The air in our atmosphere is composed of about 78% nitrogen, 21% oxygen, and 0.93% argon. The remainder, less than 0.1%, contains many small but important trace gases, including water vapor, carbon dioxide, and ozone. All of these trace gases have important effects on the earth's climate.

Urbanization and industrialization are the major causes of air pollution problem in Kenya .With a population of about 3.36 million living in the Capital City Nairobi, emissions from motor vehicle traffic is an important source of particulate pollution  .It is estimated that the concentration of particulate matter is significantly high and exceed the World Health Organization (WHO) 24 hours guidelines of 150 – 230 grams per cubic meters for ambient air.Research has shown that lack of effective transport and land use planning is resulting in increasing vehicle ownership and traffic congestion. These factors combine to create air pollution hotspots near roads.A (UN, 2010) reports that Urban growth is expected to continue at a rapid pace in the developing world, particularly in sub-Saharan Africa as rural populations continue to migrate to cities in search of employment and expectations of better living conditions.

Large concentrations of air pollution are evident across industrialized areas in Kenya, For example at Webuye Paper and Pulp factory trees have turned yellow due to emitted sulfur compounds into the air .Many case studies have documented that air pollution can be harmful even when it's not visible,some pollutants can harm public health and welfare even at low levels .

Urban outdoor air pollution is estimated to cause 1.3 million deaths worldwide per year .Children are particularly at risk due to the immaturity of their respiratory organ systems. Exposure to air pollutants is largely beyond the control of individuals and requires action by public authorities at the national, regional and even international levels.

Energy poverty has also led to emergence of Indoor air pollution challenges in Kenya with approximately 2 million deaths reported annually. Burning of biomass fuels in the form of wood, dung and crop residue .result to high levels of indoor air pollution, to which women, especially those responsible for cooking, and their young children, are most heavily exposed to causing acute lower respiratory infections, in particular pneumonia, among young children.

Air pollution endangers the health and welfare of current and future generations by causing climate change challenges .Global discussions on climate change under UNFCCC have put a lot of emphasis on reduction of greenhouse gas emissions.

From research I noted that Kenya has taken several steps to address air pollution including

1. Removal of Lead in petroleum to reduce pollution from combustion engines including vehicles.

2. Prohibition of air pollution by the Environmental Management and Coordination Act (1999).

3. Gazettement of air quality regulations (2014)

4. Prohibition of importation of used vehicles older than 8 years to reduce vehicular air pollution.

5. Annual environmental audits requirements by EIA/EA regulations (2003) makes regulated facilities to declare their emissions and corrective action enforced.

6.Promotion of affordable clean cooking stoves among rural areas in Kenya , Public Awareness of indoor air pollution

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