7. Environmental Quality
Environmental Quality is about environmental hazards and amenities – illustrated here by air quality and access to green space. Nearly two-thirds of people in OECD countries are exposed to dangerous levels of fine particulate matter (PM2.5) air pollution. Although levels have generally improved since 2005, this has not always occurred where the situation was most critical: in one-quarter of OECD countries, all (or almost all) of the population remains exposed to dangerous levels of PM2.5. Differences within countries can be as large as differences between countries: dangerous levels of PM2.5 exposure can concern less than 1% of the population in one region, while affecting 100% in another. Almost 7% of people living in European cities lack access to green areas in their neighbourhood; comparable data for other OECD countries still need to be developed.
Note: The snapshot depicts data for 2017, or the latest available year, for each indicator. The colour of the circle indicates the direction of change, relative to 2010, or the closest available year: improvement is shown in blue, deterioration in orange, and no clear or consistent change in grey, and insufficient time series to determine trends in white. For each indicator, the OECD country with the lowest (on the left) and highest (on the right) well-being level are labelled, along with the OECD average. For full details of the methodology, see the Reader’s Guide. For access to green space, urban areas refer to cities with 50 000 inhabitants or more: This means that data for Iceland refer only to the capital.
Source: OECD Exposure to PM2.5 in countries and regions (database), http://dotstat.oecd.org/Index.aspx?DataSetCode=EXP_PM2_5 and (Poelman, 2018[1]), “A walk to the park? Assessing access to green areas in Europe’s cities, update using completed Copernicus urban atlas data”, European Commission, Regional and urban policy, https://ec.europa.eu/regional_policy/sources/docgener/work/2018_01_green_urban_area.pdf.
Fine particulate matter (PM2.5) is an air pollutant that can be inhaled and cause serious health problems, including both respiratory and cardiovascular diseases. Nearly two-thirds of the population across OECD countries (63%) are exposed to levels of PM2.5 air pollution above the WHO threshold level (10 micrograms per cubic metre) thought to be dangerous to human health (Figure 7.2). In Canada, Estonia, Finland and New Zealand, fewer than 1% of people have an average annual exposure above the threshold level, while in the Czech Republic, Greece, Hungary, Israel, Korea, Mexico, the Netherlands, Poland, the Slovak Republic and Slovenia all (or almost all) of the population are exposed to dangerous levels of air pollution. Among OECD Partner countries, the same is true also for Costa Rica and South Africa.
Between 2005 and 2017, the share of the population exposed to PM2.5 above 10 micrograms/m3 fell by 12 percentage points on average across OECD countries (Figure 7.2). The largest improvements occurred in Ireland, the United States, Portugal and Switzerland, where the share fell by 40 percentage points or more. There were no improvements in the Czech Republic, Greece, Hungary, Israel, Korea, Mexico, the Netherlands, Poland, the Slovak Republic or Slovenia, where all (or almost all) the population remain exposed to PM2.5 above 10 micrograms/m3. This is again also the case for Costa Rica and South Africa.
Different threshold measures can be used to look at air pollution of different levels of severity (Figure 7.3). These reveal a more nuanced picture than a single threshold. For example, some countries with very high exposure rates at 10 and 15 micrograms/m3 (e.g. Hungary, Slovenia and the Slovak Republic) have almost no one exposed at the more severe 20 micrograms/m3 threshold. By contrast, in Chile and Korea, more than 40% of the population are exposed even at the more severe threshold level.
Note: The OECD average excludes Turkey, as data are not available. For this indicator only, 2005 is used as the reference point for change over time instead of 2010, because the heterogeneous geographical and temporal coverage of available ground monitoring station and satellite observations are insufficient to reliably resolve shorter-term local trends. See (Shaddick et al., 2018[2]) for more information on the concentration estimation methodology.
Source: OECD Exposure to PM2.5 in countries and regions (database), http://dotstat.oecd.org/Index.aspx?DataSetCode=EXP_PM2_5.
Note: Countries are subsequently ranked by the share of the population exposed to PM2.5 above 20 micrograms/m3, above 15 micrograms/m3 and above 10 micrograms/m3. The OECD average excludes Turkey, as data are not available.
Source: OECD Exposure to PM2.5 in countries and regions (database), http://dotstat.oecd.org/Index.aspx?DataSetCode=EXP_PM2_5.
On average in European urban areas, 93% of people have access to public parks, forests or other recreational green spaces within 10 minutes’ walking distance from their home (Figure 7.4). In Austria, Finland, Luxembourg and Sweden, this share exceeds 98% of the urban population, while in Iceland it is only two-thirds.
