Haven't Anglophone guests to Switzerland complained that fish in Switzerland was generally too salty ?

The deepest lakes were chosen because it was considered that the whole stuff does not rot all at once, but quite gradually and slowly.

Not just probably true. It never was a secret. Theoretically dangerous are the old explosion devices which until the early 70ies contained dynamite and TNT, until getting replaced up from about 1975 by Semtex, most of all by Semtex-82 of course.

I caught a fish in Lake Thune the other day and brought it home to grill it. The resulting detonation killed several neighbours. The worst thing was that it was after 10pm though and the police are fining me 25 Franks for causing a nightly disturbance and CHF6.80 for fishing without a licence.

Oh you beat me to it.

On the other hand, what's the big deal, the stuff will break down in the coming centuries most ww2 vintage explosives are Ammonia based so actually biodegradable, ask me what I do with old blackpowder..
..It is the best fertilizer known to man, you should see the roses, beautiful, just don't try to pick them. :-)

And if you mull the utter stupidity of the allies dumping thousands and thousands of tons of explosives in the sea and not just your normal run of the mill playdoh verity explosives, 30.000 tons of mustard gas, up to a million tons of other nasties in Beaufort's Dyke (Irish sea) half a million tons in the Skagerrak another over a half a million tons in the North sea.
To this day if you are on the Baltic doing a bit of amber hunting you should be sure that you can tell the difference between amber and phosphor.
Look at people living in the Themse estuary, they have their fingers in their ears all day.

They did not think twice in them days they thought they were doing the right thing and now we curse them.