The waste output of an average American has nearly doubled in the last 40 years.

And all around the world, rubbish heaps are growing as countries industrialise.

In the mid 1990s, OECD countries were producing almost two tonnes of household and industrial waste per person each year.

Africans generate less - but more than two thirds of their rubbish is not formally disposed of at all.

Recycling levels in developed countries are climbing, but have not kept pace with increasing output.

And our hunger for the latest consumer items is leaving graveyards of complex and hazardous items such as computers and televisions.