthma, rhinosinusitis, chronic obstructive pulmonary disease and respiratory tract infections. Policies intended to mitigate climate change in various sectors would generally appear to result in net benefits for respiratory health, mainly by reducing population exposure to hazardous air pollutants.<ref name="who"/>


==Air quality and health: policy analysis==
==Air quality and health: policy analysis==


This policy assessment of outdoor air quality, dampness and mould and SHS is based on responses to the WHO survey on EH policies received from 38 Member States. As with other topics, not all countries submitted information for all policies. The majority completed questionnaires concerning outdoor air quality and SHS, but only 23 countries did so for the dampness and mould questionnaires. No EurG-C countries provided information on this topic.
This policy assessment of outdoor air quality, dampness and mould and SHS is based on responses to the WHO survey on EH policies that was received from 38 Member States. As with other topics, not all countries submitted information for all policies. The majority completed questionnaires concerning outdoor air quality and SHS, but only 23 countries did so for the dampness and mould questionnaires. No EurG-C countries provided information on this topic.


The policy profiles for these three topics are shown in the figure below. All country groups reported having outdoor air quality policies and a significant number had SHS policies. To some extent, this may reflect the existence of strong EU legislation, the WHO Framework Convention on Tobacco Control and WHO’s air quality guidelines. Implementation of policies addressing dampness and mould generally showed the lowest score – which is of concern, given the importance of this health issue.<ref name="who"/>
The policy profiles for these three topics are shown in the figure below. All country groups reported having outdoor air quality policies and a significant number had SHS policies. To some extent, this may reflect the existence of strong EU legislation, the WHO Framework Convention on Tobacco Control and WHO’s air quality guidelines. Implementation of policies addressing dampness and mould generally showed the lowest score – which is of concern, given the importance of this health issue.<ref name="who"/>
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====Objectives, scope and type of policy measures====
====Objectives, scope and type of policy measures====


Most policy measures covering outdoor air quality aim to ensure compliance with national air quality standards and thresholds for pollutants emission at the source. For all EU member states and two thirds of the countries of south-eastern Europe, these policies follow EU regulations and other international commitments. The link with international regulations is less common in EurG-D countries. On the other hand, direct reference to the health objectives of the policies is more often reported from the latter group of countries than from the others. In 90% of responding countries, national ambient air quality policies cover pollutants which fall within the scope of EU legislation – PM, ozone, nitrogen dioxide and sulfur dioxide. Policies in more than one third of countries cover additional pollutants: heavy metals, black smoke, total suspended PM, volatile organic compounds, fluorides, chlorinated substances and dioxins. Only a few countries in EurG-D group have introduced standards for the inhalable, health-relevant proportion of PM (PM<sub>10</sub> or PM<sub>10</sub>).
Most policy measures regarding outdoor air quality aim to ensure compliance with national air quality standards and thresholds for pollutants emission at the source. For all EU member states, and two thirds of the countries of south-eastern Europe, these policies follow EU regulations and other international commitments. The link with international regulations is less common in EurG-D countries. On the other hand, direct reference to the health objectives of the policies is more often reported from the latter group of countries than from the others. In 90% of responding countries, national ambient air quality policies cover pollutants which fall within the scope of EU legislation – PM, ozone, nitrogen dioxide and sulfur dioxide. Policies in more than one third of countries cover additional pollutants: heavy metals, black smoke, total suspended PM, volatile organic compounds, fluorides, chlorinated substances and dioxins. Only a few countries in EurG-D group have introduced standards for the inhalable, health-relevant proportion of PM (PM<sub>10</sub> or PM<sub>10</sub>).


For dampness and mould, EU member states tend to have comprehensive measures in place, in particularly within the EurG-A grouping. In the EurG-D countries, building codes and regulations for the construction and maintenance of new buildings seem to be the most widespread policies. Policies directly addressing damp and mould in existing buildings are common in EurG-A but rare in the other countries.
For dampness and mould, EU member states tend to have comprehensive measures in place, in particularly within the EurG-A grouping. In the EurG-D countries, building codes and regulations for the construction and maintenance of new buildings seem to be the most widespread policies. Policies directly addressing damp and mould in existing buildings are common in EurG-A but rare in the other countries.
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[[file:scopepolicydampmould.png|thumb|250px|Scope of policy measures on damp and mould, by country grouping<ref name="who"/>]]
[[file:scopepolicydampmould.png|thumb|250px|Scope of policy measures on damp and mould, by country grouping<ref name="who"/>]]


Figure below shows the distribution of policy instruments on outdoor and indoor air quality. Outdoor air quality is subject to almost twice as many policy instruments as indoor air, and legislation is the predominant tool. Several countries have action plans or programmes for outdoor air and SHS; this is less common for damp and mould, where policy is often based on softer measures such as government regulations or guidelines and voluntary standards. Government regulations or guidelines are particularly infrequent relating to SHS.
The figure here shows the distribution of policy instruments on outdoor and indoor air quality. Outdoor air quality is subject to almost twice as many policy instruments as indoor air, and legislation is the predominant tool. Several countries have action plans or programmes for outdoor air and SHS; this is less common for damp and mould, where policy is often based on softer measures such as government regulations or guidelines and voluntary standards. Government regulations or guidelines are particularly infrequent relating to SHS.


