Today, when we think of air pollution, we should think of transport, especially cars. Today there are about 23 million vehicles on the road in Britain, and 20 million of them are cars! The fuel they use - petrol and diesel - releases a lot of pollution in the air.
The car exhausts eject a lot of bad gases, which create air pollution. These gases can be very dangerous for children. Although the fuels are becoming cleaner, it will not be making that much difference because there are more and more cars.
There is less pollution from coal, but today's modern world still creates air pollution. Today, air pollution has not really fallen, because new bad gases are released in the air, and there are a lot of them.