Title: Rhubarb
Content: a 65 kg adult would need to eat 4 to 8 kg (9 to 18 lbs) to obtain a lethal dose, depending on which lethal dose is assumed. Cooking the leaves with baking soda can make them more poisonous by producing soluble oxalates. The leaves are believed to also contain an additional, unidentified toxin, which might be an anthraquinone glycoside (also known as senna glycosides). In the petioles (stalks), the proportion of oxalic acid is much lower, only about a tenth of the total acidity of 2–2.5%, which consists mostly of malic acid. The rhubarb curculio, "Lixus concavus", is a

Title: Rhubarb
Content: toxic rhubarb leaves have been used in flavouring extracts, after the oxalic acid is removed by treatment with precipitated chalk (i.e., calcium carbonate). Oxalic acid can also be found in the stalks of rhubarb, but the levels are too low to cause any bodily harm. The (median lethal dose) for pure oxalic acid in rats is about 375 mg/kg body weight, or about 25 grams for a human. Other sources give a much higher oral LD (lowest published lethal dose) of 600 mg/kg. While the oxalic acid content of rhubarb leaves can vary, a typical value is about 0.5%, meaning

Title: Rhubarb
Content: levels in diabetic mice. Rhubarb also contains the flavanol glucosides (+)-catechin-5-O-glucoside and (−)-catechin-7-O-glucoside. Rhubarb contains quinone molecules which are capable of carrying an electrical charge. In 2014, a Harvard-based team of scientists published results describing the use of the quinone AQDS, almost identical to a form found in rhubarb, in flow-batteries. Rhubarb leaves contain poisonous substances, including oxalic acid, which is a nephrotoxic and corrosive acid that is present in many plants. Humans have been poisoned after ingesting the leaves, a particular problem during World War I when the leaves were mistakenly recommended as a food source in Britain. The

Title: Rheum palmatum
Content: to verify the scientific data and treatment of Chinese Rhubarb used by Chinese pharmacopoeias. Though the root of the Chinese rhubarb is a key facet of herbal medicine, its leaves can actually be poisonous if consumed in a high enough dosage. The oxalic acid crystals found in the leaves may cause a health risk. Owing to the swelling of the tongue and throat, breathing canals become constricted, ultimately preventing breathing. Patients with "arthritis, kidney problems, inflammatory bowel disease, or intestinal obstruction" should refrain from consumption. Additionally, pregnant women should avoid all intake since Rhubarb may cause uterine stimulation. If taken

Title: Rheum (plant)
Content: its concentration in the leaf stems or petioles used in food preparation is very low, and their tart flavor instead is caused by nontoxic malic acid. The plants also produce other compounds, including citric acid and anthraquinone glycosides, and the raw or cooked leaf blades are poisonous to humans and livestock if consumed in large enough amounts. Plants in cultivation are propagated by cutting up the crowns of larger plants and by seeds. Some species are grown for their ornamental qualities, including "R. acuminatum", "R. alexandrae", "R. australe", "R. kialense", "R. palmatum", "R. rhabarbarum" and "R. ribes". The genus is

Question: Which acid is contained in rhubarb leaves, making them poisonous to eat?
Answer: Oxalic acid