Medical/biological Study (experimental study)

The effect of long-term extremely low-frequency magnetic field on geometric and biomechanical properties of rats' bone. med./biol.

PubMed Entry

Journal web site

Aim of study (according to author)
To study the possible effects of extremely low frequency magnetic field on geometric and biomechanical properties of rats' bone.
Background/further details:
30 male rats were divided into three groups: sham exposure group (n=10) and two exposure groups (n=20)

Endpoint

• geometric and biomechanical properties of bone

Exposure
General category: magnetic field, low frequency field, 50/60 Hz (AC)

Field characteristics	Parameters
50 Hz exposure duration: continuous for 2 h/day for 10 months	magnetic flux density: 100 µT I = 0.12 A for B = 100 µT magnetic flux density: 500 µT I = 0.5 A for B = 500 µT

Exposed system:
animal (species/strain): rat/Sprague-Dawley
whole body exposure

Methods
Endpoint/Measurement parameters/Methodology

• geometric and biomechanical properties of bone: tensile test (to measure e.g. tensile strength, energy absoption capacity, toughness); cortical bone thickness (hematoxylin-eosin stain, light microscopy); cross-sectional area of the femoral shaft; femur length

Main outcome of study (according to author)
The data showed a significant decrease of cross-sectional area of the femoral shaft in rats exposed to a 100 µT magnetic field in comparison to sham exposed and 500 µT exposed rats. Maximum load (i.e. strength) increased in 100 µT and 500 µT exposed rats when compared to that of the sham exposed rats. The cortical thickness of the femurs of exposed rats (100 µT and 500 µT) was significantly decreased in comparison to that of the sham exposure group.
However, no significant differences were found in the other biomechanical parameters between the groups, such as e.g. length of the femur, energy absorption capacity, toughness of bone.
These experiments demonstrated that 100 µT and 500 µT magnetic fields could affect biomechanical and geometrical properties of rats' bone.

(Study character: medical/biological study, experimental study, full/main study, blind study)

Study funded by

• not stated/none

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