Air pollution putting world health at risk

air pollution, climate change, climate crisis, cop27

A herd of cattle feeding besides a burning pile of garbage at Mukuru Kayaba slums, Nairobi on March 22, 2020. The latest data shows that Kenya’s air pollution is 2.9 per cent times higher than the recommended level.

Photo credit: LUCY WANJIRU | NATION MEDIA GROUP

Most of the world’s population is exposed to air pollutants that surpass the World Health Organization’s (WHO) recommended limits, a new study has shown.

A study published in the Lancet’s Planetary Health shows that only 0.001 per cent of the global population is safe from exposure to tiny air particles that are harmful to people’s health.

The researchers analysed data from 175 countries for a period of about two decades.

WHO recommends that particles should be smaller than 2.5 micrometres (PM 2.5) and other pollutants like nitrogen oxide be not more than 10 microgrammes per cubic metre.

Particulate matter in the air comprises sulfates, nitrates, ammonia, sodium chloride, black carbon, mineral dust and water, which enters our bodies through the blood or lungs.

In the analysis, the researchers found that there was an average of 32.8 microgrammes per cubic meter of air (32.8μg/m3), way above the recommended 5μg/m3.

Above guideline levels

Globally, about 70 per cent of days every year were found to have more than the guideline levels of particles smaller than PM2.5.

During the World Health Assembly in 2015, global health leaders adopted a landmark resolution on air quality and health, recognising air pollution as a risk factor for non-communicable diseases like asthma, ischaemic heart disease, stroke, chronic obstructive pulmonary disease and cancer.

Prof Yuming Guo, the lead author of the study, said in a statement that the sub-Saharan region recorded a relatively high PM2.5 between June and September last year.

“The study provides a deep understanding of the current state of outdoor air pollution and its impacts on human health. With this information, policymakers, public health officials and researchers can better assess the short-term and long-term health effects of air pollution and develop air pollution mitigation strategies,” said Prof Guo.

In the country, data from Air Quality in Kenya as of yesterday noon showed that Kajiado, Nakuru and Nairobi counties are the most air polluted in the country. Only two of these were rated “moderate”, the same as the country’s overall profile. Lodwar, in Turkana County, was the safest town in regard to air pollution.

The latest data shows that the country’s air pollution is 2.9 per cent times higher than the recommended level. 

Even so, an estimate from WHO shows that about 19,000 people in the country die due to air pollution. The United Nations Environment Program, in a past study, stated that 70 per cent of pollution in the country is from Nairobi.

Reduce air pollution

At the same time, environmental health researchers from Birmingham University (Suzanne Bartington and Roy Harrison) published an article in the Conversation reacting to the new air quality guidelines by WHO, suggesting what countries need to do to reduce air pollution.

“Regulating air pollution is complex, and measures differ in scope and scale, and what works in one setting may be less effective in another. At a global level, no common framework exists to regulate the most harmful air pollutants beyond those released by shipping and aviation,” they explained.

“Replacing internal combustion engines with electric batteries in much of the country’s vehicles would go a long way towards meeting the NO₂ (nitrogen dioxide) guideline limit. But this will take many years, and it will have little if any, benefit for PM2.5 pollution,” they added.