A higher risk of childhood leukemia, particularly of acute lymphoblastic leukemia (ALL), was linked to high magnetic field (MF) exposure

10-06-2006

According to recent research published in the International Journal of Cancer, "Residential power-frequency MFs were labeled as a possible human carcinogen by the International Agency for Research on Cancer panel. In response to great public concern, the World Health Organization urged that further epidemiologic studies be conducted in high-exposure areas such as Japan."

"We conducted a population-based case-control study, which covered areas inhabited by 54% of Japanese children," explained M. Kabuto and colleagues, National Institute for Environmental Studies. "We analyzed 312 case children (0-15 years old) newly diagnosed with ALL or acute myelocytic leukemia (AML) in 1999-2001 (2.3 years) and 603 controls matched for gender, age and residential area. Weekly mean MF level was determined for the child's bedroom. MF measurements in each set of a case and controls were carried out as closely in time as possible to control for seasonal variation.

"We evaluated the association using conditional logistic regression models. The odds ratios for children whose bedrooms had MF levels of 0.4 mc T or higher compared with the reference category (MF levels below 0.1 mc T) was 2.6 (95% CI=0.76-8.6) for AML + ALL and 4.7 (1.15-19.0) for ALL only. Controlling for some possible confounding factors did not alter the results appreciably. Even an analysis in which selection bias was maximized did not fully explain the association. Most of the leukemia cases in the highest exposure category had MF levels far above 0.4 mc T."

The researchers concluded, "Our results provided additional evidence that high MF exposure was associated with a higher risk of childhood leukemia, particularly of ALL."

Kabuto and colleagues published their study in International Journal of Cancer (Childhood leukemia and magnetic fields in Japan: A case-control study of childhood leukemia and residential power-frequency magnetic fields in Japan. Int J Cancer, 2006;119(3):643-650).

For additional information, contact M. Kabuto, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 3058506, Japan.

This article was prepared by Clinical Oncology Week editors from staff and other reports. Copyright 2006, Clinical Oncology Week via NewsRx.com.