Note: Green space refers to green areas with a minimum mapping unit of 0.25 hectares. They are predominantly areas for recreational use such as gardens, zoos, parks, castle parks, and suburban natural areas that have become and are managed as urban parks. Forests at the fringe of cities are also included. Urban areas are defined as (greater) cities with an urban centre of at least 50 000 inhabitants, meaning that data for Iceland refers to the capital city only, where many green areas do not meet the definition of recreational use applied in this methodology. The OECD average excludes Australia, Canada, Chile, Colombia, Israel, Japan, Korea, Mexico, New Zealand, Turkey and the United States, as data are not available.
Source: (Poelman, 2018[1]), “A walk to the park? Assessing access to green areas in Europe’s cities, update using completed Copernicus urban atlas data”, European Commission, Regional and urban policy, https://ec.europa.eu/regional_policy/sources/docgener/work/2018_01_green_urban_area.pdf.
It remains challenging to measure horizontal inequalities, such as differences between men and women, by age and by education, in relation to Environmental Quality. However, information on exposure to air pollution is available at the regional (subnational) level, revealing stark differences within countries. For example, in Australia, Chile, Denmark, Iceland, Japan, Spain and Switzerland, the least polluted region has fewer than 1% of the population exposed to dangerous levels of PM2.5, while the most polluted region has 100% of the population exposed. Among OECD partner countries, this is also the case for Brazil and the Russian Federation (Figure 7.5).
Note: The OECD average excludes Turkey, as data are not available.
Source: OECD Exposure to PM2.5 in countries and regions (database), http://dotstat.oecd.org/Index.aspx?DataSetCode=EXP_PM2_5.
Environmental Quality affects human health through the quality of air, water and soil, which is related to the presence and density of hazardous substances. Environmental Quality also matters intrinsically to people who value natural beauty and the amenities that affect their life choices (e.g. a place to live) (Balestra and Dottori. Davide, 2012[3]). Finally, people benefit from environmental services and assets. For example, access to green space is associated with numerous health and well-being benefits, including psychological relaxation, stress reduction, enhanced physical activity, the mitigation of exposure to air pollution, excessive heat and noise, improved social capital and pro-environmental behaviours (WHO Regional Office for Europe, 2016[4]) (Engemann et al., 2019[5]). The indicators included in this chapter (Table 7.1) are complemented by a broader range of Natural Capital indicators in Reference Chapter 14.
Exposure to outdoor air pollution refers to the share of the population living in areas with annual concentrations of fine particulate matter less than 2.5 microns in diameter (known as PM2.5) exceeding the WHO Air Quality Guideline value of 10 micrograms per cubic metre (WHO, 2006[6]). Fine particulate matter is an air pollutant that can be inhaled and cause serious health problems, including both respiratory and cardiovascular disease, having its most severe effects on children and elderly people. The PM2.5 concentration estimates shown here are taken from the Global Burden of Disease 2017 project. They are derived by integrating satellite observations, chemical transport models and measurements from ground monitoring station networks. The concentration estimates are population-weighted using gridded population datasets from the EU Joint Research Center’s Global Human Settlement project. These are produced by distributing census-derived population estimates from the Gridded Population of the World, version 4 from the NASA Socioeconomic Data and Applications Center, according to the density and distribution of built-up areas. The underlying boundary geometries are taken from the Global Administrative Unit Layers developed by the UN FAO, and the OECD Territorial Classification, when available. The accuracy of these exposure estimates varies considerably by location. Accuracy is generally good in regions with dense networks of monitoring stations (such as most advanced economies), while it is particularly poor in areas with few monitoring stations and in areas with very high population concentrations, such as Africa, the Middle East and South Asia (Shaddick et al., 2018[2]). For some regions, particularly snow-covered areas, small islands and coastal areas, there are no PM2.5 concentration estimates for part of the region because satellite-based aerosol optical depth measurements are not reliable in areas where the dominant land cover is very reflective (Mackie, Haščič and Cárdenas Rodríguez, 2016[7]).
Access to recreational green space in urban areas refers to the share of the urban population who lack access to recreational green space within 10 minutes’ walking distance from their home. Urban areas are defined as (greater) cities with an urban centre of at least 50 000 inhabitants (Dijkstra and Poelman, 2012[8]). Green space refers to green areas with a minimum mapping unit of 0.25 hectares. They are predominantly areas for recreational use such as gardens, zoos, parks, castle parks, and suburban natural areas that have become and are managed as urban parks. Forests at the fringe of cities are also included. The underlying method consists of determining an area of easy walking distance – around 10 minutes’ walking time (with an average speed of 5 km per hour) – around an inhabited Urban Atlas polygon. Data have been calculated by Poelman (Poelman, 2018[1]; Poelman, 2016[9]), using the European (Copernicus) Urban Atlas polygons (i.e. satellite data).
