toxic with an ld50 of only 18 mg per kg body weight. the effect of the fresh herb is analgesic, cholagogic, antimicrobial, and oncostatic, with action as a central nervous system sedative. in animal tests, chelidonium majus is shown to be cytostatic. early studies showed that the latex causes contact dermatitis and eye irritation. stains on skin of the fingers are sometimes reported to cause eye irritation after rubbing the eyes or handling contact lenses. the characteristic latex also contains proteolytic enzymes and the phytocystatin chelidostatin, a cysteine protease inhibitor. cicuta spp. commonly known as water hemlock, cowbane, wild carrot, snakeweed, poison parsnip, false parsley, children's bane, and death-of-man. the root, when freshly pulled out of the ground, is extremely poisonous and contains cicutoxin, a central nervous system stimulant that induces seizures. when dried, the poisonous effect is reduced. the most common species is c. maculata; one of the species found in the western united states, c. douglasii, often found in pastures and swamps, has especially thick stems and very large and sturdy flowers which are sometimes harvested for flower displays. this is inadvisable as the sap is also toxic. cleistanthus collinus ingestion of its leaves or a dicoction of its leaves causes hypokalemia (kaliuresis and cardiac arrhythmias), metabolic acidosis, hypotension, and hypoxia. clivia miniata commonly known as natal lily, bush lily, and kaffir lily. it contains small amounts of lycorine, making it poisonous. codiaeum variegatum also known as garden croton or variegated croton. as with many of the euphorbiaceae, the sap can cause skin eczema in some people. the bark, roots, latex, and leaves are poisonous. colchicum autumnale commonly known as autumn crocus and meadow saffron. the bulbs contain colchicine. colchicine poisoning has been compared to arsenic poisoning; symptoms typically start two to five hours after a toxic dose has been ingested but may take up to 24 hours to appear, and include burning in the mouth and throat, fever, vomiting, diarrhea, abdominal pain, and kidney failure. onset of multiple-system organ failure may occur within 24 to 72 hours. this includes hypovolemic shock due to extreme vascular damage and fluid loss through the gi tract, which may result in death. additionally, those affected may experience kidney damage resulting in low urine output and bloody urine, low white blood cell counts (persisting for several days), anemia, muscular weakness, and respiratory failure. recovery may begin within 6 to 8 days. there is no specific antidote for colchicine poisoning, although various treatments do exist. despite dosing issues concerning its toxicity, colchicine is also a popular medicine at low doses, prescribed in the treatment of gout, familial mediterranean fever, pericarditis, and behçet's disease. it is also being investigated for use as an anti-cancer drug. conium maculatum commonly known as hemlock, poison hemlock, spotted parsley, spotted cowbane, bad-man's oatmeal, poison snakeweed, and beaver poison. all parts of the plant contain the alkaloid coniine which causes stomach pains, vomiting, and progressive paralysis of the central nervous system; can be fatal. it should not be confused with the trees commonly called hemlock (tsuga spp.), which, while not edible, are not nearly as toxic as the herbaceous plant. an infusion of poison hemlock is said to have killed socrates in 399 bc. consolida spp. commonly known as larkspur. young plants and seeds are poisonous, causing nausea, muscle twitches, and paralysis; often fatal. other plants in the parent genus delphinium are also poisonous and commonly called larkspur. convallaria majalis commonly known as lily of the valley. contains 38 different cardiac glycosides. coriaria myrtifolia commonly known as redoul. a mediterranean plant containing the toxin coriamyrtin, ingestion of which produces digestive, neurological, and respiratory problems. the poisonous fruits superficially resemble blackberries and may mistakenly be eaten as such. can be fatal in children. cytisus scoparius commonly known as broom or common broom. contains toxic alkaloids that depress the heart and nervous system. the alkaloid sparteine is a class 1a antiarrhythmic agent, a sodium channel blocker. it is not fda-approved for human use as an antiarrhythmic agent and it is not included in the vaughn williams classification of antiarrhythmic drugs. daphne spp. the berries (either red or