Differences in the spread of instruments relating to outdoor air quality, dampness and mould and SHS largely reflect the impact of EU policies and legislation on the entire WHO European Region in those areas where EU legislation is strong. Air quality directives are the most important driving forces for the improvement of outdoor air quality policies, even outside the EU. Several of the EurG-C countries, such as Croatia and Turkey, as well as the Republic of Moldova (EurG-D), are working to harmonize their air quality legislation with that of the EU.<ref name="who"/>
Differences in the spread of instruments relating to outdoor air quality, dampness and mould and SHS largely reflect the impact of EU policies and legislation on the entire WHO European Region in those areas where EU legislation is strong. Air quality directives are the most important driving forces for the improvement of outdoor air quality policies, even outside the EU. Several of the EurG-C countries, such as Croatia and Turkey, as well as the Republic of Moldova (EurG-D), are working to harmonize their air quality legislation with that of the EU.<ref name="who"/>

Latest revision as of 09:40, 15 June 2012

This text is taken from the WHO report "Health and Environment in Europe: Progress Assessment", 2010, ISBN 978 92 890 4198 0. [2]

Regional priority goal III: We aim to prevent and reduce respiratory disease due to outdoor and indoor air pollution, thereby contributing to a reduction in the frequency of asthmatic attacks, in order to ensure that children can live in an environment with clean air.[1]

Key messages

  • The incidence of infant death from respiratory disease has been falling in most countries but is still significant (12% of infant deaths overall), particularly in the eastern part of the Region. Asthma and allergies are important and increasing causes of childhood illness.
  • Air pollution and especially particulate matter, causes significant health problems throughout the Region, reducing life expectancy in more polluted areas by over one year.
  • After substantial decreases in outdoor air pollution in most of the Region in the 1990s, progress in the last decade has been minimal.
  • WHO guidelines and EU legislation form the basis for national policies on healthy air throughout Europe. They also drive new policy development, such as that related to second-hand tobacco smoke.
  • Damp and mould are now established as major indoor air quality problems which disproportionately affect the health of disadvantaged populations. Although approaches to reduce and eliminate damp and mould from buildings exist, relevant public policies need to be strengthened.
  • Even though regulations, such as, introducing spaces free of tobacco smoke have proved highly efficient in reducing the health impacts of tobacco, they have yet to be introduced or developed in large parts of the Region.[1]

Clean air and its public health significance – new insights

Knowledge about the links between health and air quality has significantly advanced in the past two decades. There is more evidence about the role of pollutants in the aetiology of respiratory diseases and new insights have been gained into the impacts of fine particulate matter on cardiovascular health. Over hundreds of studies around the world confirm the association of mortality, or hospital admissions, with levels of the most common urban air pollutants. The results of this research combined with data on air quality in Europe, indicate that the pollution of air with fine particulate matter leads to a nine-month shortening of life expectancy in Europe. New studies among children have indicated that exposure not only increases the prevalence of respiratory symptoms, but also raises the incidence of new respiratory diseases. New studies also indicated that substantial gains in public health resulting from improvements in air quality, for example, the attribution of 15% of the overall increase in life expectancy to the reduction of fine particulate matter in the United States. This evidence has been reviewed and summarized by WHO in the updated Air quality guidelines, and it is being used to design the new approaches and regulations to reduce the health risks of pollution.

New evidence is accumulating on the burden of disease due to indoor air pollution. The risks to health of exposure to second-hand tobacco smoke have been widely recognized and are reflected by the widespread programmes to eliminate tobacco smoke from indoor spaces. Other hazardsthat are common in indoor air, such as biological contaminants arising from damp and mould, have been well characterized by the newly published WHO Guidelines for indoor air quality – dampness and mould. An understanding of these links is an essential element of action to reduce the burden of disease and to benefit public health.

Considering this new research information, this section reviews the background patterns of diseases affected by common air pollutants, presents the distribution and trends in exposure in European populations, and characterizes the inherent risks and the opportunities for their reduction.[1]

The burden of respiratory disease

The rate of infant death from respiratory disease have fallen in all the sub-regions and in nearly all countries since the mid- to late-1990s. The present rates account for over 12% of total infant deaths, a substantial burden.

Average post-neonatal death rates from respiratory diseases (per 1000 live births)[1]

A considerable variation could be observed across the Region, with a gradual increase in the death rate from west to east. The poorer economic and environmental situation in eastern Europe contributes to higher rates seen in that part of the Region. Several countries have virtually eliminated respiratory diseases as a cause of post-neonatal death, indicating the huge potential for further reductions in other countries.

There are noticeable differences in the causes of respiratory infections between various regions of Europe. For instance, bacterial infections are more common in developing countries while viral infections cause most acute lower respiratory infections in developed countries. In temperate European countries, there is a marked seasonal variation in acute lower respiratory infections with a significant rise in incidence in winter months falling to relatively low levels in summer.

Post-neonatal infant death rates due to respiratory diseases in 25 WHO European Member States, 2004−2007 (In Austria, Finland, Luxembourg and Slovenia, the reported mortality is 0.)[1]

Substantial evidence have been found concerning the adverse effects of air pollution on pregnancy outcomes and infant death. This is sufficient to infer a causal relationship between particulate air pollution and respiratory deaths in the post-neonatal period, as well as, with adverse effects on the development of lung function. An increased incidence can be inferred of upper and lower respiratory symptoms (many of which are likely to be symptoms of infection) due to exposure. Older children are also adversely affected by air pollution, and their susceptibility needs to be considered when air pollution regulations are developed.

The effects are attributed to various combustion-related outdoor air pollutants, as well as, poor indoor air quality which arises in particular from dampness and mould, the use of solid fuel for cooking and heating, tobacco smoke, infectious agents and allergens.

Air pollution is also associated with chronic respiratory diseases which often begins in childhood. Two major chronic respiratory diseases are asthma and allergic rhinoconjunctivitis6. Globally, the prevalence of asthma and allergies has increased over the last few decades. Asthma has now become the most common chronic disease in children and is one of the major causes of hospitalization for those aged under 15 years. The increasing prevalence of allergic diseases in children throughout Europe is no longer restricted to specific seasons or environments. The greatest increases are generally seen in urban areas.[1]

Between 1999 and 2004, asthma prevalence rates in Europe ranged from approximately 5% to 20% in children, aged 6–7 years and from approximately 5% to 25% in children aged 13–14 years. Allergic rhinoconjunctivitis shows slightly less variation, with a prevalence of approximately 5% to 10% in children aged 6–7 years and from approximately 5% to 20% among children aged 13–14 years. The rates tended to be higher in older children for both asthma and allergies, and wide within-country ranges were often seen in those countries where sufficient data were available. Overall, the correlation between the prevalence of these two conditions was high.

