Cigarette butts and roads?
Australian researchers have discovered that cigarette butts not only make roads more durable but also mean they generate less heat.
Cigarette butts- toxic waste for recyclingBecause they filter tobacco smoke, cigarette butts contain an incredible number of toxic substances – in particular heavy metals: arsenic, nickel, chromium, mercury, etc. Every year, 4,300 billion cigarette butts are thrown down on the streets around the world. Unfortunately, most of them end up in the environment. Thrown on the ground, runoff water washes them through the sewers, into the rivers and out to sea. The toxic substances they contain leach out into the water and the soil, contaminating the surrounding fauna and flora. Every butt is a small-scale toxic bomb for the environment. So how can the pollution they generate be reduced?
Mixing butts with asphalt to improve roadsThis is the question that Professor Abbas Mohajerani and his team of researchers at the Royal Institute of Technology in Melbourne have been trying to answer. Over the years, they have tried mixing butts with various building materials. Their first satisfactory results came with a brick containing 1% cigarette butts. They realized the brick needed less heat to cook and was much more resistant to shocks than conventional bricks.
Encouraged by this discovery, the researchers then mixed butts with asphalt, one of the materials used for road surfacing. Surprise! Not only was the road very durable, in particular when used by large trucks, but researchers also noticed that the road surface emitted much less heat because it is retained by the butts. Usually asphalt reflects the sun’s heat, which then warms the atmosphere.
What about all the toxic substances in the butts? The researchers thought about that too: before mixing them with asphalt, they are encapsulated in a mixture of bitumen and paraffin. This creates an airtight layer that makes it impossible for any toxic substances to leach out into the soil.
This discovery could not only offer a solution that reduces the pollution generated by cigarette butts, but also a way of preventing temperatures rising - especially in cities. Now all that’s left to do is organize a massive collection of cigarettes butts!