SOMATIC AND GENETIC EFFECTS OF LOW SAR 2.45 GHz MICROWAVE RADIATION ON WISTAR RATS

The somatic and genetic effects of 2.45 GHz Microwave radiation (MWR) on male and female

Sprague Dawley rats were studied. Two hundred rats were used for this study. They were

grouped into control and exposed according to the parameters under consideration. The animals

were exposed to various levels of specific absorption rate (SARs) using the microwave

generator, model ER660E, Serial No MX704CCR from Toshiba UK Ltd. All animals were kept

in healthy, and radiation free environment with water and feed provided ad libitum. The study is divided into three parts; firstly, the effects of MWR on the anxiolytic and exploratory behaviour of the animals. MWR produced dose-dependent significant decrease in the cumulative time spent in the open arms of maze in the first twelve days after exposure and gradually increased towards the control value before the end of two weeks. It also affects the exploratory behavoiur of the animals, for the first two weeks after exposure but by the third week there was no significant difference between the control and the exposed animals. The modifications in the behaviour were not sex dependent as there were no significant differences between male and female rats. Secondly, the effects of MWR on the vital organs of male and female most especially, male reproductive functions were studied. The sperm count, gross motility and sperm morphology were determined using standard methods. The results showed that 2.45 GHz MWR reduced the sperm concentration, gross motility while increasing the percentage abnormal sperm cells. There was a decrease in reproductive organ weights and increased dead sperm cells as large numbers of the sperm cells membranes took up the eosin-nigrosin vital stain in the exposed group. Lastly, the genotoxic effects of MWR were studied using Chromosomal aberrations, single cell gel electrophoresis (comet assay) and direct amplification of length polymorphisms (DALP). There was a significant increase in the frequency of chromosomal aberrations between control and  exposed groups. The exposure of vital mammalian cells to 2.45 GHz radiation altered the band patterns of the exposed animals, especially in the range 40 â€" 120 bp. Starting with appearance of additional peaks compared with the control which was not seen in their tail DNA before exposure to MW and these were confirmed through the densitometric gel analysis. There was a statistically significant difference in the Olive moment and % DNA in tail of the exposed animals compared with control (p < 0.05). Thus, these findings support the hypothesis that exposure to 2.45 GHz MWR at studied SARs may have potential somatic and genetic effects. 

Title page i

Certification ii

Declaration iii

Dedication iv

Acknowledgements v

Table of contents vi

List of Figures xi

List of Tables xiii

List of Plates xiv

Abstract xvi

1.1 Preamble 1

1.2 Statement of the Problem 4

1.3 Rationale for the study 4

1.4.1 Aim and Objectives 4

1.4.2 Specific Objectives 5

2.1 Microwave Origin and Spectrum 6

2.2 Generation and Uses of Microwaves 7

2.2.1 Telecommunication 7

2.2.2 Remote Sensing 8

2.2.3 Health 9

2.2.4 Navigation 9

2.2.5 Power 9

2.3 Interactions of Microwave with Biological Materials 10

 2.3.1 Thermal Mechanisms of Interaction 10

2.3.2 Athermal (Non-thermal) Mechanisms of Interaction 11 

2.4 Macroscopic Interactions 13

2.5 Microscopic Interaction -- Molecular Mechanisms 18

2.5.1 Cellular Interactions 22

2.5.2 Other Interaction Mechanisms 23

2.6 Temperature Effects 23

2.6.1 Effects: High â€" Frequency Fields Force 26

2.7 Radiometry of Non-ionizing Radiation 28

2.8 Free Radicals 29

2.8.1 Hydroxyl Radical 29

2.8.2 Nitric Oxide 30

2.8.3 Superoxide (O2-) 30

2.8.4 Hydrogen Peroxide 30

2.8.5 Trichloromethyl (CCI3) 31

2.8.6 Free Radicals and Lesion in DNA 31

2.9 Plausible Biological Mechanism 31

2.10 Non-human Studies 32

2.10.1 Thermoregulatory Responses to RF radiation 32

2.10.2 Reproductive Effects 32

2.10.3 Effects on the Blood-forming and Immune Systems 33

2.10.4 Nervous System 35

2.10.5 Behavioural Effects 36

2.10.6 Molecular, Subcellular and Cellular Effects 37

2.11 Genetic Toxicology 37

2.12 Epidemiological Investigations 40

3.1 Calibration of Microwave (MW) Source 42

3.2 Determination of Specific Absorption Rate (SAR) 42

3.3 Animal and Sample Preparations 42

3.4 Behavioural Studies 43

3.4.1 Exploratory Behavioural Activity Study 43

3.4.2 Anxiolytic Activity Study 43

3.4.2.1 Elevated Plus Maze Study 43

3.4.2.2 Y- maze Study 44

3.5 Fertility Studies 46

3.5.1 The Weight of the Specimens 46

3.5.2 Semen Collection 46

3.5.3 Sperm Motility Study 46

3.5.4 Sperm Morphology Study 46

3.5.5 Sperm Count 47

3.5.6 Histopathological Studies on the Reproductive Organs 47

3.6 Chromosomal Aberration Study from Rats Bone Marrow 47

3.7 Deoxyribonucleic Acid (DNA) Assay 48

3.7.1 DNA Extraction and Washing of the Blood Cells 48

3.7.2 Lysing of WBC and other Organs 48

3.7.3 Phenol Extraction and Precipitation of DNA 49

3.8 Quantification of DNA Sample 49

3.9 Primers 49

3.10 Amplification and Electrophoresis 49

3.