When I was researching the book Toxic Electricity, I would see biological reactions for up to a week afterwards. They are typically strong in the first day or two after the electromagnetic field (EMF) exposures and tail off as the week goes on. I would feel fine during the EMF exposures and start seeing weird health effects usually during sleep that night. Extended time around high voltage power lines & power poles were the worst for provoking reactions, followed by wifi and transmitting utility meters.
