Medicine Cabinet -- Reiner Gloor

Air pollution and health

Posted on March 28, 2014

AIR pollution may be a daily reality for many in the country but it is high time to take it more seriously.

Global experts attributed seven million deaths in 2012 to air pollution exposure, making it the world’s largest single environmental health risk.

The World Health Organization (WHO) stepped up calls to reduce air pollution as the number of global deaths due to indoor and outdoor air pollution doubled in 2012.

In its report, the WHO disclosed that both household and ambient air pollution have contributed to the rise in the global burden of major non-communicable diseases such as cardiovascular diseases, cancer, and respiratory diseases.

Indoor and outdoor air pollution deaths have been blamed to ischaemic heart disease; stroke; chronic obstructive pulmonary disease (COPD); lung cancer; and acute lower respiratory infections in children.

As in the case of many other diseases, illnesses associated with air pollution have disproportionately affected people living in low and middle-income countries.

The WHO South-East Asia and Western Pacific Regions, where the Philippines is included, had the largest air pollution-related burden in 2012, with a total of 3.3 million deaths linked to indoor air pollution and 2.6 million deaths related to outdoor air pollution.

In Metro Manila, the Department of Environment and Natural Resources said that air quality data from the Environmental Management Bureau (EMB) indicate that the level of Total Suspended Particulate (TSP) in Metro Manila in 2004 reached 171 micrograms per normal cubic meter (ug/Ncm). It went down to 129 ug/Ncm in 2009, then up again to 150 in 2010. In 2013, TSP level went further down at 118 ug/Ncm but it was still not within the acceptable levels of the Clean Air Act of 1999.

For indoor air pollution, poor women and children pay a heavy price since they spend more time at homes that use coal, wood and biomass stoves for cooking. It was reported that about 2.9 billion people live in homes using wood, crop wastes, coal or dung in open fires and leaky stoves as their primary cooking fuel.

This practice, which is still common in rural communities in the country, produces high levels of household air pollution with a range of health-damaging pollutants. One of these is the small soot particles that penetrate deep into the lungs.

Indoor smoke can be 100 times higher than acceptable levels for small particles in poorly ventilated dwellings. Exposure to household air pollution almost doubles the risk for childhood pneumonia. Over half of deaths among children less than five years old from acute lower respiratory infections (ALRI) are due to particulate matter inhaled from indoor air pollution from household solid fuels, said the WHO.

In the case of outdoor air pollution, WHO estimates there were 3.7 million deaths in 2012 from urban and rural sources worldwide.

Particulate matter (PM) affects more people than any other pollutant. The major components of PM are sulfate, nitrates, ammonia, sodium chloride, black carbon, mineral dust and water. It consists of a complex mixture of solid and liquid particles of organic and inorganic substances suspended in the air, the UN health agency explained.

The most health-damaging particles are those with a diameter of 10 microns or less, which it said could penetrate and lodge deep inside the lungs. Consistent exposure to particles contributes to the risk of developing lung cancer as well as cardiovascular and respiratory diseases.

Apart from PM, exposure to ozone (O3), nitrogen dioxide (NO2) and sulfur dioxide (SO2) can also be dangerous for one’s health. As with PM, concentrations are often highest largely in the urban areas of low- and middle-income countries.

Ozone is a major factor in asthma morbidity and mortality, while nitrogen dioxide and sulfur dioxide also can trigger asthma, bronchial symptoms, lung inflammation and reduced lung function.

The WHO said that ozone at ground levels one of the major constituents of photochemical smog. It is formed by the reaction with sunlight (photochemical reaction) of pollutants such as nitrogen oxides (NOx) from vehicle and industry emissions and volatile organic compounds (VOCs) emitted by vehicles, solvents and industry.

Meanwhile, the major sources of NO2 are combustion processes (heating, power generation, and engines in vehicles and ships).

SO2, on the other hand, is produced from the burning of fossil fuels (coal and oil) and the smelting of mineral ores that contain sulfur. The main source of SO2 is the burning of sulfur-containing fossil fuels for domestic heating, power generation and motor vehicles (Visit www.who.int for more information on air pollutants).

The World Bank warned that the total number of people relying on solid fuels would remain largely unchanged by 2030 if no substantial policy changes were made.

Implementing green policies in transport, urban planning, power generation and industry can help reduce air pollution. However, individual personal commitment and action will also prevent health risks associated with air pollution.

For more information, consult your doctor or you may log on to www.phap.org.ph or www.phapcares.org.ph. Join us on www.facebook.com/people/Pharma-Phap/. E-mail the author at reiner.gloor@gmail.com.