... and also eyes, vegetation, forests, crops, buildings, statues, monuments .... The latest reports of the World Health Organisation show that our cities are becoming like throwbacks to an Auschwitzian nightmare. Gas chambers. More than 600 million people live in cities which have dangerously high levels of sulphur dioxide (S02) in the air; 1.2 billion suffer unacceptable levels of suspended particulate matter. Bombay, Delhi and Cal6tta rank among the 10 worst cities in this respect. Bangkok tops the list. Air pollution can even cause cancer, birth defects and brain and nerve damage. S02 in dry deposition can erode buildings, kill aquatic organisms, and damage habitats. And unless the governments round the world get serious about reduction of emissions, we will most certainly march into an asphyxiating century.