Household Pollution: What's Causing It And How To Prevent

Household air pollution is a significant issue that affects the health of millions of people worldwide. It is caused by various indoor sources, including the use of solid fuels such as wood, coal, and kerosene for cooking and heating, tobacco smoke, cleaning products, mould, pet dander, and inadequate ventilation. The release of harmful pollutants, such as fine particulate matter, carbon monoxide, and other toxins, leads to increased health risks, particularly for women and children, who are typically responsible for household chores involving polluting fuels and technologies. Indoor air pollution has been linked to respiratory infections, asthma, heart disease, cancer, and other serious health issues. Addressing household air pollution requires policy changes, improved access to clean fuels and technologies, and increased awareness of the impacts of indoor air quality on human health.

Incomplete combustion of solid fuels

The World Health Organization (WHO) estimates that household air pollution caused by the incomplete combustion of solid fuels leads to approximately 3.2 million premature deaths each year. This includes a significant number of children under the age of five. Women and children, who typically carry out household chores such as cooking and collecting firewood, are disproportionately affected by the health risks associated with indoor air pollution from solid fuel combustion.

The use of solid fuels in poorly ventilated homes can result in high concentrations of pollutants, including particulate matter, gases, and toxic metals such as arsenic and fluorine. These pollutants have been linked to various adverse health outcomes, including respiratory infections, asthma, heart disease, and cancer. Incomplete combustion of solid fuels can also lead to the formation of organic pollutants, such as EPFRs and POPs, which have been detected in indoor air.

The combustion of solid fuels is particularly common in rural areas and low-income communities, where access to clean fuels and technologies may be limited. For example, in Tibet, local biomass fuels such as livestock dung cakes and crop residues constitute more than 54% of energy sources for heating, cooking, and lighting. Similarly, in India, solid fuels like biomass and coal are used as the primary source of energy for cooking and heating, especially in poor rural communities.

To address the issue of indoor air pollution from incomplete combustion of solid fuels, strategies such as providing financial support for cleaner technologies and fuels, improving ventilation and housing design, and raising awareness about the importance of clean energy use are essential. These measures can help reduce the health risks associated with indoor air pollution and improve the overall well-being of those affected.

Tobacco smoke

The smoke from cigarettes, cigars, and pipes is one of the most common and dangerous indoor air pollutants. The air pollution emitted by cigarettes is about 10 times greater than diesel car exhaust. A controlled experiment found that the combined particulate levels in the first hour after lighting a cigarette were 10 times greater than the levels after starting a diesel engine.

Homes that reported cigarette smoking indoors had a median particle level that was close to double that of homes without indoor smoking. These particles contain nicotine and combustion byproducts that are dangerous to people's health, especially children.

Poor ventilation

When there is inadequate ventilation, air pollutants can build up inside a building. Common indoor air pollutants include volatile organic compounds (VOCs), carbon monoxide (CO), carbon dioxide (CO2), fine particulate matter (PM2.5), and secondhand tobacco smoke. These pollutants are produced by various sources, such as cleaning products, smoking, fossil fuels, and even the chemicals used in construction or renovation. For example, glues, off-gassing from carpets, and emissions from particleboard can all contribute to indoor air pollution when ventilation is poor.

In addition to the build-up of pollutants, poor ventilation can also lead to high humidity levels. This is particularly common in cool climates, where normal activities like cooking, bathing, and breathing create moisture, and there is insufficient ventilation to remove it. High humidity can spur the growth of mould, which is a significant indoor air pollutant and health hazard. Mould can cause respiratory infections, asthma, and allergies, especially in individuals with weakened immune systems or pre-existing conditions.

To improve indoor air quality, it is essential to increase ventilation and ensure adequate air circulation. This can be achieved through natural ventilation, such as opening windows, or mechanical ventilation, such as using fans or exhaust systems. In larger buildings, whole-building systems can continuously remove and replace indoor air with filtered and conditioned outdoor air. Additionally, duct sealing and regular maintenance of HVAC systems are important to prevent the spread of contaminants throughout the ventilation system.

It is worth noting that simply increasing ventilation may not always be the solution to indoor air pollution. In areas with poor outdoor air quality, such as near busy highways, ports, or factories, bringing in outdoor air can introduce additional pollutants. Therefore, it is crucial to pair ventilation with source control, such as reducing smoking indoors or using exhaust fans in kitchens and bathrooms to remove pollutants at their source.

Cleaning products

The use of household cleaning products, such as soaps, polishes, and grooming supplies, often introduces harmful chemicals into indoor environments. These chemicals can irritate the eyes, throat, and skin, leading to headaches and other health complications. Some of the chemicals released from these products are linked to respiratory infections, asthma, and even cancer. Additionally, the evaporation of volatile components and rinsing of residual products during cleaning contribute to pollution.

Volatile organic compounds (VOCs) are a significant concern in cleaning products. VOCs are gases that evaporate at room temperature and are released into the air when using cleaning supplies. They contribute to indoor air pollution and have both short-term and long-term health effects. Exposure to VOCs can cause headaches, nausea, and damage to vital organs like the liver, kidneys, and central nervous system. Natural fragrances, such as citrus, can also react to produce dangerous indoor pollutants. It is important to note that even "green" or "natural" products may not be safer, as manufacturers are not required by law to list all ingredients.

To reduce the impact of cleaning products on indoor air quality and personal health, it is advisable to choose products with reduced or no VOCs, fragrances, irritants, and flammable ingredients. Warm water and soap can often effectively clean surfaces, and baking soda is a good alternative for scrubbing. Additionally, the EPA provides a list of products that meet its Safer Choice requirements, offering safer alternatives for cleaning. Proper training and the implementation of a Chemical Management System can also help minimize exposure to concentrated cleaning products for those who regularly perform cleaning tasks.

Overall, cleaning products are a significant contributor to indoor air pollution, and their use can have detrimental effects on human health. It is essential to be mindful of the types of cleaning products used and to prioritize safer alternatives to reduce pollution and health risks.

Construction materials

Building and remodelling materials may emit fumes or dust that can be harmful to human health. Newer construction materials may release fumes or dust, while older building materials can give off indoor air pollutants when disturbed or removed. Plywood, furniture, and other pressed-wood products often contain chemicals that off-gas as the materials age, releasing formaldehyde and other volatile organic compounds (VOCs) into the indoor air. Paints, adhesives, solvents, polishes, carpets, and cleaning products can also emit VOCs, formaldehyde, benzene, and other toxic chemicals over time.

Older buildings constructed before 1978 are likely to contain lead paint, and asbestos may be present in tiles, insulation, or drywall. Disturbing or removing these materials can release hazardous chemicals and dust. "Chinese drywall," installed in buildings along the Gulf Coast states and Virginia between 2001 and 2009, has been found to emit high levels of hydrogen sulfide. Similarly, laminate flooring manufactured in China between 2012 and 2014 has been linked to high formaldehyde emissions.

To reduce indoor air pollution from construction materials, it is recommended to use sustainable and low-emission building materials and paints. Recycling and reusing building materials, opting for low-VOC paints, and improving ventilation and housing design can also help minimize the emission of harmful substances.

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