1. Biological Effects of Power Line Electromagnetic Fields Troy Cok ENGR 302 May 6, 2002

2. The Issue  Power lines pass through residential areas  Concerns related to resulting electromagnetic fields (EMF)  Central question – does power line EMF cause cancer?

3. Research on the Issue  Two main fields of study Epidemological –Examination of human cancer cases WRT field locality/intensity Laboratory –Animal experimentation

4. Epidemological Studies  University of Colorado Study - 1979 Children living near power lines twice as likely to develop cancer than others First to expose the issue to the public Criticized for lack of actual field measurements

5. Many More Studies…  Numerous epidemological studies conducted in past 23 years  Research methods refined  Varied findings – no strong consensus Some report noticeable connection between power lines and cancer Others show little / non-existent relationship

6. Laboratory Research  Attempt to establish connection between electric or magnetic fields and cancer  Generally believed that magnetic fields are more dangerous than electric fields Magnetic fields can induce a small current in conducting materials Difficult to shield

7. Results of Laboratory Research  Magnetic fields shown to alter several biological processes Melatinon levels, brain & heart activity, immunities However, no changes beyond normal range  No strong consensus that EMF exposure can cause cancer

8. Future Research... ?  Some believe lack of any consensus indicates that power lines do not cause cancer  Others say the issue remains unresolved Methodological shortcomings –Residents often leave house –Epidemological measurements often taken intermittently – transients may also occur –Laboratory conditions too “perfect” – transients, current & voltage alterations

9. Should We Be Concerned ?  Local EMF’s created by household appliances are much larger than those resulting from power lines  Safety measures may be taken Limit time under high-voltage lines Do not sit in front of a computer all day

10. The End