There is no national standard governing the composition of these waste-derived fuels, they vary from batch to batch depending on the sources available. Limits have been set for maximum levels of chlorine, PCBs, sulphur and heavy metals in the fuel for each cement plant. Other toxic substances such as chlorine and bromine have no maximum levels. Many other Special Wastes end up in these fuels, some of which have no calorific value and may even lower the temperatures in kilns these include exhaust gas emission filters saturated with carbon from hospital and other incinerators.

Is this form of waste-fuel a wonderful technological fix or a cheap alternative to proper treatment of very dangerous and damaging red list substances?

Total destruction in the kilns is not guaranteed and stack fall may be spreading particles from incomplete combustion over the surrounding environment and into our food chain. New exotic chemicals and dioxins may be formed during burning, and the resultant ash from all burnings still has to be disposed of.