Strongest Evidence Yet Of Cancer Risk Near Power Lines
By Jonathan Leake and Chris Dignan, The Times
A British scientist has produced the most powerful evidence yet of a link between cancer and electricity power lines. His study confirms that people living near them are exposed to radiation levels dozens of times greater than the legal limit. The research, to be released this week, firmly links the power lines with childhood leukaemia and other forms of cancer. The levels recorded in some areas were two times higher than the legal maximum allowed for adult nuclear power workers — the group permitted maximum radiation exposure. Its most serious implication is that more than 23,000 homes built under or near power lines are unsafe, especially for children. The effect of the fields can extend more than 100 yards either side of the lines. Professor Denis Henshaw, of Bristol University’s human radiation effects group, showed three years ago that there was a theoretical mechanism whereby power lines could increase human uptake of the radioactive gases produced naturally in the soil and also of traffic pollutants. His latest study quantifies this effect in the field and shows that power lines are indeed linked to childhood leukaemia and other cancers. Henshaw took 2,000 field measurements to support his research. A university insider described the findings as dynamite. “The study has serious implications for the electricity industry, which could face huge compensation claims and pressure to move its pylons.” Children are especially vulnerable to radiation and pollution damage because they have more growing and dividing cells than adults. Such cells are far more prone than adult ones to become cancerous when exposed to hazardous substances. The research will be published in the International Journal of Radiation Biology. Its editor, Professor Gordon Steel, said it was a comprehensive study of how electric fields of the kind generated by power lines and, to a lesser extent, domestic appliances, could increase the uptake of radioactive gases and pollutants by humans. Details will be revealed at a press conference at the Institute of Mechanical Engineers in London on Wednesday. The study, funded by the Department of Health and the Medical Research Council, is backed by another carried out by Sir Richard Doll, due for publication in The Lancet on Friday. Doll, who discovered the link between tobacco and lung cancer, has collated details of every childhood leukaemia case in the past four years to try to find common causes, including links with electric fields. Childhood leukaemia has long been seen as a target for such studies since it occurs in clusters, suggesting a common cause that is probably linked to local environmental factors. Clusters associated with power lines have been noted for years but the electricity industry has insisted such associations were too weak to be significant. Three years ago Henshaw discovered the complex interactions between the alternating electric fields surrounding power lines and the radioactive breakdown products of naturally occurring radon gas. His theory was dismissed by the electricity industry and, more importantly, the government’s National Radiological Protection Board (NRPB). Henshaw is understood to have shown that in some areas children living near power lines could receive doses of 95 millisieverts of radiation a year, compared with the maximum for homes of one millisievert. Nuclear workers are allowed a maximum dose of 50, soon to be reduced to 20. Henshaw was unwilling to comment on the study before publication but said: “It is clear that if there is radon gas or traffic fumes in the air near pylons, then people living nearby will suffer increased exposure because of the electric field.” The National Grid and electricity distribution companies could find themselves in a difficult position. A spokesman said it was too early to comment. The findings will be welcomed by victims and their families, some of whom have tried to sue for compensation. Ray and Denise Studholme, of Bolton, launched the first legal case of its kind in Europe in 1994, when they took Norweb, the electricity supplier, to court after their son Simon, 13, died from leukaemia in 1992. They had to drop their action in 1997 after an American study, now criticised as flawed, raised doubts over a link. This weekend Ray, 51, said he would consider restarting legal action in the light of the new evidence.