Asthma symptoms adversely affect young patients in a number of ways including schoolwork and social activities. Early diagnosis and appropriate treatment is vital, as this leads to much better disease control and outcomes. Good management of asthma and allergies, for example, by reducing the level of exposure to common risk factors and providing appropriate medication, can control the disorder which can enable people to enjoy a high quality of life.

Effects of asthma on patients in EU countries, 2005[1]

There is a complex interaction between genetic and environmental factors in the development of both asthma and allergies. There is evidence of a causal relationship between exposure to air pollution and exacerbation of asthma, mainly due to exposure to particulate matter and ozone. The incidence of allergic symptoms in children is associated with exposure to allergens in indoor environments, that may include smoke from fires, damp and mould, dust mites, allergens from pets and second-hand tobacco smoke.

Children, who are more frequently exposed to poor indoor air may subsequently be at greater risk of being affected by outdoor pollutants. Factors including lifestyle, dietary habits, socioeconomic status and climatic factors may also influence the rates of asthma and aller gies.

Asthma continues to affect many individuals into adulthood, which indicates that the prevalence of asthma in adults is also high. However, not all chronic respiratory diseases start in childhood. Chronic lung diseases that cause limitations in lung airflow (often collectively referred to as chronic obstructive pulmonary disease) tend to begin in mid-life. Although mortality from these diseases is falling in the Region, it still causes 4% of all deaths and contributes to 5% of the overall burden of disease. Globally, their burden is increasing and, should current trends persist, they are projected to become the third leading cause of death by the year 2030. Currently, the most important risk factors for chronic obstructive pulmonary disease are tobacco-smoking, indoor and outdoor air pollution, and occupational exposure to dusts and chemicals.

It has only become fully apparent in the last decade that air pollution, especially of fine particulates, plays a major role in cardiovascular disease. More than half (52%) of deaths, and 23% of the overall burden of disease in the Region, arises from cardiovascular disease. Even a relatively small increases in the risk of cardiovascular disease will translate into huge absolute numbers of additional people suffering more severely from the disease.[1]

Outdoor air pollution and its impact on health in Europe

A number of outdoor air pollutants affect on health. The impacts of the two widespread pollutants evaluated here, particulate matter and ozone are the most known but other pollutants (volatile organic compounds, nitrogen oxide, sulfur oxide, etc.) should also be considered for policy action.

Large amounts of particulate matter (PM) are generated by a number of activities by human beings. Since particles can travel hundreds and thousands of kilometres in the air and are partly created from gaseous pollutants in the atmosphere, their effects can be seen far from the source. PM consists of solid and liquid particles that vary in their physical and chemical properties and that are classified by particle diameter (in micrometres – μm). When inhaled, PM10 particles (with a diameter of less than 10 μm) penetrate deep into the respiratory system. Finer particles (with a diameter of less than 2.5 μm) then go on to penetrate the lungs and pass into the bloodstream and are carried into other body organs. Concerned that these particles cause a wide range of health impacts, WHO has developed guidelines addressing their risks.

Long-term average exposure to PM is associated with both the risks of chronic effects on children’s health, such as impaired development of lung function, and the frequency of acute effects, such as the aggravation of asthma or incidence of respiratory symptoms.Young children, including unborn babies, are particularly sensitive to air pollutants. Exposure to PM is also associated with increased hospital admissions and mortality in adults. The risk increases linearly with the concentration of pollution, and there is no evidence to suggest a threshold for PM below which no adverse health effects would occur.

Data from year 2007 showed that there are important disparities in P10 exposure in the Region: average country levels varied from 16 μg/m3 (Finland and Ireland) to 45–52 μg/m3 (Bulgaria, Romania and Serbia) and 72 μg/m3 in Turkey. Within-country differences were also substantial. In total, over 92% of the urban population for which PM10 data are available live in cities where the WHO air quality guideline for PM10 is exceeded.[1]

[[file:emissionsectorseu27.png|thumb|250px|Contribution of key sectors to emission of PM in the EU27, 2007[1]


WHO air quality guidelines for particulate matter

Annual average 24-hour mean (not to be exceeded >3 days/year)
PM2.5 10 μg/m3 25 μg/m3
PM10 20 μg/m3 50 μg/m3

Overall, the regional average of urban PM10 did not change substantially in the period 1997–2007. Concentrations of another common urban air pollutant, nitrogen dioxide, fell more consistently, but the reduction was small. This contrasts with the pronounced downward trend evident for sulfur dioxide, indicating that policies aimed at the reduction of sulfur emissions have been more effective than those addressing PM or nitrogen emissions.

WHO’s analysis which was based on data from the late 1990s, indicates that throughout the Region around 700 deaths from acute respiratory infections can be attributed to PM10 exposure annually in children aged 0–4 years. Quantifying the effects of PM exposure on illness is more difficult, but a reduction of PM10 exposure to 20 μg/m3 could be associated with a 7% decrease in the incidence of coughs and lower respiratory symptoms and a 2% decrease in respiratory-related hospital admissions in children aged under 15 years. A decrease to 10 μg/m3 is expected to reduce the number of days that children aged 5–14 years suffer lower respiratory symptoms (wheezing, chest tightness, shortness of breath and coughs) by 1.9 days per year per child.

