Contact dermatitis in the context of Toxicodendron pubescens

This article lists plants commonly found in the wild, which are edible to humans and thus forageable. Some are only edible in part, while the entirety of others are edible. Some plants (or select parts) require cooking to make them safe for consumption.

Field guides instruct foragers to carefully identify species before assuming that any wild plant is edible. Accurate determination ensures edibility and safeguards against potentially fatal poisoning. Some plants that are generally edible can cause allergic reactions in some individuals. U.S. Army guidelines advise to test for contact dermatitis, then chew and hold a pinch in the mouth for 15 minutes before swallowing. If any negative effect results, it is advised to induce vomiting and drink a high quantity of water. Additionally, old or improperly stored specimens can cause food poisoning.

Rosin (/ˈrɒzɪn/), also known as colophony or Greek pitch (Latin: pix graeca), is a resinous material obtained from pine trees and other plants, mostly conifers. The primary components of rosin are diterpenoids, i.e., C₂₀ carboxylic acids. Rosin consists mainly of resin acids, especially abietic acid. Rosin often appears as a semi-transparent, brittle substance that ranges in color from yellow to black and melts at stove-top temperatures.

In addition to industrial applications such as in varnishes, adhesives, and sealing wax, rosin is used with string instruments on the bow hair to enhance its ability to grip and sound the strings, and it provides grip in various sports and activities. Rosin also serves as an ingredient in medicinal and pharmaceutical formulations and can cause contact dermatitis or occupational asthma in sensitive individuals. It is an FDA approved food additive.

Allergic contact dermatitis (ACD) is a form of contact dermatitis that is the manifestation of an allergic response caused by contact with a substance; the other type being irritant contact dermatitis (ICD).

Although less common than ICD, ACD is accepted to be the most prevalent form of immunotoxicity found in humans. By its allergic nature, this form of contact dermatitis is a hypersensitive reaction that is atypical within the population. The mechanisms by which these reactions occur are complex, with many levels of fine control. Their immunology centres on the interaction of immunoregulatory cytokines and discrete subpopulations of T lymphocytes.

Metopium or poisonwood is a genus of flowering plants in the sumac family, Anacardiaceae. They are dioecious trees with poisonous sap that can induce contact dermatitis.

Urushiol-induced contact dermatitis (also called Toxicodendron dermatitis or Rhus dermatitis) is a type of allergic contact dermatitis caused by the oil urushiol found in various plants, most notably sumac family species of the genus Toxicodendron: poison ivy, poison oak, poison sumac, and the Chinese lacquer tree. The name is derived from the Japanese word for the sap of the Chinese lacquer tree, urushi. Other plants in the sumac family (including mango, pistachio, the Burmese lacquer tree, the India marking nut tree, and the cashew) also contain urushiol, as do unrelated plants such as Ginkgo biloba.

As is the case with all contact dermatitis, urushiol-induced allergic rashes are a Type IV hypersensitivity reaction, also known as delayed-type hypersensitivity. Symptoms include itching, inflammation, oozing, and, in severe cases, a burning sensation. Additionally, smoke from burning plant matter may be toxic.