Greetings researchers, I am looking for a general consensus of how much salt in a biochar (specifically in mg/kg) would have negative implications for use in soil and therefore be considered too salty?

For a extreme example, if we pyrolysed a bag of Ramen noodles (one of the highest sodium content foods there is) into biochar and incorporated that at a 5% rate (w/w) into soil, and we knew the mg/kg Na level in advance could we say without performing a plant trial that that level would be too much in most (but not all, of course) applications?

Thanks,

-Steve