Estimates of the health burden from PM exposure in adults are dominated indicated by the increase in the risk of mortality due to long-term exposure to fine PM2.5. People in Europe are generally unaware of the life-shortening consequences, for them, of air pollution. Current exposure to PM from anthropogenic sources leads to the loss of 8.6 months of life expectancy in Europe – from around 3 months in Finland to more than 13 months in Belgium. The most recent estimates of impacts of PM on mortality, based on PM10 and PM2.5 monitoring data in 40 European countries, indicate that close to 500 000 deaths per year are accelerated due to exposure to ambient PM in those countries. The distribution of these deaths is mapped in a figure below. It is important to note that there is no information on PM levels in many parts of the Region, mainly in the east and including the newly independent states, but approximate estimates for these countries suggest that the burden of disease related to PM exposure will be considerable.[1]

Percentage of urban population exposed to various annual average PM10 levels in countries with PM10 data, 2007[1]
Annual average concentrations of PM10, nitrogen dioxide and sulfur dioxide monitored in urban background locations, 1997-2007[1]
Premature deaths attributed to PM2.5, 2005 (attributable annual mortality per 10 000 people)[1]

A significant reduction in PM to around 50% of current levels could be achieved if all currently technically feasible emission reduction measures were implemented (the maximum feasible reduction scenario). Although PM10 monitoring data from the 1990s are very scarce in Europe, they do indicate that in the previous decade a significant reduction in pollution has been achieved. For example, mean PM10 measured in United Kingdom cities fell from approximately 36 μg/m3 at the beginning of the 1990s to 23 μg/m3 by 2000.

Ozone is another outdoor air pollutant that causes substantial deaths and illness in the Region. Ozone in lower levels of the atmosphere originates largely from human activity and is not only harmful to humans but has adverse effects on materials and vegetation. It is also a greenhouse gas when in the upper troposphere. Children may be more exposed than adults because of their higher rate of physical activity, the greater amount of time they spend outside and their higher metabolic rate.

Ozone is linked to a number of health problems. Short-term exposure can increase respiratory deaths and the incidence of respiratory symptoms. The consequences of long-term exposure are less well-established but suggestive evidence points to further negative effects.

Despite indications of decreasing frequency of days with high ozone concentrations across much of Europe, ozone continues to contribute substantially to regional health burdens. High ozone concentrations (above 70 μg/m3) are associated with approximately 21 000 deaths and 14 000 respiratory hospital admissions annually in the member states of the EU since 2004 (EU25). The risk is proportional to the indicator which gives the value of the sum of the daily maximum eight-hour mean over 35 parts per billion (SOMO35), presented in the figure below for current O3 levels modelled for 2000 and 2020. High ozone levels aggravate respiratory conditions, with the magnitude of the impact in the range of 8–108 million person-days annually in EU countries.

Model estimates of rural ozone concentrations expressed as SOMO35 for 2000 (left) and 2020 (right)(Risks to health are expected to be proportional to SOMO35)[1]

Current policies are only expected to reduce ozone-related mortality by about 1000 deaths or fewer. Reductions in illness are expected to be greater, with particular benefits in the reduction of cough and lower respiratory symptoms in children (by an estimated 40%). Implementation of all technically feasible pollution reduction measures would, however, halve the current mortality by 2020.[1]

Exposure to indoor air pollution

Second-hand tobacco smoke

Children, adolescents and also adults can be exposed to tobacco smoke indirectly through second-hand tobacco smoke (SHS). SHS is defined as the involuntary or passive breathing of air which is contaminated with tobacco smoke by someone who is not smoking. It is a dominant form of indoor air pollution in spaces where tobacco is smoked and even where areas are properly ventilated.

Tobacco-smoking accounts for at least 30% of all cancer deaths in the general population as well as for a substantial proportion of cardiovascular and respiratory disease. It is well-established that exposure to SHS creates a huge burden to health. The most recent calculations have indicated that more than 72,000 people in the EU25 alone die each year due to exposure to SHS inside the home environment. Along with the exposure at home, workplace exposure to SHS is also linked to an increased risk of death. In 2008, in the EU, 6000 deaths were attributable to SHS in offices, bars and restaurants, 40% of which were in non-smoking staff. These estimates do not include the health burden of customers. The burden of illness related to exposure to SHS in public places can be greatly reduced by smoking bans. A recent study about the analysis acute coronary events in Italy before and after the implementation of the smoking ban in January 2005 found a statistically significant reduction in acute coronary events, amounting to as much as approximately 11% in people aged 35–64 years and approximately 8% in those aged 65–74 years.

In infants and young children, exposure to SHS increases the risk of sudden infant death syndrome, acute lower respiratory tract infections, chronic respiratory symptoms, middle ear disease, reduced pulmonary function and asthma. Some evidence were found that exposure to SHS during childhood may cause lymphoma and brain tumours. Studies in the Region have attributed 25% of all sudden infant death syndrome deaths to SHS. The studies also indicated that SHS increases the number of asthma episodes by 6–10%, depending on the underlying smoking prevalence. As a recognized human carcinogen, no level of SHS exposure is considered to be free of risk.

Recent estimates of children’s exposure to SHS come from the Global Youth Tobacco Survey (GYTS), conducted among young people aged between 13–15 years living in countries of central and eastern Europe, central Asia, the Caucasus and the Balkans. According to this study, the proportion of 13–15-year-olds exposed to SHS at home ranged from 37% (in the Czech Republic) to over 90% (in Armenia, the Balkan countries and Georgia), while the exposure to SHS outside the home was comparatively higher, ranging from 65% to 96%. Even in countries with relatively low levels of exposure in the home, the exposure outside the home is comparatively high. For western Europe, various studies from the late 1990s indicated that the proportion of children aged 0–4 years exposed to SHS at home lay between 20% (Netherlands) and 35% (England), with higher levels often seen in older children.

