Why cleaned air?
Air pollutants, in particular, fine particles (commonly referred to as PM2.5) and Volatile Organic Compounds (VOCs), are respirable suspended particulates pollutants, gases phase pollutants, and/or the mixtures of them in the air, and can cause wide ranging adverse effects to human health. Scientific studies have linked exposure to air pollutants to health issues such as impairment to foetus development, child growth, overall wellness, and in severe cases, death. Not only are air pollutants harmful to brain development in children, it also leads to early brain degeneration and the early onset of dementia for the elderlies. Apart from the increased burden towards health care costs, adverse effect of air pollution also create a direct impact on the economic and social development. The overall costs caused by air pollutants continue to rise.
What are the Air Pollutants
Particulates Matter
Particulate Matter (PM), it is a mixture of solid particles and liquid droplets found in the air, including dust, dirt, soot, or smoke and other finer particles, such as: PM10 : inhalable particles, with diameters that are generally 10 micrometers and smaller; and PM2.5 : fine inhalable particles, with diameters that are generally 2.5 micrometers and smaller.
Total Volatile Organic Compounds
Total Volatile Organic Compounds (TVOCs) are organic (carbon-containing) chemicals that are present mostly as gases at room temperature. Some VOCs are odorous and some are suspected causes of adverse health effects. The suspected health effects cover a broad range including, but not limited to, sensory irritation symptoms, allergies and asthma, neurological and liver toxicity, and cancer. While multiple VOCs present together may have effects greater than the sum of their individual effects.
Formaldehyde
Formaldehyde (HCHO) belong to one class of the VOCs, it is widely used in the manufacture of building materials and numerous household products. It has significant health effects and verified to causes the respiratory symptoms, and nasal cancer by the USEPA and WHO, even at very low levels.
Fungi, Airborne Bacteria
Bacteria and fungi will grow, often to an alarming extent, on building materials if moisture is available. Levels of airborne bacteria and fungi change frequently as a result of operation of mechanical air handling systems. Endotoxin, a component of some bacteria, also can cause illnesses among building occupants who inhale this contaminant. Building conditions that allow excessive growth of bacteria or fungi can lead to occupants developing various specific medical symptoms or other complaints.
Virus
Many viruses that infect the respiratory tract spread from person to person, especially in crowded rooms with inadequate ventilation. Coughing, laughing, and sneezing can discharge tens of thousands of virus filled droplets into the air and may readily spread illnesses in schools, offices, homes, or other settings.
Allergen and Dust Mites
Dust mites are microscopic arthropods (a family of related animals) that live indoors and feed on skin flakes and other organic materials in dust. Bedding, upholstered furniture, and carpets are among the sites where dust mites live. The allergens, present primarily within the mite's faecal pellets or their fragments can be inhaled when airborne. Common dust mite allergy symptoms include: Sneezing, Runny nose, Itchy, red or watery eyes, Stuffy nose, itchy nose, mouth or throat, postnasal and cough.Further dust mite allergy may also triggers asthma.
How will PM2.5 affect pregnancy, foetus and infant?
Previous studies have suggested an association between air pollutants and adverse birth outcomes, including low birth weight, pre-term delivery, and infant mortality. Particulate matter is proposed to systemic influences among pregnant women, including effects on placental development or transplacental effects that may result in adverse birth outcomes. Prior analyses indicate that particulate matter PM10 is & PM2.5 associated with pre-term birth. Exposure to high levels of PM10 and PM2.5 were found to reduce intrauterine growth, whereas the PM2.5 appears to be the more potent portion of the particulate matter mixture, resulting in different adverse health risks than those from exposure to PM10 or coarse particles (PM10–PM2.5). It is also found that an increment of 10 mg/m3 of particle concentration (measured as PM10) intake by the infant will associated with to about 5% increase in post-neonatal mortality for all causes and around 22% for post-neonatal mortality for respiratory diseases.
How will PM2.5 affect adults & elders?
For populations of elderly aged 65–99, the EPA estimate nearly 1.1 million life years lost from PM2.5 exposure in the USA. Among the 10 most populous counties, the percentage of deaths attributable to PM2.5 ranges from 3.5% in San Jose to 10% in Los Angeles. These results show that despite significant improvements in air quality in recent decades, levels of PM2.5 pose a nontrivial risk to public health, including the elderly.
It is estimated that approximately 3% of cardiopulmonary and 5% of lung cancer deaths are attributable to PM globally.