By Gift Briton

With research showing that air pollution in most Kenyan cities are beyond the threshold, experts warn that long-term exposure to ambient air pollution may cause lung cancer, stroke and heart failure thereby leading to premature death.

Furthermore, World Health Organization (WHO) estimates that in 2019, about seven million premature deaths were attributed annually to the effects of ambient and household air pollution.

According to Prof. Augustine Afullo, Environmental Health consultant at GEOHealth (Global Environmental and Occupational Health) Eastern Africa Hub, polluted air contains fine Particulate Matter(PM)- very tiny solids that can be inhaled and cause serious health problems- adding that other than general allergies like sneezing, coughing, asthma and general discomfort, long-term exposure to these particles is likely to damage both respiratory and cardiovascular systems including inflammation and reddening of breathing system(bronchitis), lung cancer, chronic obstructive pulmonary diseases(COPD), stroke, heart failure and high blood pressure among other complications.

Meanwhile, a research done by International Agency on cancer research in 2013, revealed that outdoor air pollution and particulate matter is carcinogenic to humans and that exposure to these particles is a major cause of cancer.

According to the agency, exposure to fine particulate matter (a major component of air pollution) is projected to become the top environmental cause of premature death globally by 2050- an event which is likely to occur in most developing countries where there is increasing industrialization and urbanization combined with lack of quality air standards.

Prof. Afullo reveals that PM is mainly caused by household combustion, lighting, heating and warming devices, motor vehicles, industrial facilities and forest fires, adding that depending on the diameter, these particles can penetrate into the respiratory system and get deposited on the walls of the system. As a result, long-term deposition of these particles on the sections of the walls of respiratory organs may make them thick and narrow thereby leading to partial blockage overtime.

Consequently, the congestion due to partial blockage may compromise the capacity of these organs to carry out their functions effectively since this could limit their free movement (expansion and contraction of the thoracic muscles and the diaphragm) as required. Also, the air space or capacity (vocal volume or capacity) may be reduced, limiting the amount of air it can hold.

Additionally, Prof. Afullo notes that some of these particles may also get a chance of passing into the blood at the exchange point (in the alveoli where exchange of gases between lungs and blood takes place) and since these particles maybe coated with heavy metals such as lead, chromium and mercury, some of which are carcinogenic, the long-term effect would lead to cancer and death of vital cells, with the cancer causing an inevitable blocking of blood flow to and from the nervous system, leading to stroke.

Prof. Augustine Afullo (right)participating during earth observation regional conference for Africa at RCMRD


In the meantime, a United Nations (UN) study on air quality management capabilities found out that out of 20 cities sampled mainly from developing countries, Nairobi became one of the cities with the lowest ratings on quality air management.

Furthermore, GEOHealth’s (Global Environmental and Occupational Health) Eastern Africa Hub research to assess the burden of diseases caused by environmental and occupational exposures in six hospitals in Nairobi city revealed that the burden of diseases associated with respiratory and cardiovascular is growing very fast.

In addition, the organization’s measurement of the level of fine particulate matter in the central site of Nairobi showed that the city has the highest concentration of fine particulate matter between 6-8pm and 6-8am whereas the city was recorded to be cleanest between 1-3am.

To assess the effect of ambient and indoor air quality on child pulmonary function in Nairobi, the organization carried out a lung function test among children between 9 and 12-year-old across ten schools evenly distributed in Nairobi county.

During the exercise, children were asked to breathe in forcefully to lung capacity then breath out very fast, as much as possible, with one second. The machine then measures the amount of air breathed in and out within a second to confirm if the lung is properly functioning.  The lung function is calculated by getting the amount of forced expiratory volume (FEV1, amount of air forced out within one second) divided by vocal capacity (VC, the amount of air forced in-estimated to be the lung capacity).

According to Prof. Afullo, normally, any percentage between 75-80 is an indication of good functioning lung, however, any percentage between 70-75 is an indication that there is minimal blockage or there is something developing in the system, while anything under 70 percent is a clear evidence that there is a blockage in the breathing system.

The organization also measured the concentration of fine particulate matter in the same schools and the results revealed that schools closer to industries and along busy road and highways, for instance those within the central business district, had the highest number of children with low lung function.

Accordingly, the closer a school is to an industrial area and very busy road, the higher the fine particulate matter concentration whereas the closer a school is to leafy suburb the lower the fine particulate matter concentration. For instance, Karen C school which is located in Karen had the lowest concentration of fine particulate while schools located closer to Nairobi central business district such as Moi Avenue primary school had the highest concentration of fine particulate matter. According to the research, five out of a hundred children living or studying within industrial areas, Nairobi CBD or dumpsite environs have a challenge of lung function.

Mix of outdoor and indoor air pollution photo credits: WHO

In this regard, Prof Afullo recommends that the government and policy makers can use this data for urban planning so as to avoid building schools around those pollution prone areas because it causes lung damage among children.

He also urged the Ministry of Health to start integrating preventive healthcare into its public health and environmental health programs, noting that healthcare in Kenya has been largely curative in nature which largely entails dealing with symptoms and crisis as opposed to being preventive. To this end, Prof Afullo proposes the adoption of a 24-hour economy system to help reduce extremes of air pollution in that it could help reduce congestion of people and vehicles (major contributors of air pollution) in the city during the day and other peak others.

According to WHO, though some countries have air quality standards, most of the national air quality are not aligned with the organization’s air quality guidelines. Therefore, the organization has urged countries to develop standards for air quality values as per WHO guidelines.  To attain clean air in cities, the health organization note that existing resources should be aligned to help countries develop and implement air quality management systems. At local, national and regional levels( in East Africa), careful setting and enforcement of emission standards, coupled with strict licensing of potentially polluting equipment and processes should be ensured.