Unlike many other public health hazards, exposure to SHS is rather easily preventable. A number of countries worldwide have implemented various forms of smoke-free policies, and research shows that these policies are successful. Smoke-free policies have led to dramatic decreases in exposure to SHS (up to 90% in low-exposure settings) as well as decreases in daily cigarette consumption and in smoking by young people[1]

Exposure to products of indoor combustion

Solid fuels such as dung, wood, agricultural residues, grass, straw, charcoal and coal, which are often applied for cooking and heating are major sources of indoor air pollution. Combustion of such fuels emits a number of different pollutants, but the smallest particles, with a diameter of 2.5 μm or less, appear to have the greatest health-damaging potential. Especialy women and young children, who usually spend most of their time indoor, are particularly vulnerable. Globally, 52% of the 1.6 million annual deaths related to indoor air pollution in children aged 0–4 years are from the use of solid fuels.

There is consistent evidence indicating that, exposure to indoor air pollution from indoor combustion increases the risk of pneumonia, chronic respiratory disease and lung cancer. Evidence were also found for associations with asthma, cataracts, tuberculosis, adverse pregnancy outcomes, ischemic heart disease and cancers of the nose and throat (24). The risks also depend partly on the age of those exposed.

In 2005, the use of solid fuel for cooking in 25 countries of the Region, for which data were available ranged from just above 0% to almost 50%. In many countries of the central Asia, where solid fuel is quite frequently used, have recorded substantial drops compared to previous estimates. A characteristic of the use of solid fuel is that in virtually all countries, the proportion of children exposed in rural areas is many times higher than in cities; in some countries, nearly all the exposure is in rural populations.

Proportion of 13−15-year-olds exposed to SHS inside and outside the home, 2002–2007[1]

Within the Region, the burden of disease attributable to risk factors is related to the use of solid fuel is extremely unequally distributed. The highest burden of respiratory illness among children aged 0–4 years occurs in EurB countries,7 both in terms of mortality and illness. These estimates should be interpreted with caution owing to the scarcity of household-level data on use of solid fuels in the other regions.[1]

Percentages of children aged from 0−14 years living in homes using solid fuels for cooking, WHO European Region, 2005[1]


Mortality and morbidity attributable to cooking with solid fuels in children aged 0–4 years, WHO European Region, 2006

WHO epidemiological subregion Burden of disease study, 2006
Deaths ('000) DALYs('000)
EurA 0 0
EurB 11.6 319
EurC <1 12.5

Moving towards cleaner fuels or towards combustion technologies is the preferred way of preventing the health effects of exposure to the products of indoor combustion. Such a move increases energy efficiency and is often consistent with approaches to reduce greenhouse gas emissions and ambient air pollution.[1]

Exposure to damp

Exposure to damp in the home environment and to biological contaminants in indoor air arising from dampness is a strong and consistent indicator of risk for a number of respiratory illnesses, including asthma and respiratory symptoms such as cough and wheeze (28). Dampness facilitates the growth of moulds, fungi and bacteria which emit spores, cells, fragments and volatile organic compounds into the indoor air. Moreover, dampness initiates chemical and/or biological degradation of materials, which also causes indoor air pollution. Exposure to microbial contaminants is clinically associated with respiratory symptoms, allergies, asthma and immunological reactions. The risk of a range of respiratory symptoms increases on an approximate 50% among the residents of homes suffering from damp. Accordingly, WHO recently released the first guidelines regarding Indoor air quality – dampness and mould. European survey data have indicated that exposure to damp is a frequent health risk, with 18% of the EU population exposed in 2007 (vs. 19% in 2005 and 18% in 2006). Exposure varies a lot among countries, however, ranging in 2007 between 5% and 37%. Damp houses are more common in the new EU member states, although many of these also show a notable decrease in exposure over recent years.

International comparisons are difficult with current survey data so analysis has to focus on national trends. The capacity for international comparisons would be enhanced if procedures for data collection were standardized.

Proportion of total population living in homes with self-reported problems of damp, 2004–2007, and proportion of population in relative poverty living in homes with self-reported problems of damp, 2007[1]

The number of household members, activities such as cooking, laundering and bathing, the use of certain fuels for energy, indoor temperature, amount of insulation, climate, housing characteristics and especially the degree of ventilation, all affect the amount of water vapour in indoor air. As is to be expected, poorer population groups are more likely to live in homes with problems of damp in every country surveyed.

Dampness and condensation are connected to other housing quality indicators, and the rehabilitation of housing stock would go a long way towards reducing exposure to indoor air pollution as well as improving other aspects of quality of life. A focus on damp in the homes of poorer residents may yield the greatest health gains. Case studies from around Europe have demonstrated that there are a number of fairly straightforward ways of reducing exposure to damp and mould, which can be successful in a variety of climates.[1]

Two examples of successful programmes to reduce exposure to indoor pollutants

Mechanical ventilation in Sweden

Sweden, a country with a relatively cold climate, the impact of mechanical ventilation on indoor humidity, mite allergens and volatile organic compounds in 59 single-family dwellings has recently been assessed. Mechanical ventilation reduced exposure to all three indoor air health risks compared with natural ventilation. National and municipal programmes have been put in place in Sweden based on these findings.

Building standards in Israel

Israel is a country with a Mediterranean climate, passed a national thermal insulation standard in 1985 aimed at reducing the risk of surface condensation in dwellings. After implementation of the standard, the proportion of homes with condensation-related mould decreased by 25% and those with extreme mould growth by 20%. The enforcement of the standard created a change in the building market that led to improved building products and to better insulation in new buildings.

