Childhood leukaemia and distance from power lines in California: a population-based case-control study

Abstract

Background:Studies have reported an increased risk of childhood leukaemia associated with living near high-voltage electric power transmission lines that extend to distances at which magnetic fields from lines are negligible. We conducted a large records-based case-control study of childhood leukaemia risk in the population living near power lines in California.Methods:The study included 5788 childhood leukaemia and 3308 central nervous system (CNS) cancer cases (for comparison) born in and diagnosed in California (1986–2008), and matched to population-based controls by age and sex. We geocoded birth address and estimated the distance from residence to transmission lines using geographic information systems, aerial imagery, and, for some residences, site visits.Results:For leukaemia, there was a slight excess of cases within 50 m of a transmission line over 200 kV (odds ratio 1.4, 95% confidence interval 0.7–2.7). There was no evidence of increased risk for distances beyond 50 m, for lower-voltage lines, or for CNS cancers.Conclusions:Our findings did not clearly support an increased childhood leukaemia risk associated with close proximity (<50 m) to higher voltage lines, but could be consistent with a small increased risk. Reports of increased risk for distances beyond 50 m were not replicated.

Residential magnetic fields exposure and childhood leukemia: a population-based case–control study in California

“…The study design, including methods of case ascertainment and control selection [21], methods for calculated fields [22], and estimation of distance from birth residence to transmission lines and associated risks [14] have been previously described. We summarize them briefly here.…”

“…We previously reported on childhood leukemia risk in relation to the distance from birth address to nearby power transmission lines [14]. The current paper presents analysis of childhood leukemia risk in relation to the residential exposure to extremely low-frequency magnetic fields from nearby transmission lines and is the first study of calculated fields and childhood leukemia in the US.…”

“…Such surrogates include the configuration of power line wiring, from both distribution and high voltage overhead transmission lines [5–7]; present day measurement of magnetic fields within residences [8, 9] or present day personal measurements [10, 11]; distance to transmission lines [12–14]; or historical calculated fields [15–20]. Each approach has distinct advantages and limitations.…”

The Stem Cell Division Theory of Cancer

“…Another pooled analysis published the same year, which included 15 studies based on less restrictive inclusion criteria, showed a relative risk of 1.7 for exposure above 0.3 μT [29]. New studies are in line with these large pooled analyses [30,31,[174][175][176]. For example, a meta-analysis based on 11,699 cases and 13,194 controls showed that the relative risk was 1.57 for exposure above 0.4 μT [31].…”

A Plausible Biological Mechanism by which Extremely Low-Frequency Electromagnetic Fields Increase the Risk of Childhood Leukemia

“…Latter, a pooled analysis of seven studies published after 2000 reported a 1.4-fold increase in childhood leukemia among children with exposures of 0.3 μT or higher [6]. New studies are in line with these large pooled analyses, typically showing relative risks between 1.5 and 2 [7][8][9][10]. For example, in a meta-analysis based on 11,699 cases and 13,194 controls, the relative risk was 1.57 for exposure above 0.4 μT [10].…”