In principle non-toxic for humans, but ...
In principle, the walnut is not poisonous to humans. However, people with sensitive stomachs can react to the leaves of the plant with nausea and vomiting, for example when drinking a tea with walnut leaves.
In addition, poisoning by the green shell of the walnut fruit cannot be completely ruled out. The reason for this is the high tannic acid content, which, with appropriate sensitivity, can cause stomach and intestinal problems such as diarrhea.
Important: Moldy walnuts should not be consumed under any circumstances - they are always harmful to your health!
Walnut is partially poisonous for animals
The heartwood of the walnut tree is poisonous for horses - it can lead to laminitis. In practice, however, there is hardly any poisoning. To do this, the horse would have to nibble on a felled walnut tree or a piece of furniture made of walnut.
The shells that house walnuts can be infested with fungi (Penitrem A) - these in turn are in the Able to develop toxins and thereby provoke vomiting, tremors and nerve cramps, especially with Dogs.
Note: The nuts themselves can also be infected with fungi and cause damage.
