dd3-e355ab46eae0b32a.pdf

The 2005 WHO Global update on air quality guidelines provides health-based recommendations for particulate matter (PM), ozone (O3), nitrogen dioxide (NO2), and sulfur dioxide (SO2). Key revisions include lowering the ozone guideline to 100 ug/m3 (8-hour mean) and the sulfur dioxide 24-hour guideline to 20 ug/m3. The guidelines for NO2 remained unchanged. The document emphasizes that no safe threshold exists for many pollutants, meaning guidelines aim to reduce risk rather than eliminate it entirely. It also introduces interim targets to help highly polluted areas progressively reduce concentrations.

• The WHO established revised air quality guidelines for particulate matter (PM), specifying an annual mean of 10 ug/m3 and a 24-hour mean of 25 ug/m3 for PM2.5. For PM10, the guidelines are 20 ug/m3 (annual mean) and 50 ug/m3 (24-hour mean). The document notes that there is "little evidence to suggest a threshold below which no adverse health effects would be anticipated," meaning these guidelines cannot fully protect every individual.
• The WHO introduced interim targets (IT) for pollutants to provide incremental steps for areas with high pollution levels. For PM2.5 annual means, these targets are IT-1 (35 ug/m3), IT-2 (25 ug/m3), and IT-3 (15 ug/m3). Attaining the IT-2 value is estimated to reduce long-term exposure health risks by approximately 6% relative to the IT-1 value.
• The document highlights that air pollution causes more than 2 million premature deaths annually, with more than half of this burden occurring in developing countries. It notes that the health risks of short-term exposure to PM2.5 are similar across developed and developing countries, with an estimated mortality increase of around 0.5% for each 10 ug/m3 increment in daily concentration.

APA

Centre for Environmental Rights (n.d.). dd3-e355ab46eae0b32a.pdf. https://cer.org.za/wp-content/uploads/2015/04/DD3.pdf?x21779

Chicago

Centre for Environmental Rights. dd3-e355ab46eae0b32a.pdf. n.d. https://cer.org.za/wp-content/uploads/2015/04/DD3.pdf?x21779.

Wikipedia

{{cite report |author=Centre for Environmental Rights |title=dd3-e355ab46eae0b32a.pdf |url=https://cer.org.za/wp-content/uploads/2015/04/DD3.pdf?x21779 |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{centreforenvironmentalrightsnddd3e355ab46eae0b32apdf, author = {{Centre for Environmental Rights}}, title = {{dd3-e355ab46eae0b32a.pdf}}, institution = {Centre for Environmental Rights}, url = {https://cer.org.za/wp-content/uploads/2015/04/DD3.pdf?x21779}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }