1. Wireless Technology: A review of the Science

2. How Do we Prove Causation?
Temporal Relationship
Strength of the Association
Dose-Response relationship
Consistency of the association
Biologic plausibility
Consideration of alternate explanations
Experimental evidence
Specificity
Coherence

3. What is WiFi?
Originated as a marketing term for wireless computer technology, “Wireless Fidelity”, or “WiFi” as a play on “Hi-Fi”
Radiofrequency (RF) energy is a form of electromagnetic energy generated by a source transmitter and emitted in waves
Radio and TV broadcasting, cell phones, emergency radio communications, weather radar and satellite communications all use RF energy

4. The Electromagnetic Spectrum

6. Safety Code 6 Limits: The “What” and the “Why”
RF Limits
Whole Body
Head
Trunk
Controlled Environments
0.4 Watts per kg
8 Watts per kg
20 Watts per kg
Uncontrolled environments
0.08 Watts per kg
1.6 Watts per kg
4 Watts per kg

8. Comparison of measured RF fields with Wi-Fi
RF activity being measured or calculated
Maximum time-averaged power density (W/m²)
Median time-averaged power density (W/m²)
Laptop not communicating with Wi-Fi, measured directly next to Wi-Fi access point
0.007
Laptop uploading/downloading file, measured 1 metre away from laptop Wi-Fi card
0.001
Laptop uploading/downloading file, average of measurements taken at different distances from laptop
0.04

9. Outcome Research
Review of cellular and animal studies in 2009 found no evidence of genotoxic effects of RF
Some cellular studies provided evidence that gene expression is affected at RF exposure levels close to current safety limits but it is possible that small temperature elevations may have accounted for some of the observations
Little evidence of cellular effects of RF fields below current safety limits
Would be of interest to study modulation patters and intensity variations corresponding to actual mobile phones

10. Outcome Research
Review of clinical human trials found no evidence for an association between reported symptoms of electromagnetic hypersensitivity and exposure to EMFs
Results from epidemiological studies do not provide sufficient evidence to support a clear association between mobile phone use and an increased risk of cancer

12. Conclusions
Research on potential health effects from exposure to radiofrequency energy is an active field of investigation
Given inconsistent results, it is possible to cherry pick the results of individual studies to support a variety of opinions
Using a “weight of evidence” approach is more useful for informing policy making than reliance on individual studies

13. Conclusions
There is general agreement that the exposure limits in Health Canada’s Safety Code 6 are protective
Recently published literature demonstrates that Wi-Fi RF exposures are far lower than with cell phone use
It is unlikely that all controversies will be resolved even after decades of additional research