Linseed is seriously dangerous.
I worked once as a sampler, going round farms climbing to the top of piles of wheat and barley, taking samples for the lab. We were warned about linseed
Grains form piles because the individual grains are rough, and dont slip or slide against each other. If you take a tub of linseed and pour it, it wont form a heap. The seeds are small smooth shiny and hard - the stuff flows like water.
Consequently, Linseed is stored in silos. Now, whereas you can stand on the top of a silo full of wheat, on the wheat surface, if you climb into a silo full of linseed, it behaves like water, you'll simply sink to the bottom and drown on it. Approx one person a year in the UK dies like this.