Synergies between climate change mitigation and cleaning the air

There are a number of links between air pollution, factors affecting the climate and health. The main greenhouse gases (carbon dioxide, methane) are emitted in the same processes that produce air pollutants hazardous to health. Many air pollutants of health concern, such as fine particles or ozone, affect climate directly. On the other hand, air pollutants are often modified by climatic factors (such as temperature and precipitation). For example, temperature modifies the chemical reactions that synthesize ozone, while wind modifies the long-range dispersion of PM. Climatic conditions, such as precipitation or flooding, modify the growth of mould and bacteria and these changes affect the spatial and temporal distribution of allergenic plants. There is growing recognition of the synergies, gains in efficiency and co-benefits of integrated policies and action to mitigate climate change and to alleviate health problems. In order to achieve the greatest health gains, policies to mitigate climate change should include control of a wider range of combustion-related pollutants in addition to carbon dioxide emissions. A substantial proportion of the major causes of global warming also directly damage health, and it is important to be aware that control of some combustion-related pollutants may lead to quick reductions in global warming.

There is also a potential risk of either the creation, or an increased risk of health effects from air pollution if climate change mitigation policies do not address health directly. Examples of such potential threat include the proliferation of diesel cars not equipped with appropriate exhaust control systems. While such cars emit less carbon dioxide than petrol-powered cars, they create more fine PM. Similarly, reducing air circulation through buildings to conserve energy could increase the risk of mould.

The consequences of climate change on respiratory disease are difficult to predict but will, however, depend in part, on the specific region concerned and population-level characteristics. Diseases expected to be affected include asthma, rhinosinusitis, chronic obstructive pulmonary disease and respiratory tract infections. Policies intended to mitigate climate change in various sectors would generally appear to result in net benefits for respiratory health, mainly by reducing population exposure to hazardous air pollutants.[1]

Air quality and health: policy analysis

This policy assessment of outdoor air quality, dampness and mould and SHS is based on responses to the WHO survey on EH policies that was received from 38 Member States. As with other topics, not all countries submitted information for all policies. The majority completed questionnaires concerning outdoor air quality and SHS, but only 23 countries did so for the dampness and mould questionnaires. No EurG-C countries provided information on this topic.

The policy profiles for these three topics are shown in the figure below. All country groups reported having outdoor air quality policies and a significant number had SHS policies. To some extent, this may reflect the existence of strong EU legislation, the WHO Framework Convention on Tobacco Control and WHO’s air quality guidelines. Implementation of policies addressing dampness and mould generally showed the lowest score – which is of concern, given the importance of this health issue.[1]

Policy profiles for outdoor air quality, dampness and mould and SHS[1]

Public governance

Objectives, scope and type of policy measures

Most policy measures regarding outdoor air quality aim to ensure compliance with national air quality standards and thresholds for pollutants emission at the source. For all EU member states, and two thirds of the countries of south-eastern Europe, these policies follow EU regulations and other international commitments. The link with international regulations is less common in EurG-D countries. On the other hand, direct reference to the health objectives of the policies is more often reported from the latter group of countries than from the others. In 90% of responding countries, national ambient air quality policies cover pollutants which fall within the scope of EU legislation – PM, ozone, nitrogen dioxide and sulfur dioxide. Policies in more than one third of countries cover additional pollutants: heavy metals, black smoke, total suspended PM, volatile organic compounds, fluorides, chlorinated substances and dioxins. Only a few countries in EurG-D group have introduced standards for the inhalable, health-relevant proportion of PM (PM10 or PM10).

For dampness and mould, EU member states tend to have comprehensive measures in place, in particularly within the EurG-A grouping. In the EurG-D countries, building codes and regulations for the construction and maintenance of new buildings seem to be the most widespread policies. Policies directly addressing damp and mould in existing buildings are common in EurG-A but rare in the other countries.

Scope of policy measures on damp and mould, by country grouping[1]

The figure here shows the distribution of policy instruments on outdoor and indoor air quality. Outdoor air quality is subject to almost twice as many policy instruments as indoor air, and legislation is the predominant tool. Several countries have action plans or programmes for outdoor air and SHS; this is less common for damp and mould, where policy is often based on softer measures such as government regulations or guidelines and voluntary standards. Government regulations or guidelines are particularly infrequent relating to SHS.

Differences in the spread of instruments relating to outdoor air quality, dampness and mould and SHS largely reflect the impact of EU policies and legislation on the entire WHO European Region in those areas where EU legislation is strong. Air quality directives are the most important driving forces for the improvement of outdoor air quality policies, even outside the EU. Several of the EurG-C countries, such as Croatia and Turkey, as well as the Republic of Moldova (EurG-D), are working to harmonize their air quality legislation with that of the EU.[1]

Types of policy instrument for outdoor air quality, dampness and mould and SHS[1]

Measures to assure compliance with policies

Penalties for infringements of regulations concerning outdoor air quality are the commonest measures, used by half of the EurG-A and all other countries. A proactive approach, aiming at setting remedial measures (such as action plans) to eliminate non-compliance is more often used in EU countries than in the other parts of the Region.

Measures to ensure policy compliance for outdoor air quality, by country grouping

Measures to ensure compliance with regulations related to dampness and mould are relatively consistent across the EU, with the majority of countries usually turning to remedial measures and action to reduce the risk of non-compliance. Such action is less common in EurG-D countries, which all use penalties for infringements of legal provisions.

