EMFs--doubts linger over possible risks.

Although the data linking electric and magnetic fields (EMFs) to cancers or other diseases is "weak," a new federal review concludes that exposures to these fields "cannot be recognized as entirely safe."

Seven years ago, Congress established a federal EMF Research and Public Information Dissemination (RAPID) Program to try to find biological mechanisms that might explain the epidemiology linking EMFs to cancer (SN: 6/18/94, p. 388) and other health effects (SN: 1/10/98, p. 29). The National Institute of Environmental Health Sciences (NIEHS) summarized what RAPID had learned in a 75-page report it sent to Congress 2 weeks ago.

Overall, the report finds, epidemiological studies of human populations exposed to high EMFs have shown "a fairly consistent pattern of a small, increased risk with increasing exposure" for both childhood leukemia (SN: 11/30/91, p. 357) and chronic lymphocytic leukemia in adults. However, the fact that cellular and animal studies have failed to find any support for that link "severely complicates" the interpretation of these data, says NIEHS director Kenneth Olden in a letter accompanying the report.

Olden recommends that the federal government continue basic research on the effects of EMFs in several areas, including leukemia. Indeed, the new report identified several new findings, such as EMFs' link to reduced heart-rate variability (SN: 1/30/99, p. 70), that "may warrant additional study."