City dwellers' health in peril: Revealing the devastating effects of air pollution and non-communicable diseases

Bangladesh is one of the most polluted countries in the world, with nine out of ten people living in places where air quality exceeds World Health Organization (WHO) guidelines.  This alarming level of air pollution poses a significant risk for the prevalence of non-communicable diseases (NCDs), including cardiovascular disease, respiratory disease, cancer, and diabetes, which collectively contribute to around 70% of the total mortality rate in the country.  

According to a report published by World Bank, air pollution in Bangladesh is responsible for around 20% of premature deaths and this significant impact on public health translates into a substantial economic cost, estimated to be approximately 3.9% to 4.4% of the country's GDP.   

Air pollution in urban areas primarily originates from two sources: industrial smoke and vehicle emissions. Additionally, brick kilns, fertiliser factories, and road construction activities contribute to air pollution as well. These sources release significant amounts of smoke, vapor, gases, and dust particles that blend with the air, resulting in air pollution.  

Tanneries continuously discharge chemicals such as hydrogen sulfide, ammonia, chlorine, and various other substances. The rise of urbanization has led to an increase in the number of vehicles in cities, further exacerbating air pollution. Aging buses and trucks equipped with weak engines traverse the city streets, emitting black smoke and toxic gases. In fact, a considerable number of vehicles operating on city's roads daily are faulty and emit smoke levels that exceed acceptable limits. Diesel vehicles emit black smoke, which consists of fine carbon particles resulting from incomplete combustion.     

WHO has identified six major factors that have detrimental effects on public health.  These factors include fine particulate matter (PM2.5), heavy particulate matter (PM10), ground-level ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO).  Among these, PM2.5 poses the greatest harm to human health. Due to their tiny size, these pollutants have the ability to enter the body through the nose, infiltrate the bloodstream via the lungs, and potentially impact major organs.  Exposure to PM2.5 leads to short-term and long-term exacerbation of health issues, such as heart disease and various respiratory diseases such as asthma, bronchitis, and lung cancer.      

According to a study conducted by WB, urban areas experience high concentrations of PM2.5 during the dry season.  This is primarily due to extensive construction work and continuous traffic congestion. The recorded levels were found to be nearly 150 percent higher than the air quality guidelines set by WHO, equivalent to smoking 1.7 cigarettes per day.  The second highest concentration of PM2.5 levels was observed near a brick kiln, which exceeded the World Health Organization guidelines by 136 percent, or the equivalent of smoking 1.6 cigarettes per day.  Research conducted by World Bank indicates that even a mere 1 percent increase in PM2.5 levels, as per WHO's Air Quality Guidelines for 2021, raises the risk of experiencing shortness of breath by 12.8 percent, coughing by 12.5 percent, and respiratory tract infections by 8.1 percent. 

The impact of air pollution on human health is wide-ranging and can affect individuals of all ages. Individuals most vulnerable to the effects of air pollution include those aged 65 and above, children between the ages of zero and five, and individuals undergoing medical treatment for other illnesses.    

Short-term exposure to high levels of air pollution can lead to respiratory issues such as asthma, bronchitis, and pneumonia.

Additionally, it can cause eye irritation, coughing, and breathing difficulties. Prolonged exposure to polluted air has been linked to the development of chronic respiratory diseases like chronic obstructive pulmonary disease (COPD) and lung cancer.    Moreover, air pollution has been recognized as a significant risk factor for NCDs in urban areas of Bangladesh.  NCDs, such as cardio-vascular diseases, diabetes, stroke, cancer, chronic obstructive pulmonary disease (COPD), asthma, bronchitis, pneumonia, mental health, injury etc diseases are a major cause of morbidity and mortality worldwide.  According to a study, exposure to air pollution increases the risk of stroke, heart attack, and other cardiovascular conditions. issues such as asthma, bronchitis, and pneumonia. Additionally, it can cause eye irritation, coughing, and breathing. 

However, it requires multi-sectoral and multi-level actions from governments, industries, communities, and individuals to address this complex challenge. Some of the possible solutions to reduce air pollution include implementing stricter emission standards and regulations for vehicles, industries, power plants, and brick kilns.    

Another solution could be promoting clean energy sources and technologies, such as renewable energy, energy efficiency, and electric vehicles. Improving public transportation systems and encouraging active modes of transport, such as walking, cycling, and carpooling, can also contribute to reducing air pollution.  

Enhancing urban planning and green spaces to reduce traffic congestion and improve air quality is crucial. Raising public awareness and education about the causes and effects of air pollution and how to protect oneself and others from exposure is another important aspect. Encouraging the use of masks and air purifiers can also provide some protection to individuals in highly polluted areas.   

Lastly, supporting research and innovation to develop new methods and tools to monitor, assess, and mitigate air pollution is essential.

Dr Md Shamim Haider Talukdar is the CEO, Eminence Associates for Social Development, and consultant at Unicef

Shuhail Hussain is a research assistant, Eminence Associates for Social Development