Indoor air pollution: What you can’t see can hurt you

Indoor air pollution causes an estimated 3.2 million premature deaths annually worldwide, primarily due to the use of solid fuels for cooking in developing countries, according to the World Health Organisation (WHO). This largely preventable pollution contributes significantly to respiratory illnesses and other diseases.

In Nigeria, indoor air pollution is widespread, particularly in rural areas. The situation is worsened nationally by the use of generators for domestic electricity production, especially in residential areas, and cooking in enclosed or poorly ventilated spaces. These significantly increase indoor air pollutant concentrations, thus causing severe health issues.

Now, indoor air pollution refers to the contamination of air within buildings and structures and covers a wide range of harmful substances, including gases, particles, and biological contaminants, originating from various sources. Poor ventilation can worsen the issue by preventing the dilution and removal of these pollutants.

When it comes to the primary sources of indoor air pollution, a major distinction is often drawn between developing countries, which frequently rely on biomass for cooking and heating, and industrialised nations, where building materials and household products are more prominent.

Inefficient combustion of solid fuels like wood, charcoal, coal, and crop waste or kerosene in open fires and simple stoves contributes significantly to indoor air pollution. Also, both second-hand smoke from burning tobacco products and chemicals released from them are significant sources of indoor pollutants. In addition, formaldehyde from building materials, paints, and furniture, along with other volatile organic compounds, contributes to poor indoor air quality.

Cleaning products, pesticides, and artificial fragrances equally release harmful chemicals into the indoor environment. Also, biological pollutants, such as animal dander, mould, dust mites, pollen, bacteria, and viruses, are common in indoor environments. Radon, a naturally occurring radioactive gas, can seep into homes from the ground and building materials.

Furthermore, inadequate ventilation, especially in combination with high temperatures and humidity, traps pollutants indoors and leads to higher concentrations. Incense and some mosquito repellents can also release pollutants into the air, while dust, cockroaches, and rodents can similarly act as sources of indoor air pollution.

The truth is that inhaling fine particulate matter, such as soot from burning solid fuels, can cause or worsen respiratory infections, asthma, and chronic obstructive pulmonary disease. Chronic exposure to pollutants from household sources is linked to an increased risk of heart disease and stroke. Household air pollution can cause lung cancer, especially in non-smoking women and people who use solid fuels like wood or coal for heating and cooking. Moreover, maternal exposure to indoor air pollution is associated with low birth weight and preterm births. And household air pollution can contribute to conditions like tuberculosis and cataracts and potentially affect neurological development in children.

Children and the elderly are more susceptible to the health impacts of air pollution. Women and children, however, often bear the greatest burden due to their role in cooking and spending more time indoors, thus increasing their exposure to harmful smoke. People with existing illnesses, especially lung conditions, are also at a higher risk, while low-income households are often excessively affected because they are more likely to use polluting fuels and technologies for cooking and heating.

Now, there are some things you can do to mitigate or prevent household air pollution. You can briefly open windows and doors daily, especially in areas like the kitchen and bathroom, to replace stale indoor air with fresh air from outside. You can also turn on local exhaust fans in kitchens and bathrooms to effectively remove moisture and pollutants generated by cooking and other activities.

It is equally important to reduce pollution at the source by choosing non-toxic products and opting for green cleaners and products with no or low volatile organic compounds, such as paints, finishes, and adhesives. Then avoid smoking indoors, as cigarette smoke contains numerous cancer-causing substances and so should not be smoked inside. And do not burn garbage, as this releases harmful pollutants into the air. When possible, use high-emitting products like paint, glue, incense, and candles outdoors, not indoors.

You can similarly use air purifiers with high-efficiency particulate air (HEPA) filters to remove microscopic particles like dust, pet dander, mould spores, and tobacco smoke. In addition, ensure regular cleaning and drying of indoor spaces to prevent the growth of mould and mildew, particularly in kitchens and bathrooms. Although they are not a primary solution for severe pollution, certain houseplants can help refresh indoor air by metabolising pollutants. And when renovating or building, select “green” building materials, which adhere to environmental and health-friendly principles.

Close your windows and doors to prevent the smoke and fine particles from entering your house if you are dealing with a less immediate threat, such as pollutants like smoke from high outdoor pollution events. You can open the windows to increase ventilation once the outside air quality improves. It is, however, essential to get anyone experiencing symptoms such as headache, dizziness, nausea, shortness of breath, or confusion medical help immediately.

As a general rule, get everyone out of the building and into fresh air if you suspect a serious or widespread problem, such as a gas leak or carbon monoxide exposure, and call for help from appropriate quarters or agencies once you are in a safe location. Do not use lighters, matches, or any electrical device, including appliances, light switches, and phones, since these can create a spark that ignites a flammable gas.

In the end, our well-being is tied, not just to the government or the world outside our windows, but also to the air we breathe within our walls. By having a good knowledge of the sources of indoor air pollution, we can take control of our health and that of those around us. A well-placed air purifier, a commitment to natural cleaning products, and a simple habit of opening windows and doors can make all the difference by transforming our private spaces into true sanctuaries of clean, safe air.

Ojenagbon, a health communication expert and certified management trainer and consultant, lives in Lagos.