Solanum Nigrum - Toxicity

Toxicity

The toxicity of Solanum nigrum varies widely depending on the variety, and poisonous plant experts advise to avoid eating the berries unless they are a known edible strain. Toxin levels may also be affected by the plants growing conditions.

All parts of the plant can be poisonous, containing toxic glycoalkaloids at 0.524% (dry weight), including solamargine, solasonine and solanine. The toxins are most concentrated in the unripe green berries, but also occur in ripe berries. Solanine levels in S.nigrum can be extremely toxic and potentially fatal. Poisoning symptoms are typically delayed for 6 to 12 hours after ingestion. Initial symptoms of toxicity include fever, sweating, vomiting, abdominal pain, diarrhea, confusion, and drowsiness. Death from ingesting plant parts results from cardiac arrhythmias and respiratory failure. Children have died after eating unripe berries, and consumption has caused livestock fatalities. Livestock have also been poisoned from nitrate toxicity by grazing the leaves of S. nigrum.

Although numerous texts state that the cooked ripe fruit of black nightshade is safe to eat, detoxification can not be attributed to normal cooking temperatures because the decomposition temperature of solanine is much higher at about 243 C. There are ethnobotanical accounts of S.nigrum leaves and shoots being boiled as a vegetable with the cooking water being discarded and replaced several times to remove toxins.