Due to modernization, industrialization and migration people spend almost 90% of their time indoor, which enhancing indoor human activity, lower gas exchange and infiltration of outdoor air that ultimately enhances concentration of indoor pollutants
Humans are interacting with their environment since the dawn of civilization but human-environment interaction started to become worse before 700,000 years ago, when our ancestors understood the use of plant wood as fire to make their life comfortable. Human society as a whole depends on the environment to obtain their resources like food, wood, clean water, fiber natural gas etc. and to achieve such resources in an efficient way; humans are continuously modifying their environment.
Now a day environment is prime concern of all human communities throughout the world due to enhancing pollution (any unwanted change in physical, chemical and biological properties of environment due to different pollutants). Currently air pollution is one of the common and biggest menaces for survival of all living things in this world because air is basic necessity for healthy living.
As normally one adult takes 30 lb (pound) of healthy air every day and he cannot live for five minutes without it but can live for 5 days without water and 5 weeks without food. In big cities of world well developed countries, 20-200 people died every day due to air pollutants and in developing countries 10-15% people are suffered from common diseases like cold, bronchitis, asthma etc caused by air pollutants.
Whenever we talk about air pollutants the things strike in our mind are vehicles, exhaust, volcanic eruption, forest fire, burning etc, which cause outdoor air pollution but now together with that our big concern is indoor air which is 12% more polluted than outdoor air.
Now due to modernization, industrialization and migration people spend almost 90% of their time indoor, which enhancing indoor human activity, lower gas exchange and infiltration of outdoor air that ultimately enhances concentration of indoor pollutants like carbon monoxide, nitrogen oxide (NO), Sulphur dioxide (SO2), arsenic (As), fluorine (F), volatile organic compounds (VOC), ozone (O3), radon (Rn), hydrocarbon, lead (Pb), aldehyde.
Such pollutants are causing variety of acute and chronic diseases (pulmonary, neurological, developmental, reproductive, cardiac, even cancer), which are very severe in developing countries due to poor ventilation and higher use of wood, charcoal, and animal dung during cooking and heating.
Indoor air pollutants causes 3 million deaths annually along with some unknown health problems due to sick building syndrome (condition in which people living in building feel illness or uncomfortable without any apparent reason).
Following are different methods used to control indoor air pollution
- HEPA (High Efficiency Particulate Air) filter: It a type of highly efficient air filters that helps in grasping dust particles, including chemical and biological allergen from indoor air of homes, medical facilities, automobiles and aircraft.
- Mopping: Mopping is common and old method to remove the settles dust from floor of room. It should be regularly used to spiff up indoor floor.
- Ventilation: Proper ventilation with exhaust fans, door, window and sunlight exposure is efficiently used to remove the odor, germs and polluted air.
- Ban on smoking: Smoking should be forbidden under indoor conditions because it is a source of carbon monoxide, particulate matter and volatile organic compounds, which are equally effective for smoker and other nearby people.
- Beeswax candles: Beeswax candles are natural air purifiers that burn slowly and helpful to reduce indoor air pollution. It produces ion that combine with other free ions to make them heavier and neutralizing their toxic effects,
- Salt lamps: Salt lamps also improve air purification by attracting water molecules along with dust particle from the air. When lamp is lit up water evaporates in air leaving behind dust.
- Carbon filters: It is also a method of filtration that contains activated carbon, which absorbs contamination and purifies air passes through it.
- Use a Doormat: Doormat should be used to reduce pollution carried by shoes.
- Minimum carpet use: Carpet is best place to trap dust, mites and spores so their use should be minimum under indoor conditions.
- Phytoremediation: It is an attractive, natural, low cost and multipurpose way to control indoor air pollutants through biological, chemical and physical activities of plants. Indoor plants along with removing indoor air pollution, also enhances the comfort, memory retention, mental functioning, reduction of pain perception during work under indoor conditions.
Variety of indoor plant can be used to control indoor pollutants and different characteristics of plant like leaf size and structure, leaf thickness, pubescence and roughness of leaf surface contributed for better absorption of pollutants.
Following are the indoor plants used to absorb different air pollutants.
Boston fern (Nephrolepis exaltata) absorbs toluene, xylene and formaldehyde; English ivy (Hedera helix) absorbs toluene, xylene, formaldehyde, ammonia and hydrocarbon; Spider plant (Chlorophytum comosum) absorbs ozone, toluene, xylene, formaldehyde and hydrocarbon; Money plant (Epipremnum aureum) absorbs benzene, toluene, xylene, formaldehyde; Peace lily (Spathiphyllum wallisii) absorbs benzene, toluene, xylene, formaldehyde, trichloroethylene, ammonia, hydrocarbon; Flamingo lily (Anthurium andraeanum) absorbs toluene, xylene, formaldehyde, ammonia and hydrocarbon; Bamboo palm (chamaedorea seifrizii) absorbs toluene, xylene and formaldehyde; Lady palm (Rhapis excelsa) absorbs toluene, xylene, formaldehyde and hydrocarbon; Snake plant, mother-in-law’s tongue (Sansevieria trifasciata) absorbs benzene, toluene, xylene, formaldehyde and trichloroethylene; Philodendron (philodendron cordatum) absorbs toluene, xylene and hydrocarbon; Red-edged dracaena (Dracaena marginata) absorbs benzene, toluene, xylene, formaldehyde and trichloroethylene; Rubber plant (Ficus elastica) absorbs formaldehyde; Dumb canes (Dieffenbachia spp.) toluene, xylene and hydrocarbon; Aloe vera (Aloe vera) absorbs benzene and formaldehyde.
These plants can be used at variety of places under indoor conditions e.g. on the table, side of door or chair, at window, in hanging baskets etc. to remove maximum air pollution and to enhance aesthetic beautification. To fight against increasing indoor pollutants we should use variety of easily available indoor plants in our houses, offices and should educate other people regarding the use beautiful indoor plant.
This article is jointly written by Dr. Gulzar Akhtar and Dr. Ishtiaq A. Rajwana, from Department of Horticulture, Muhammad Nawaz Shareef University of Agriculture, Multan, Pakistan. Corresponding author can be reached at gulzar.akhtar@mnsuam.edu.pk.