Today almost everyone walking down the street has at least one mobile phone in their pocket. That is because many mobile phones are upgraded every year around the world, and most people are interested in changing their old mobile phone for a new one. There has been an estimated number of 90 million unwanted mobile phones in the UK alone! This mountain weighs around 12,000 tonnes, but only about 5% of it is recycled. What makes us worried most is that mobile phones contain harmful chemicals which are released into the environment when phones begin to degrade and, in addition, large amounts of carbon dioxide are also produced during the manufacture of phones. It seems that the more modern mobile phones become, the worse our environment gets.

18. Which of the following can be inferred from the passage?