Contact-Poisonous Plants of the World

Cyanophyta (in water)

Toxicodendron vernicifluum

Urtica spp.

Australia and Oceania

Anacardium occidentale *

Cyanophyta (in water)

Dendrocnide spp.

Excoecaria agallocha

Laportea spp.

Mucuna spp.

Opuntia spp. *

Urtica spp.

Central and South America

Anacardium occidentale

Croton ciliato-glandulosus

Cyanophyta (in water)

Dieffenbachia spp.

Excoecaria agallocha

Hippomane mancinella

Hura crepitans

Jatropha urens

Metopium toxiferum

Mucuna spp.

Opuntia spp.

Urera baccifera

Urtica spp.

Africa

Anacardium occidentale *

Cyanophyta (in water)

Excoecaria agallocha

Laportea spp.

Mucuna spp.

Opuntia spp. *

Smodingium argutum

Urtica spp.

South and South-East Asia

Anacardium occidentale *

Antiaris toxicaria

Cyanophyta (in water)

Excoecaria agallocha

Girardinia leschenaultiana

Gluta renghas

Hippomane mancinella *

Holigarna arnottiana

Hura crepitans

Laportea spp.

Melanorrhoea spp.

Mucuna spp.

Opuntia spp .*

Semecarpus spp.

Swintonia floribunda

Tragia spp.

Urtica spp. (in mountains)

Guide to Contact-Poisonous Plants

By family names in botanical order, and alphabetically by scientific names within each family.

Disclaimer: The plant species listed here are toxic. This also applies to others which are not presented here. The information in this document have been compiled with care and accuracy. Correctness cannot be guaranteed, however. .

Blue-Green Algae

genus or species Microcystis spp., Anabaena spp., Lyngbya spp. etc

Different families of order Cyanophyta

Synonyms: Cyanobacteria (en), Blaualgen (de)

Occurrence: Worldwide, especially in warm regions, in seawater as well as in freshwater.

Description: These algae sometimes make water seem green in colour or sometimes form a blue-green scum on the surface. A bad (musty-earthy) smell may indicate the presence of these algae.

Effects: Chemical through algal toxins. Marine cyanobacterial dermatitis ('swimmers' itch' or 'seaweed dermatitis') is a severe inflammation of the skin that may occur after swimming in water containing blooms of certain species of marine cyanobacteria. The symptoms are itching and burning within a few