Penalties for non-compliance with regulations related to SHS are the commonest measures across all countries. Typically, these measures involve the use of prosecutions, fines and other legal penalties. In addition, more than half of the countries across the Region may prohibit the use of buildings where there is reason to believe that regulations will not be followed. Legislation for smoke-free environments is relatively new and is still being implemented across Europe. Some examples of the effectiveness of smoke-free laws are given in the box below. In many countries, lobby groups, notably those representing bar and restaurant owners, have argued that smoking bans would affect their profits, which should be given greater priority than the health of their workers and customers. As a result, in more than half of the Member States, citizens and workers are still not fully protected from exposure to tobacco smoke in indoor workplaces and public places. Despite arguments and claims from the hospitality industry, experience in countries which have already implemented smoke-free laws shows that such legislation has not had a negative impact on business: indeed, restaurants are becoming more popular. A Eurobarometer survey of March 2009 found 84% of EU citizens in favour of smoke-free offices and other indoor workplaces, 77% in favour of smoke-free restaurants, and 61% supporting smoke-free bars and pubs.[1]

Implementation of smoke-free laws in the EU, June 2009[1]


Examples of the impact on health of laws restricting smoking

Recent studies have shown that the significant reduction in SHS resulting from regulations restricting smoking has also led to major improvements in respiratory health. For example, bar workers in Scotland reported a reduction in respiratory symptoms of 26% only one month after the introduction of such legislation. Furthermore, asthmatic bar workers reported a decrease in airway inflammation after three months.
While few data exist in Europe, a study in California showed that bartenders experienced a reduction in respiratory symptoms of 59% and a 78% decrease in sensory irritation symptoms just eight weeks after the implementation of such regulations in bars.
Laws restricting smoking have also been shown to reduce the prevalence of active smoking (36).

In Ireland, 46% of smokers claimed they were more likely to stop after the implementation of such legislation, and 80% of them later reported that they had stopped. In addition, 60% of smokers in Ireland stated that the new regulations had caused them to cut back on smoking by about four cigarettes a day. Similar results were also seen in Scotland, where 44% of former smokers claimed that the regulations had helped them to stop.

Impact of international policy processes on national standards

The EU Directive on ambient air quality and cleaner air for Europe was adopted in May 2008. Despite the WHO air quality guidelines, the permitted pollution levels from PM are significantly higher than WHO guideline levels. Nevertheless, if the targets and objectives of the Directive are achieved, significant reductions in risks for acute and chronic health effects from air pollution can be expected. Further efforts will be needed to achieve the WHO air quality guideline levels and the health protection they offer. The use of international standards for outdoor air quality creates the obligation on each EU country to comply and adapt their national laws accordingly. The influence of the EU Directive and of WHO’s guidelines has extended beyond the EU: more than two thirds of countries in the Region reported that they had adopted new or updated policies on outdoor air quality since 2004. For example, both Belarus and Turkey have recently begun monitoring PM10 levels.

Article 8 of the Framework Convention on Tobacco Control (FCTC), the world’s first public health treaty, has become a strong driver for the reduction of smoking and exposure to SHS in Europe. Ratification of the FCTC in 2004 has been followed by adoption of the Convention across the majority of WHO European Member States (48 out of 53). The goal of the FCTC is a complete smoking ban in all countries worldwide; actual implementation is, however, poor. Some countries in the EU are only in the first stages towards total smoking bans which, for many of them, mean a transitional period before stricter policies are enforced. Outside the EU, few countries have made significant progress towards creating smoke-free environments.

Until now, indoor air standards have been voluntary. The recent launch of WHO’s first indoor air quality guidelines on dampness and mould can, however, be expected to have a significant impact on future regional policies.[1]

Healthy public policy

Overall, all countries scored poorly for all the three air quality issues evaluated in this report for the most important dimensions of healthy public policy.

Policy evaluation and health accountability

Countries reported using various methods and tools for monitoring and evaluating outdoor air quality policy. Monitoring networks for ambient air quality are in place in many countries – an essential prerequisite for supporting the implementation and enforcement of air quality regulations. Monitoring in more than 30 countries across Europe encompasses a set of air pollutants at a representative selection of stations. Countries annually report data following the EU Directive on the exchange of information on ambient air quality. Belarus and Turkey have launched systematic countrywide monitoring of health-relevant pollutants such as PM, and the Russian Federation has recently put in place the necessary legal framework. Towards the east of the Region and in the EurG-D countries, the monitoring of air pollution and (as important) reporting of information to public databases are less transparent. This poses significant challenges for the preparation of information and its effective use in policy.

Advances in monitoring and in air quality databases allow regular assessments to be made of the effectiveness of policy implementation. Overall, around half of all European countries, but only one in six of the reporting countries in the EurG-D group, use specific indicators coupled with targets to measure progress towards policy objectives. In the western Europe, indicators of air quality are now regularly assessed. The adoption of Directive 2008/50/EC on ambient air quality shifted the focus of regulation from assessing the state of the environment to health-relevant integrated management (39). This will enhance the health accountability of air quality policy.

Measures to ensure policy accountability for health in SHS policies are often limited. While more monitoring and periodic reports appear to be available in EU countries than in EurG-C and EurG-D countries, the overall monitoring, reporting and systematic evaluation of policy measures still remain weak across the Region. The monitoring of policies on dampness and mould and evaluation of the health impacts of these policies remain in their infancy throughout the Region. More generally, the use of health impact assessments as a standard tool in air quality and health policy, coupled with follow-up programmes focusing on health consequences is urgently needed across the Region. When implemented, these will help increase the integration and accountability of health policy in air quality regulations.[1]

Health sector involvement in intersectoral policy action

Countries in the EurG-D grouping reported a higher level of health sector involvement in outdoor air quality policy formulation than other parts of the Region, especially EurG-A countries, where only half report any health sector involvement at that stage of the policy process. To some extent, this could be an effect of the traditional division of responsibilities and the role of the sanitary-epidemiological system in the east of the Region, and the assignment of responsibilities related to outdoor air quality to the environment sector in EU countries. EurG-D countries also report a much greater involvement of the health system in outdoor air quality monitoring, evaluation and enforcement than in other parts of the Region. While, potentially, this should assure the health relevance of the policies and action, their restricted scope and the obsolete methods of air quality monitoring limit the effectiveness of action by the health sector.

