Of the conventional ways of generating electricity, nuclear has by far the least health effects. In a 2007 study titled "Electricity Generation and Health," published in The Lancet, Prof. Anil Markandya of the University of Bath and and Paul Wilkinson of the London School of Hygiene and Tropical Medicine calculated several health effects per terrawatt-hour caused by coal, lignite coal, oil, natural gas and nuclear power, both for occupational exposures and for the general public. Basing their findings on extensive peer-reviewed epidemiological studies, the authors calculated two standards: 1) deaths from air pollution and serious accidents and 2) cases of serious illness from air pollution. Of the six conventional ways of generating electricity, they ranked the same in both instances: 1) lignite coal, 2) coal, 3) oil, 4) biomass, 5) natural gas and 6) nuclear energy.
Some of the major findings were:
* 12 percent of all coal miners develop one of several potentially fatal diseases
* The effects from gas and oil are an order of magnitude lower than coal, mainly because of the size of the particulate matter.
* The most important emissions from biomass are ozone precursors, nitrogen oxides and volatile organic compounds.
* The operation of nuclear reactors is so safe that more than ten years would be needed for a single occupational death to be attributed to plant operations.
The study did not include hydroelectricity, which would be expected to have an even lower level of accident and illness. Solar and wind were not included either. However, a study conducted this year by the Caithness Windfarm Information Forum 2012 found a small but steady rate of accidental death at wind farms, as illustrated in the next graph.