yellow) are poisonous, causing burns to the mouth and digestive tract, followed by coma; often fatal. datura spp. several species commonly known as jimson weed, thorn apple, stinkweed, jamestown weed, angel's trumpets, moonflower, and sacred datura. containing the tropane alkaloids scopolamine, hyoscyamine, and atropine, all parts of these plants are poisonous, especially the seeds and flowers. ingestion causes abnormal thirst, hyperthermia, severe delirium and incoherence, visual distortions, bizarre and possibly violent behavior, memory loss, coma, and often death; it is a significant poison to grazing livestock in north america. datura has been used as an entheogenic drug by the indigenous peoples of the americas and others for centuries, though the extreme variability in a given plant's toxicity depending on its age and growing environment make such usage an exceptionally hazardous practice; the difference between a recreational dose and a lethal dose is minuscule, and incorrect dosage often results in death. for this same reason, datura has also been a popular poison for suicide and murder, particularly in parts of europe and india. reports of recreational usage are overwhelmingly negative; the majority of those who describe their use of datura find their experiences extremely unpleasant and often physically dangerous. daucus carota commonly known as wild carrot. it can be dangerously toxic to humans. daucus carota has been reported to contain acetone, asarone, choline, ethanol, formic acid, hcn, isobutyric acid, limonene, malic acid, maltose, oxalic acid, palmitic acid, pyrrolidine, and quinic acid. when in contact with wet daucus carota, skin irritation and vesication may occur. deathcamas various genera in the family melanthieae have species whose common names include "deathcamas", including amianthium, anticlea, stenanthium, toxicoscordion, and zigadenus. all parts of these plants are toxic, due to the presence of alkaloids. grazing animals, such as sheep and cattle, may be affected and human fatalities have occurred. delphinium spp. also known as larkspur. contains the alkaloid delsoline. young plants and seeds are poisonous, causing nausea, muscle twitches, paralysis, and often death. dendrocnide moroides known also as stinging tree and gympie gympie. capable of inflicting a painful sting when touched. the stinging may last for several days and is exacerbated by touching, rubbing, and cold temperatures; can be fatal. dicentra cucullaria also known as bleeding heart and dutchman's breeches. leaves and roots are poisonous and cause convulsions and other nervous symptoms. dichapetalum cymosum also known as gifblaar. well known as a livestock poison in south africa, this plant contains the metabolic poison fluoroacetic acid. dieffenbachia spp. commonly known as dumbcane. all parts are poisonous; the culprits are needle-shaped crystals of calcium oxalate called raphides, which can cause intense burning, reddening of the skin, irritation, and immobility of the tongue, mouth, and throat if ingested. swelling can be severe enough to block breathing, leading to death, though this is rare; in most cases, symptoms are mild and can be successfully treated with basic analgesics, antihistamines, or charcoal. digitalis purpurea commonly known as foxglove. the leaves, seeds, and flowers are poisonous, containing cardiac or other steroid glycosides. these cause irregular heartbeat, general digestive upset, and confusion; can be fatal. dioscorea communis also known as black bryony. all components of the plant, including the tubers, are poisonous due to saponin content, therefore it is not typically used internally. however, it has been used as a poultice for bruises and inflamed joints. it has been suggested that black bryony be used topically with caution, due to a tendency for the plant to cause painful blisters. studies have isolated calcium oxalate deposits and histamines in the berry juice and rhizomes, which may contribute to skin irritation and contact dermatitis. duranta erecta common names include golden dewdrop, pigeon berry, and skyflower. the leaves and berries of the plant are toxic and are confirmed to have killed children, dogs, and cats. erysimum cheiri also known as wallflower. it contains constituents that may affect the heart. euonymus europaeus commonly known as spindle, european spindle, or spindle tree. the fruit is poisonous, containing among other substances the alkaloids theobromine and caffeine, as well as an extremely bitter