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Bioelectromagnetism

lines, the possibility of alternatives, and land security. Tat same year, a report was submitted by the

MDH. Te report stated that the study was not sufciently experienced in HVDC transmission lines

and that the extremely limited information did not address the concerns of the people living near

the planned transmission line route. In the same year, the report stated the need to address the issue

of air ions. Meanwhile, the campaign of those opposed to the construction became more militant

and in 1978 the opposition escalated further, but by 1979 the transmission line started commercial

operation.

Te MDH established a program to monitor the electrical environment near transmission lines and

to study the epidemiology of the people living near the line. In 1982, the Minnesota MEQB held a public

hearing and reported following: (1) no adverse health efects of HVDC transmission lines, (2) the poten­

tial long-term efects of air ions is small, (3) there is no efect of transmission lines on Holstein cattle

productivity, and (4) there is no electrical shock to humans in the Right of Way during normal opera­

tion. It also reported that (5) there was no efect of induced currents or voltages with proper grounding

and (6) there was no efect of ozone on people or plants. Afer that, the number of protests against the

operation of the transmission lines decreased. Although the intensity of static electric and magnetic

felds generated from HVDC transmission lines are weak, there is public concern about possible biologi­

cal and health-related problems of static electric and magnetic felds produced in the vicinity of HVDC

transmission lines.

In 1983, the issue of the efects of HVDC transmission lines on humans was frst addressed by Robert

S. Banks and Roy C. Haupt. Tey conducted a human health survey on four HVDC transmission lines

(Pacifc Intertie, Nelson River, Square Butte line and CU line) operating in North America at that time

(Banks and Williams, 1983). Agricultural landowners, people living near the power lines, and employees

of the power company were surveyed to determine if there were sufering any health efects. Te results

showed no health efects. In addition, for a cross-sectional epidemiological study of HVDC transmis­

sion lines and their efects on health such as headaches, depression, allergies, and complaints, interviews

with home visits were conducted (Haupt and Nolti, 1984). Tey found that at the time of the epidemio­

logical study, the transmission lines had been in operation for 12 years. Te exposure group consisted

of 245 residents within 220 m of the power transmission lines (Right of Way) and the control group

consisted of 193 residents more than 1 km away from the transmission lines, for a total of 438 residents.

Although the population in this report was small, the data was carefully collected and analyzed so that

there was no diference in the health status between the two groups and that no health efects could be

linked to HVDC transmission lines. However, there were arguments against such report, such as that

the results are worthless because the electrical environments were not identifed (Bank and Williams,

1984; Haupt, 1984).

A Scientifc Advisory Committee formed by the State of Minnesota concluded that health and safety

evaluations of the ±400 kV HVDC transmission lines did not indicate that exposure to static electric

felds and air ions were likely health hazards (Bailey et al., 1982, 1986, 1997). It was showed that no

diference was found in milk production, calving intervals, rate of culling for reproductive problems,

and incidence of abortions before and afer the line was energized (Martin et al., 1986). Te long-term

exposure studies did not produce evidence for biological efects of HVDC transmission lines on people,

growth, and reproduction of crops and beef cattle (Angell et al., 1990).

Over the history, there was large laboratory research on static electric felds and air ions (Charry

and Kavet, 1987), but only few studies had been done for HVDC transmission lines. In the 1970s, the

HVDC transmission line was introduced and this introduction triggered interest for the assessment of

the biological efects to exposures to static electric felds and air ions. Tere are a wide variety of ions in

the atmosphere (Reiter, 1992). Tese ions can originate from both natural sources such as cosmic rays,

radioactivity, and water splashing and from artifcial sources such as the HVDC transmission lines

produced corona ions when the voltage of transmission lines is high enough to cause corona breakdown

around cable. Tere are several reviewed papers concerning the efects of air ions on humans (Alexander

et al., 2013; Perez et al., 2013).