EurG-D countries also reported the highest health sector involvement in relation to the implementation, evaluation and enforcement of policies related to dampness and mould. However, the scores are about 30% lower overall, indicating that not enough attention is being paid to this problem. Figure below shows that between-country patterns of health sector involvement in SHS policies – a core mandate of health authorities – differ significantly from the patterns related to outdoor air quality. Health sector involvement is quite high throughout EurG-A, EurG-B and EurG-C countries. In EurG-D countries, however, the level of health sector involvement in SHS policy evaluation, control and enforcement is low. Since, in contrast to outdoor air quality, SHS is predominantly a health issue, this low level involvement of the health sector may indicate a low priority being given to SHS in EurG-D countries.[1]

Equity considerations

Perhaps with the slight exception of policies related to SHS, there is little evidence that the needs of vulnerable groups are considered in the European policies reported on air quality and health. With a few exceptions, consideration of vulnerable groups remains particularly low in relation to policies addressing damp. This contrasts with the recognition, that residents of poor housing experience a higher frequency of problems with damp.

Involvement of the health sector in the policy cycle for outdoor air quality[1]
Involvement of the health sector in the policy cycle for SHS[1]

It might be argued, that, the lack of equity considerations in outdoor air quality policy may be because good outdoor air quality is treated as a universal good, with measures to improve air quality benefitting everybody. Nevertheless, for the EurG-C and EurG-D countries, given the need for huge investments in outdoor air quality monitoring and, in particular, in remedial measures where resources are limited, it is possible that staged action targeting specific population subgroups, such as, poorer neighbourhoods within big cities might offer the greatest health and environment benefits in the shortest time.

Smoke-free environments are now becoming a greater focus of policy and society in many European countries, and vulnerable groups should become a priority of those policies. Such groups are, however, still not considered often enough (although more commonly than in the other aspects of policies on clean air). The lack of focus on children, pregnant women and workers in measures to prevent exposure to SHS, reported by many countries, emphasizes the need for an urgent action.[1]

Reducing the health effects of dampness and mould in indoor air

A WHO Working Group reviewing interventions in order to reduce the impacts on health of damp and mould has identified a few projects addressing vulnerable groups. It appears that consideration of the particular needs of vulnerable and underprivileged groups is a part of intervention programmes in some of the Nordic countries and the United Kingdom. Equity is also a key pillar of the newly launched Norwegian strategy for prevention and treatment of asthma and allergic diseases.
A specific case from the United Kingdom is the Warm Front initiative, which aims to improve the health of low-income households in cold dwellings by increasing the indoor temperature through the installation of draught-stripping, insulation and gas central heating. Warm Front was beneficial in increasing the indoor temperature and thermal comfort, with the householders feeling most comfortable at 19 °C, and in decreasing relative humidity and mould.
Universal measures that mitigate the equity aspects of damp and mould were also explored by the WHO Working Group. Israel provides a good example (46). A new thermal insulation standard for buildings was introduced in 1985, when there was high public awareness of the problem of damp and mould in many Israeli dwellings whose inhabitants mainly belonged to low-to-medium income groups. A universal law was introduced requiring more insulation in newly constructed buildings. The policy resulted in a drop in damp and mould problems in new dwellings. However, no requirements for improving thermal insulation were imposed on existing buildings.
Considerations of specific population groups in SHS policies[1]

Transparency and communication

Country groups differ in the measures they take to inform people about the hazards of air pollution and the steps that can be taken to avoid exposure and health risks. EurG-D countries have scored significantly worse at providing information to their populations for all three issues and especially so in relation to outdoor air quality. This may partly be due to cultural and historical reasons, and, the relative importance governments give to informing the public. Information on the health effects of, and mitigating measures for, SHS exposure is becoming available throughout Europe, although unacceptably slowly. The provision of information to people about the health risks of exposure to mould and damp and remedial action is also very poor across the entire Region.[1]

Overall progress

Although infant mortality from respiratory disease has declined throughout the Region, it still contributes substantially to the overall burden of disease, especially in the eastern part of the Region. Chronic respiratory diseases, in the form of asthma and also allergies, are now the most common childhood diseases, and are on the increase.

Both outdoor and indoor air pollution, much of which is anthropogenic, contributes markedly to the incidence and/or prevalence of different respiratory diseases in children in all populations. Lives are substantially shorted by this pollution throughout the Region. Exposure is often linked to socioeconomic status, both at individual level (e.g. damp housing) and at population level (e.g. industrial processes and the intensity and quality of transport in residential areas). Although reductions in pollution have occurred in previous decades in many countries in the Region, further improvement in air quality and reduction of the burden of disease due to air pollution have stalled in the last decade. Such environmental exposure must be reduced through coordinated policy efforts.

In many countries in the Region, especially in the EU countries, reliable and up-to-date information on air quality and health is available. Towards the east of the Region, and in the newly independent states in particular, information is generally poor and also not easily accessible. Highly important information relevant to health, especially regarding the population’s exposure to the inhalable proportions of PM (PM10 and PM2.5), is lacking. This restricts the possibility for proper assessment of the risk from air pollution, the development of effective air pollution reduction strategies, and monitoring of the effects of policy implementation. There has been a shift in the development of outdoor air quality policy from regulation of emissions or compliance with threshold concentrations towards a reduction in exposure of the population. This is mainly the result of WHO’s guidelines followed by international legislation, but requires better monitoring and impact assessments.

Both EU legislation and WHO’s air quality guidelines are important instruments promoting national policy development. The FCTC has become a strong driver for SHS reduction in EU countries and calls for similar action in the rest of the Region. The lack of international legislation or guidelines for damp and mould may be a reason for this field to have been largely “below the radar” for the last decade in EH policies across the Region. The recent launch by WHO of the first indoor air quality guidelines on dampness and mould should, if implemented, have a clear impact on the development of EH policy in Member States.[1]

See also

References

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