terpene. poisonings are more common in young children, who are enticed by the brightly coloured fruits. ingestion can result in liver and kidney damage and even death. there are many other species of euonymus, many of which are also poisonous. euphorbia pulcherrima known as poinsettia. its latex can cause an allergic reaction in sensitive individuals. it is also mildly irritating to the skin or stomach and may sometimes cause diarrhea and vomiting if eaten. sap introduced into the human eye may cause temporary blindness. it is known to be mildly toxic to cats, dogs, and horses. excoecaria agallocha commonly known as milky mangrove, blind-your-eye mangrove, and river poison tree. contact with latex can cause skin irritation and blistering; eye contact can cause temporary blindness. galanthus nivalis known as snowdrop. the plant contains an active lectin or agglutinin named gna for galanthus nivalis agglutinin, which is toxic. gelsemium sempervirens commonly known as yellow jessamine. all parts are poisonous, causing nausea and vomiting. often fatal. it is possible to become ill from ingesting honey made from jessamine nectar. gloriosa superba common names include flame lily, climbing lily, gloriosa lily, and fire lily. the plant is toxic enough to cause human and animal fatalities if ingested. every part of the plant is poisonous, especially the tuberous rhizomes. as with other members of the colchicaceae, this plant contains high levels of colchicine, a toxic alkaloid. it also contains the alkaloid gloriocine. within a few hours of the ingestion of a toxic amount of plant material, a victim may experience nausea, vomiting, numbness and tingling around the mouth, burning in the throat, abdominal pain, and bloody diarrhea. as the toxic syndrome progresses, rhabdomyolysis, ileus, respiratory depression, hypotension, coagulopathy, haematuria, altered mental status, seizures, coma, and ascending polyneuropathy may occur. grevillea spp. commonly known as silky oak and spiderflower. a few species such as grevillea 'robyn gordon', g. robusta, g. banksii, g. bipinnatifida, and others can cause severe contact dermatitis. hedera helix also known as common ivy. the leaves and berries are poisonous, causing stomach pains, labored breathing, and possible coma. heliotropium indicum commonly known as indian heliotrope. it contains tumorigenic pyrrolizidine alkaloids. helleborus niger also known as christmas rose. contains protoanemonin, or ranunculin, which has an acrid taste and can cause burning of the eyes, mouth, and throat, oral ulceration, gastroenteritis, and hematemesis. heracleum mantegazzianum also known as giant hogweed. the sap is phototoxic, causing phytophotodermatitis (severe skin inflammations) when affected skin is exposed to sunlight or to uv rays. initially the skin becomes red and starts itching. then blisters form as the reaction continues over 48 hours. they form black or purplish scars, which can last several years. hospitalization may become necessary. heracleum sosnowskyi commonly known as sosnowsky's hogweed. plant has toxic sap and causes skin inflammation on contact. hippomane mancinella commonly known as manchineel. all parts of this tree, including the fruit, contain toxic phorbol esters typical of the euphorbiaceae plant family. specifically the tree contains 12-deoxy-5-hydroxyphorbol-6gamma, 7alpha-oxide, hippomanins, mancinellin, sapogenin, phloracetophenone-2, 4-dimethylether is present in the leaves, while the fruits possess physostigmine. contact with the milky white latex produces strong allergic dermatitis. standing beneath the tree during rain will cause blistering of the skin from even slight contact with this liquid (even a small drop of rain with the milky substance in it will cause the skin to blister). burning tree parts may cause blindness if the smoke reaches the eyes. the fruit can also be fatal if eaten. many trees carry a warning sign, while others have been marked with a red "x" on the trunk to indicate danger. in the french antilles the trees are often marked with a painted red band a few feet above the ground. the caribs used the latex of this tree to poison their arrows and would tie captives to the trunk of the tree, ensuring a slow and painful death. a poultice of arrowroot (maranta arundinacea) was used by the arawaks and taíno as an antidote against such arrow poisons. the caribs were also known to poison the water supply of their enemies with the leaves. spanish explorer juan ponce de león was struck