Major industries are always major contaminators. It's easy to forget this, as Britain is a country in which manufacturing and resource extraction have all but disappeared, and the current generation of young Britons is growing up with rivers cleaner than they have been, in some cases, since the start of the Industrial Revolution.

That is because British coal mines, ironworks, dye works and soap works are no longer pouring out their wastes, and as a society we have learnt (and can afford) to take pollution very seriously.

But large-scale manufacturing and resource extraction of course continue, and so does our dependence upon them – except that now, they have largely been transferred out of our sight to developing countries, many of which have no more of a pollution control infrastructure than Lancashire did in 1815.

The result, as always, is filth on a gigantic scale. What happened to the river Irwell two centuries ago is now happening to the headwaters of the Amazon. The case of Chevron in Ecuador shows us graphically that our sense of old-fashioned industrial pollution being a phenomenon of the past is simply not true; to lots of people still, it is a determinant of their lives, which has to be fought.