There is currently no universally accepted definition of green space. However, with regard to its impacts on people’s health and well-being, the WHO Regional Office for Europe recommends a proximity-based indicator of green space accessibility, based on the European Urban Atlas, as the most appropriate and feasible international source of urban green space data in the EU (WHO Regional Office for Europe, 2016[4]). This indicator is not currently scheduled for regular updates.
Correlations among indicators of Environmental Quality
There is no correlation between air pollution and access to green space for the 26 OECD countries with data on both (Table 7.2). This implies that each indicator discussed in this chapter captures a different facet of Environmental Quality.
Statistical agenda ahead
An ideal set of indicators of Environmental Quality would inform on the impact of environmental hazards on human health, on people’s access to environmental services and amenities, and on people’s own feelings and evaluations of their environmental conditions and amenities. However, currently, internationally comparable information is limited. The How’s Life? measurement set could be further strengthened by defining and developing internationally harmonised data in relation to:
Indicators on people’s access to environmental services and amenities – particularly on water quality and recreational green space (the latter is currently available only for urban centres in European OECD countries and can be considered a “placeholder” until better data are available).
Indicators that reflect people’s own feelings and evaluations of their environmental conditions and amenities. Environmental Quality is valued by people, who attach importance to natural beauty and the healthiness of their environment (Balestra and Dottori. Davide, 2012[3]). Perceptions of environmental amenities (and disamenities) also affect the choices that people make, such as when choosing a place to live (Stiglitz, Sen and Fitoussi, 2009[10]).
Horizontal inequalities beyond regional and other spatial inequalities (for example, by gender, age and education). The evidence is currently patchy. In 2018, the OECD Environment Directorate launched “The Geography of Well-Being”, a project aimed at building a comprehensive database of exposure to environmental risks disaggregated by socioeconomic status, using metrics that are harmonised across countries and which can be considered a first step in this direction.
Damage from environmental disasters, which has been conceptually associated with Environmental Quality (Stiglitz, Sen and Fitoussi, 2009[10]).
Information on mortality and morbidity (i.e. Disability-Adjusted Life Years (DALY)) from exposure to a selection of environmental risks (air pollution, lead, residential radon, unsafe water, sanitation, handwashing) is available, and could be considered for inclusion in the future.
References
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[8] Dijkstra, L. and H. Poelman (2012), “Cities in Europe, the new OECD-EC definition”, Regional and Urban Policy, European Commission, https://ec.europa.eu/regional_policy/sources/docgener/focus/2012_01_city.pdf (accessed on 9 September 2019).
[5] Engemann, K. et al. (2019), “Residential green space in childhood is associated with lower risk of psychiatric disorders from adolescence into adulthood”, Proceedings of the National Academy of Sciences of the United States of America, Vol. 116/11, pp. 5188-5193, https://doi.org/10.1073/pnas.1807504116.
[7] Mackie, A., I. Haščič and M. Cárdenas Rodríguez (2016), “Population Exposure to Fine Particles: Methodology and Results for OECD and G20 Countries”, OECD Green Growth Papers, No. 2016/02, OECD, Paris, http://oecd.org/greengrowth (accessed on 18 July 2019).
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[2] Shaddick, G. et al. (2018), “Data Integration for the Assessment of Population Exposure to Ambient Air Pollution for Global Burden of Disease Assessment”, Environmental Science & Technology, Vol. 52/16, pp. 9069-9078, https://doi.org/10.1021/acs.est.8b02864.
[10] Stiglitz, J., A. Sen and J. Fitoussi (2009), Report by the Commission on the Measurement of Economic Performance and Social Progress, http://stiglitz-sen-fitoussi.fr (accessed on 18 July 2019).
[6] WHO (2006), WHO Air quality guidelines for particulate matter, ozone, nitrogen dioxide and sulfur dioxide, https://apps.who.int/iris/bitstream/handle/10665/69477/WHO_SDE_PHE_OEH_06.02_eng.pdf?sequence=1 (accessed on 18 July 2019).
[4] WHO Regional Office for Europe (2016), Urban green spaces and health, http://euro.who.int/__data/assets/pdf_file/0005/321971/Urban-green-spaces-and-health-review-evidence.pdf?ua=1 (accessed on 18 July 2019).