Toxic Plants: Knowledge, Medicinal Uses and Potential Human Health Risks

Abstract

A toxic plant is a plant that when touched or ingested in sufficient quantity can be harmful or fatal to man or other animals. When used in small amounts and correct proportions, these plants can be used as herbal drugs with medicinal properties. According to official sources from several countries, injurious and poisonous plants are responsible for many cases of intoxications worldwide. The beauty of these plants hides their toxicity and the unawareness potentiates these situations. Therefore, this bibliographic revision is about examples of some plants associated with poisoning but used for their medicinal properties, focusing on species with anticholinergic poisons (Atropa belladonna L., Datura stramonium L., Hyoscyamus niger L.), with calcium oxalate crystals (Philodendron spp.), with cardiac glycosides (Digitalis purpurea L.), with convulsant poisons and with nicotine-like alkaloids (Conium maculatum L., Nicotiana glauca Graham), with mitotic inhibitors (Catharanthus roseus L., Colchicum autumnale L.), with pyrrolizidine alkaloids (Senecio vulgaris L.), with sodium channel activators (Aconitum napellus L., Rhododendron spp.), with cyanogenic compounds (Hydrangea macrophylla (Thunb.) Ser.), and with toxalbumins (Abrus precatorius L., Ricinus communis L.). The knowledge about toxic plants is still insufficient and makes it so important to characterize some species that cause intoxication and lethality in humans.

Antioxidant and Cardiac Enzyme Marker Studies of Thevetia peruviana Seed Hydro-Methanol Extract in Wistar Male Albino Rats

“…Toxic plants with medicinal properties can be used as herbal drugs in small amounts and correct proportions. [8] When ingested in sufficient quantity, it can be harmful or fatal to man or other animals, which can be assayed using serum biochemical tests. These tests are frequently used in diagnosis diseases of hearts, liver, kidney, and cardiovascular system, etc.…”

“…intoxication include extreme fatigue, visual disturbances, weakness, nausea, headaches, and abdominal pain. [8] The toxic nature of Thevetia seeds was earlier reported in many experimental animals like mice, albino rats, and rabbits with severe clinical malfunctioning. [9][10][11][12] Preceding studies in Wistar rats treated with a single dose of 70% methanol extract (500 mg/kg) caused 100% mortality and LD 50 is calculated as 375 mg/kg, revealed the narrow margin of safety lies in between 250 and 500 mg/kg, on seed intake.…”

Phytobiotics, a Natural Growth Promoter for Poultry

“…Some of them have a bacteriostatic effect (sinigrin present in horseradish). The protein -myosin, can cause reproductive disorders, such as loss of coat or feathers [99]. On the other hand, aminopropionitrile, present in the lupine, contributes to the deformation of the skeleton, especially the long bones and the chest.…”

“…Resins, which are a mixture of organic acids, alcohols, phenols, esters and carbohydrates, or photosensitizing compounds (photosensitizing) are also dangerous for animals. Insoluble calcium oxalates can take the form of kidney stones in the kidneys, and their genesis comes from the oxalic acid found in many vegetables and grasses [97][98][99][100]. The content of potentially toxic substances is also influenced by the climate, soil type, companionship of other plants, as well as the method of storage and processing.…”

“…Many varieties of garden plant bulbs (daffodils, irises, narcissi, tulips) contain highly toxic alkaloids that lower blood pressure and disrupt the heart, causing neurological changes and causing diarrhea. Raw beans contain haemagglutinins that are highly toxic to chickens, damaging and clumping blood erythrocytes [99,112]. In azaleas, all parts of the plant are highly toxic and can cause digestive disorders, weakness, neurological disorders and loss of motor coordination, as well as damage to cardiomyocytes.…”