Sir – Councillors Mitchell and Belson (Letters, January 22) respond to the accusation that the council rejected an independent assessment of the health risks of waste incineration by asking whether The Oxford Times believes the Environment Agency and the Health Protection Agency are not independent.

No one disputes their independence, but their part in this is to ensure that regulatory requirements can be met by the incinerator designs, and to check it out when one of them gets built and starts burning waste. They will not, for example, pass judgement on PM2.5s (particles under 2.5 micrometers in diameter) because these are not specifically identified in the regulations.

Regulations very often lag behind the problems they control, eg asbestos controls after decades of lethal health effects, smokeless zones after the London smogs of the 1950s, banning use of mobile phones while driving after lots of accidents.

Also, we know what is supposed to happen according to the regulations, but we know less about what really happens in practice.

The problem here is that there is likely to be lots we don’t know about dioxins and furans. Recent studies suggesting they might be responsible for the diabetes epidemic shows how little we know. (See New Scientist, September 13, 2008, http://diabetes-and-pollution.notlong.com) They are not in the waste that goes into the incinerator, they are created by the process. They are nasty persistent chemicals which have to be deposited somewhere, and it is irresponsible to create them unnecessarily — and it is certainly unnecessary to use incineration to divert our residual waste from landfill. There are better ways, and none of them create dioxins and furans (and most of them create less greenhouse gas).

Steve Gerrish, Kidlington