Radiation detectors can detect very low levels of radiation (far below any measurable health effects, for instance), so claiming we can still detect fallout from Chernobyl doesn't really say anything.
> In the last years values of up to several thousand becquerel per kilogram were measured in wild game and certain edible mushrooms. In Germany it is not permitted to market food with more than 600 becquerel caesium-137 per kilogram.
The numbers and actual risks don't matter to change regular people's feelings about a technology. All they know is that there was actual nuclear fallout and now the mushrooms in their forests are radioactive.
> In the last years values of up to several thousand becquerel per kilogram were measured in wild game and certain edible mushrooms. In Germany it is not permitted to market food with more than 600 becquerel caesium-137 per kilogram.