Poisonous Plants

Do you know which plants are poisonous?

We can all name a few poisonous plants, and possibly even identify them, but many of them will come as a surprise. Perfectly safe plants may be wrongly considered poisonous; particularly if your child has just eaten some. There is room for us all to increase our knowledge of which plants are poisonous.

Staff of the Medical Toxicology Information Services (MTIS) of Guy’s and St Thomas’ NHS Foundation Trust, London, work with the Royal Botanic Gardens, Kew, to find new ways to help. The MTIS (as Guy’s Poisons Unit) has handled emergency poisoning enquiries from doctors and nurses since 1963. They have an active interest in poisonous plants, particularly the importance of their correct identification and the on-going assessment of their toxicity.

Book

New for May 2010 – Kew has published Poisonous Plants – a guide for parents and childcare providers.

• Information leaflet
• LOOK INSIDE

The largest group at risk from poisonous plants are children under the age of 5. They spend time around plants in homes, gardens, parks and the countryside. This accessible guidebook provides important information for anyone responsible for keeping children safe: parents and other childcare providers such as childminders, nurseries and grandparents. In addition, educators, medics, sellers of plants and flowers, gardeners and those responsible for plants in public places will find this to be an invaluable resource. It will enable you to assess the potential risks posed to children by toxic plants and provides ideas for designing and planting a safe environment.

Helpful descriptions and more than 230 photographs will assist you in identifying 132 of the most poisonous plants and plant groups likely to be encountered as pot plants, in flower beds and vegetable plots, and in more natural environments. The toxins contained in each plant (especially in plant parts that are attractive to children) and the likely symptoms should they be inadvertently touched or eaten are explained.

An illustrated section includes some of the most commonly eaten low-toxicity berries.

Identification CD-ROM

In 2000, Kew and the Medical Toxicology Information Services published Poisonous Plants and Fungi in Britain and Ireland - interactive identification systems on CD-ROM. It is used by many Accident & Emergency Departments in hospitals around the country, as well as by parents, local authorities, and other interested people. By answering simple questions about the plant or fungus you can make an identification, confirmed by a comprehensive set of photographs. Detailed information about the toxicity of the plant or fungus can then be read and printed, including: poisonous parts, toxins (poisonous chemicals), symptoms and treatment advice. The CD-ROM, priced at £15.99, can be purchased from www.kewbooks.com.

Buying a Plant

When you go to your local garden centre to choose plants for your house or garden, look carefully at the labels. As well as telling you things like the name of the plant, how big it will grow, and how much sun it likes, you will also see a warning if the plant is poisonous. For example, labels for the common houseplant dumbcane (Dieffenbachia) should say “CAUTION toxic if eaten/ skin and eye irritant”.

Kew and the Medical Toxicology Information Services compiled detailed reports on the toxicity of cultivated plants. We worked with the Horticultural Trades Association (HTA), in collaboration with the Royal Horticultural Society, to produce a list of plants that should carry warnings. To view this list and the label warnings, see The HTA list of potentially harmful plants (pdf).

Poisonous Plants – a guide for parents and childcare providers (see above) is the first book to illustrate and describe the toxicity of all the 117 plants on the HTA’s list of potentially harmful plants and includes the HTA’s risk code for each one.

Poisoning Enquiries

Cases of suspected poisoning, and questions about the toxicity of plants, are routinely handled by the enquiry service of the Centre for Economic Botany.

Urgent cases - During weekday office hours we provide a telephone advice service for urgent poisoning case enquiries. Please telephone Kew's central phone line on 020 8332 5000, stating whether the enquiry concerns a plant or a fungus (mushroom/toadstool).

Non-urgent cases - We welcome information about plant poisoning cases as very few are formally published. If you would like to tell us about a non-urgent recent or old case of plant poisoning following contact with a plant or after eating it, please print out this questionnaire and post it to the address below. Any information we receive will be treated in total confidence.

General enquiries – Any general enquiries about plant toxicity should be addressed in writing to:
Centre for Economic Botany
Royal Botanic Gardens, Kew
Richmond
Surrey
TW9 3AE

Fax: +44 (0)20 8332 3717
Email: ceb-enq@kew.org

The work on poisonous plants and fungi undertaken jointly by Kew and the Medical Toxicology Information Services has been made possible by donations and grants. The generous support of the following organisations is gratefully acknowledged:

• Special Trustees of Guy’s Hospital
• British Library
• Children Nationwide
• Kirby Laing Foundation
• Trustees of the Royal Botanic Gardens, Kew

If you would like to support this work, and for further information, please contact:

Dr Elizabeth A. Dauncey
c/o Centre for Economic Botany
Royal Botanic Gardens
Kew
Richmond
Surrey
TW9 3AB

Email: e.dauncey@kew.org or lizdauncey@nhs.net