Evidence is mounting that much lower air pollution levels than previously thought can cause harm to health. This threat may potentially be further exacerbated by climate change.
Temperature and air pollution are highly correlated, and can have a synergetic impact on human health. Health effects of particulate matter (PM) air pollution are a leading environmental health concern worldwide according to the World Health Organization (WHO). This is especially important in the GCC, where natural dust can cause high levels of PM pollution in both rural and urban areas. The modeled data for air pollution levels show that the annually averaged PM surface concentrations in the Middle East’s major cities are very high. The main sources of anthropogenic sulfate aerosols were found to be industrial, traffic, and household emissions, which contribute significantly to air pollution, especially on the west and east coasts of Saudi Arabia and over the Arabian Gulf. This highlights an opportunity to impose stricter requirements on anthropogenic pollution.
The last update of air quality guidelines by the WHO was in 2005, recommending upper threshold values for fine particulate matter with an aerodynamic diameter smaller than 10 5m and 2.5 5m (PM10 and PM2.5), ozone (O3), nitrogen dioxide (NO2) and sulfur dioxide (SO2). Some countries have adopted the guideline for annual mean NO2 of 40 5g/m3, and a few countries that for PM2.5 of 10 5g/m3, whereas many countries have defined higher threshold levels or do not manage air quality at all.