Table 2 Summary justification for the environmental factors considered but excluded from our wish-list.

Extremely Low Frequency (ELF) radiation (power lines)

Studies find elevated rates of childhood leukaemia, the most common childhood cancer, with effects seen within 600 m of power lines [43, 44, 46]. Analysis of the National Grid for England and Wales (using GIS) revealed < 8% population exposure within 600 m.

Radio Frequency (RF) radiation (radio and TV transmitters)

Inconsistent evidence for cancer effect [47]. Effects found within 10 km of the most powerful transmitters [48], of which there are approximately 20 in the UK. Population exposure < 10%.

Radon

Strong evidence found for association with lung cancer [49, 50], and an estimated 9% of lung cancer cases in Europe are attributable to radon exposure [49]. However, datasets for different regions of the UK have been prepared using different methodologies and at different resolutions, and population exposure to radon levels above the Action Level of 200 Bq/m³ in England and Wales (highest resolution data) is < 4% (our own GIS analysis).

Individual industrial pollutants

Although there is evidence for the health effects of acute (accidental or occupational) exposure to specific hazardous chemicals [51], there is little or no evidence for their health effects at environmental levels.

Nuclear facilities

Evidence for an association with health is inconsistent and not strong [52, 53]. A small proportion of the population lives in the proximity of the UK's 27 nuclear installations.

Contaminated land

The primary route of exposure for many soil contaminants is consumption of soil or contaminated vegetables [54], so << 10% population exposure. Mapping contaminated land for the UK is incomplete [55], and modelling human exposure to contaminants in soil is a highly complex process [56].