Indoor pollution

Pollution from power plants, cars, and other transportation is a well-known contributor to outdoor air pollution, but indoor air pollution is often worse, up to 10 times more damaging than the air outside. Microbial pollutants like mould, pet dander and plant pollen can combine with chemicals like radon and volatile organic compounds (VOCs) to create a pretty toxic environment in your home.
Since we spend an average of 90 per cent of our time indoors and 65 per cent of our time inside our homes, according to the National Safety Council, that can add up to allergies, asthma and worse.
Everything that comes in to our homes has the potential to be harmful to our health, from the building materials and elements that hold our homes together to the furniture we sit on and the paint that goes on the walls. Indoor air pollution can be bad, but it does not have to be.
Indoor air pollution can be easy to manage once you understand where it comes from. In many cases, it comes from chemicals that are part of the things that you bring into your home. The polyurethane common in mattresses, formaldehyde and organic chemicals like dioxin, polychlorinated biphenyl (PCB) and polybrominated biphenyl (PBB) used in lots of furniture and other interior elements are all harmful to humans.
Curtains, carpets and other absorbent fabrics can help trap these nasties, along with dust, mites and other allergens, and our modern, mostly airtight homes keep them inside. Remember this, if there are chemicals and VOCs in a product, there are chemicals and VOCs that could come out, and they won't be good for you if they do.
Aside from keeping known pollutants out of our homes, there are several strategies for keeping the indoor air healthy. At the top of the list is maintaining proper ventilation, which can be done most easily by just opening up the windows at regular intervals.
Using green cleaning products can help cut back on the toxins in your home, as citrus and pine-based solvents can react with ozone to create formaldehyde. Keeping pesticides out of your garden and off your lawn can also help, as they are easy to track in on shoes and clothing.
It is also important to keep filters and vents clean, as pollutants can cycle through air ducts and central heating and cooling mechanisms.
Walking into a room filled with plants can lift the spirits, but did you know that it can be good for your health as well?
We can all probably remember enough biology to know that plants take in carbon dioxide and give off health-giving oxygen and water vapour as part of the photosynthesis process. That is why planting a tree is one of the best things we can do for the environment, the principle on which carbon offsetting tree-planting schemes are based.
But it is not only carbon dioxide they take in. Plants can absorb impressive amounts of other toxins and pollutants as they perform their daily functions, enabling them to act as efficient air and water filters.
In the home, this has interesting implications as our consciousness of the impact of air quality on health, particularly such conditions as childhood asthma, increases.
It might seem unlikely that mere houseplants could provide a defence, but studies have found some to be particularly effective.
One of the most efficient pollutant removers is the Dracaena, which may explain why its spiky variegated leaves on a tall central stem are so often seen in offices. It is easy to care for, reaching eight feet in ideal conditions (rich soil, warmth, light shade and sparse watering, preferably not from old coffee cups).
The goosefoot plant (Syngonium podophyllum), with its gloriously mottled and marbled leaves, is also extremely effective against all forms of air pollution - it needs a temperature of 60F (15C) and does best in bright, indirect light and a moist, loam-based soil.
But you do not have to seek out unusual plants to keep your home healthy. Another of the most efficient plants is the common spider plant, which is particularly effective against formaldehyde and the emissions from computer terminals.
Give them the conditions they really love, (good light, moist compost from spring to autumn and fortnightly feeds during the growing period), and they will reward you with cascades of miniature plants.
Ivy (Hedera helix) is another commonly found, but extremely effective plant, especially in the face of mould. A recent study found it able to remove almost 80 per cent of airborne mould and fungus spores.
And only slightly further down the scale come palms, ferns and "indestructible" office staples such as rubber plants, philodendrons, the umbrella plant (Schefflera) and the peace lily or aspidistra - good news for those without green thumbs.
For those with an aversion to glossy dark green leaves, plenty of flowering plants also combat air pollution. Chrysanthemums, gerberas, African violets, cyclamen and kalanchoes are pretty as well as effective, as are all types of orchid.
Orchids have the added advantage of being one of the few plants that produce oxygen at night, and the moth orchid, Phalaenopsis, is particularly recommended for bedrooms.
All this heroic hard work has no ill effects on the plants themselves. All they require in return is to have their watering requirements met, and their leaves occasionally sprayed with water and carefully wiped with a cloth to remove dust. It is really worth taking time to care for them properly.
So, until the next time, take care and think Green.