As anyone who lives in a crowded city will know, pollution on our streets is at critical level. But have you ever stopped to consider what the pollution levels might be like inside your house?
Indoor pollution? Yep, that's something you've got to worry about as well. According to the World Health Organisation, up to 4.3 million people die a year from diseases related to indoor pollution. True, a lot of indoor pollution around the world can be attributed to those who cook inside on indoor fires, and use solid fuels (like coal) to heat their homes but also, indoor pollution can stem from cleaning products, air fresheners and things like faulty boilers. In fact, in the UK alone, 40,000 people are estimated to die each year due to indoor pollution, according to a report from the Royal College of Physicians.
So what to do? You could get an air purifier. Although these can be expensive. And if Friends has taught us anything, it's that air purifiers are the fastest way to lose two great housemates (joking – obviously, get yourself an air purifier if you want).
In 1989, though, NASA found that the leaves, roots, soil and microorganisms of plants can also help reduce indoor pollution. They recommend having one plant per every 100 square feet of house. But some plants are more effective than others.
Which ones work best? Click through to find out...