In the absense of a model for a mechanism casuing biological damage/upset,
it's a bit difficult to get quantitative measurements of the relevant
"problem."  In the case of HV power lines, for instance, I'll bet you can
measure substantial differences in ozone concentrations as well as electric
or magnetic fields.  Given the lobster situation someone mentioned, you could
even have tertiary effects like the EM field "attracting" certain harmful
microorganisms (or animals that are carriers for harmful microbes, etc...)

BillW

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