- Decrease in Oxygen level or Increase in CO2 level
- Increase in temperature and humidity (Dampness)
- Accumulation of air pollutants
- Increase in bio-aerosol and odor
Indoor air pollution is ranked among the top 5 environmental health risks to the public by Environmental Protection Agency. Carbon-based gaseous pollutants (VOCs) could be 2 – 5 times higher than outdoors. In India, Indoor air pollution is one of the top 10 disease risk factors. It is invisible but no less a threat to our health.
A large part of household items in our homes as well offices are sources of Indoor Air Pollution.
Let us take a quick look at the main sources of indoor air pollution in our homes & offices.
1. Paint and Varnishes and other building materials
Certain paints emit various gases. Toxic Volatile Organic Compounds (VOCs) can be emitted from building material even years after installation. They often cause eye, nose, and throat irritation, nausea, and can also damage the liver, kidney, and central nervous system. Other common symptoms include frequent headaches.
2. Products for household cleaning and maintenance, personal care, or hobbies
Products like Fabric softeners, air fresheners, deodorizers, hair sprays, disinfectants, cleaning products release organic compounds while they are being used and to some extent when they are stored which is very harmful.
3. Extreme temperature and Humidity
Proper temperature is the basic indoor air requirement. Excess moisture in the air leads to the growth of mold, mildew, and fungus, in places like basements and bathrooms. It can trigger allergy, asthma, and conjunctivitis
4. Carpeting and upholstery - wet or damp carpet
Mattresses, upholstered furniture, and carpets are reservoirs for dust mites as dust mites, fungi and bacteria require moisture to proliferate.
5. Non - Stick Cookware
Using non-stick cookware is very common in every home but we are unaware of the fact that overheating of these cookware releases toxic fumes which is not safe for our health.
6. Adhesives in Furniture and Electronics
There are many toxin-releasing furniture which can be found cheaper in the markets but can cost you high medical bills due to their negative health effect.
7. Pet Dander and Hair
The presence of pets in any home does affect indoor air quality. Pets shed their hair and their dander is the significant source of allergy triggers.
8. Carbon dioxide
CO2 released from our lungs is exhaled in the air which pollutes the air if the place is too crowded or there is less ventilation. Where this colorless, odorless gas exists, humans may experience headaches, dizziness, respiratory difficulties, and lethargic conditions.
9. Dusting and Housekeeping activities
We can see the dust floating in the air in front of our window or light. The dust is made up of dust particles, dander, skin cells, and more. We need to use a microfiber cloth or damp cloth for dusting our furniture as they absorb the dust and do not let the dust particle flow in the air.
10. Smoke from Candle, Mosquito Coils, and Incense Sticks
The candles which are made from paraffin wax release toxic chemicals which quickly make the indoor air unhealthy. Mosquito coils release high toxicity insecticide and prolonged use represent a potential threat to children’s health.
11. Pesticides, Disinfectants and Cleaning agents
Pesticides we use in and around the home to kill household pests release various chemical and semi-volatile compounds which leads to indoor air pollution. Chemicals found in various cleaning supplies and disinfectants are very dangerous to our health. The health effects of pesticides vary with the product. However, local effects from most of the products will be on eyes, noses, and throats, more severe consequences, such as on the central nervous system and kidneys and cancer risks, are possible.
12. Kitchen Stove and Cooking Activities
In rural areas, most of the population relies on solid fuels such as dung, wood, crop waste, or coal for cooking. The smoke inhaled is the biggest reason which leads to pneumonia and other respiratory infections. Women and children are heavily exposed to Carbon Mono oxide and other fine particles released during the use of smoky cooking fuels.
13. Second-hand smoke
Second-hand smoke is a mixture of the smoke given off by the burning of tobacco products, such as cigarettes, cigars, or pipes, and the smoke exhaled by smokers. Secondhand smoke is also called environmental tobacco smoke (ETS). Passive smoking can lead to coughing, excess phlegm, and chest discomfort. NCI (National Cancer Institute) also notes that spontaneous abortion (miscarriage), cervical cancer, sudden infant death syndrome, low birth weight, nasal sinus cancer, decreased lung function, exacerbation of cystic fibrosis, and negative cognitive and behavioral effects in children have been linked to ETS. Secondhand smoke exposure commonly occurs indoors, particularly in homes and cars. Secondhand smoke can move between rooms of a home and between apartment units.
14. Central heating and cooling systems and humidification devices
The air filter in your HVAC system is the front line of defense against poor indoor air quality. A typical central heating and cooling system circulate over 1,000 cubic feet per minute of air through the filter. This means the entire air volume in your house passes through the filter multiple times every day. A dirty filter, however, can make indoor air quality worse by acting as a reservoir for dirt, dust, and other airborne contaminants that are continuously circulated back into your breathing air. In addition to driving up your utility bill, a clogged air filter will allow all that dust and debris that should be filtered out to be re-circulated back into your home. This can cause chronic allergies and especially be dangerous for people with asthma or other respiratory conditions.
15. Outdoor sources of pollution
It is generally, a good idea to regularly let in lots of outdoor air to decrease the level of indoor pollutants and toxic gases. The points of entry for outdoor air pollutants are the tiny, often undetectable cracks, openings, and gaps in your walls and windows.
16. Radon
Radon is an odorless, colorless gas that is made naturally when uranium in the earth breaks down. The main source of high-level radon pollution in buildings is surrounding uranium-containing soil. Such gases enter our homes from the cracks. Exposure to Radon can lead to lung cancer/ radon affected DNA condition and sometimes pancreatic cancer.Few other factors also affect indoor air pollution
- How much pollutant is emitted by any single source?
- How hazardous the emissions are for the health of the occupants?
- How old the source is and whether it is properly maintained?
- Whether the environment is properly ventilated?
- Overcrowded Homes
Some health issues like irritation of the eyes, nose, and throat, headaches, dizziness, and fatigue can be due to single-time exposure and they are usually short-term and treatable. Some health issues may show up years after continuous exposure. These issues include respiratory diseases, heart disease, and cancer. Thus we need to have a better understanding of air inside our homes.
Indoor air pollutants
Major indoor pollutants that are present in the aforesaid household items are:- Respirable Suspended Particulate matter (RSPM) or PM (Particulate matter) – Coarse dust particles (PM10) and Fine particles (PM2.5)
- Volatile Organic Compounds (VOCs)
- Carbon dioxide (CO2)
- Formaldehyde (CH2O) gas
- Carbon monoxide (CO)
- Ozone (O3)
- Trichloroethylene
- Benzene
- Nitrogen Dioxide
- Lead (Pb)
- Outdoor Air pollutants
Reference links used:
1. https://www.cpsc.gov/Safety-Education/Safety-Guides/Home/The-Inside-Story-A-Guide-to-Indoor-Air-Quality/
2. https://www.conserve-energy-future.com/causes-and-effects-of-indoor-air-pollution.php
3.www.epa.gov/iaq/voc.html>www.epa.gov/iaq/voc.html”>www.epa.gov/iaq/voc.html
4. https://www.who.int/ceh/capacity/Indoor_Air_Pollution.pdf
5. https://www.cdc.gov/nceh/publications/books/housing/cha05.htm
6. https://chem.libretexts.org/Courses/Sacramento_City_College/SCC%3A_CHEM_330_-_Adventures_in_Chemistry_(Alviar-Agnew)/13%3A_Air/13.08%3A_Indoor_Air_Pollution
7. https://www.centralhtg.com/blog/indoor-air-quality-solutions