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Health effects

Other long-term health impacts that are not related to respiratory and cardiovascular function include: an increased risk of cancer from exposure to various particles; and effects on the development of children from exposure to lead. For a more detailed description of the pollutants and their health effects, see Quick links to pollutants.

For more info on air pollution and health >> www.euro.who.int

Factors that influence health impacts: Health impacts vary with the intensity and the duration of exposure, and with the health status of the exposed person. Certain members of the population (such as the elderly, children, and those already suffering from respiratory and cardiovascular diseases) are at greater risk.

Health impacts also vary depending on the location of emissions. Pollutants emitted in cities will affect more people, compared with emissions in rural areas. Climatic conditions – such as wind – affect the duration of time that pollutants remain airborne and therefore can be inhaled. Geographic conditions – such as altitude and proximity to mountains or oceans – also affect the formation of  pollutants, such as ground-level ozone see e.g. Los Angeles and Athens. The figure above indicates the varying costs of damage based on location.

Air Quality Guidelines

Air quality guidelines: The World Health Organisation (WHO) has established guidelines for air quality (See table below). The concentrations set out by the WHO are at levels to preclude any measurable effects on human health.

Despite these standards, in the EU nearly half of all citizens are exposed to air pollution levels that exceed the air quality standards set to protect human health. Air quality standards are frequently exceeded in Japan and in the US as well. Many developing countries lack national air quality standards and monitoring, and it is assumed that the WHO-recommended air quality standards are frequently exceeded in cities. The WHO estimates that over one billion people breathe air that exceeds WHO guidelines on air quality.

Air Quality Guidelines

A. No guideline values were set for particulate matter because there is no evident threshold for effects on morbidity and mortality. In the EU, an average 24 hours level of 50 mg/m3 is recommended.
B. The guideline is to prevent carboxyhemoglobin levels in the blood from exceeding 2.5%, The values above are mathematical estimates of some of the CO concentrations and averaging times at which this goal should be achieved.
C. The guideline for lead was established by the WHO in 1987.
D. Concentrations of pollutants in the air are measured as an average over a predefined time, thus the different values in the above table

Source: Update and revision of the air quality guidelines for Europe