tt-105 BY DON MEEHAN

THE DANGER IN HERBS

This year the WSU Master Gardeners have chosen to have an educational display on herbs at the Fair. In the development of this display a concern was raised about the danger of some herbs. I asked my local resource on herbs, WSU Master Gardener Barbara Fisler, to research this topic and write about it. Here are her comments: Herbs are beautiful, useful plants that are used for flavor, fragrance, dyeing, and medicine. However, some are down right dangerous. Every year people, especially children, are poisoned by plants, sometimes because of faulty identification, sometimes by experimentation, and other times by using them in ways that are harmful. Although many herbal remedies still in use today undoubtedly have some beneficial actions and have an important part to play in modern medicine, they are not the panaceas they are sometimes claimed to be. Because they are "natural" substances, it should not be assumed that medicinal plants are completely safe and free from side effects. Like any foreign chemical introduced into the body, many normally harmless medicines can be poisonous. This can happen when taken to excess, in strong doses, once for a long period of time, or if taken by more sensitive individuals. They may react adversely with other medicines or foods that are being taken, or aggravate a pre-existing condition. The Food and Drug Administration classifies herbs as food or food additives, but pharmacognosists (experts on chemical constituents of plants) consider these plants to be drugs. "Herbal teas are drugs, not food," states Ara Du Mardirosian, Ph.D., Professor of Pharmocognosy at The Philadelphia College of Pharmacy and Science. "They are crude complexes containing many impurities and active components with a variety of possibly undesirable effects. Some are actually too dangerous to use at all." The above quote came from Rodale's Illustrated Encyclopedia of Herbs, published in 1987 and contains information on the toxicity of plants. The Rodale Herb Book, published in 1974, does not contain this same kind of information. I have been doing some research and find the same kind of discrepancies in other books on herb and edible wild flowers. Some of the uses recommended are no longer considered safe. I've heard that Day Lilies are considered herbs because they are edible, but in a package of Day Lilies I ordered by mail there was a warning included to keep out of the reach of children; some varieties are toxic. When we say a plant is edible, what exactly do we mean? I let my grandchildren taste some of the herbs in my garden; I do not let them help themselves! To taste is not to consume in any significant amount, but children and some adults often over-indulge. There are plants that can cause skin irritation like Rue (Ruta granolian). I've never had a problem with this one; however, plants of the Euphorbia family, which include Poinsettia and some garden plants commonly called Spurge, have caused a rash like a bad burn on my hands. I use gloves to weed some of the weeds in my garden that fall into this botanical family. I guess everyone is bothered by stinging nettles, but some individuals have a more sensitive reaction to them. I was prompted to do this research because my grandchildren were taught about edible plants on two occasions. One was at a park in Seattle on a nature walk, and the other at school. At the park they were taught to eat Scotch broom (poisonous, narcotic) and pineapple weed. The person that came to school taught survival, including edible plants. I talked to Children's Orthopedic Hospital and a local pediatrician, and we all felt that children are not capable of learning plant identification. The pineapple weed may be harmless, but why should children learn to eat it? It may have been sprayed with herbicides -- there is that danger -- when eating plants that are generally considered weeds. Proper identification is important, and we shouldn't trust just one source. I bought a plant at a nursery a few years ago. It was labeled Chervil, an herb recommended for use like parsley. It took me years to properly identify it. It was Queen Anne Lace, also called wild carrot, belonging to the same family as poison hemlock, looking much like hemlock but not as poisonous, though it does cause photo sensitivity. Herbs often lack botanical names, but sometimes have labels that indicate they may be edible, such as licorice plant and curry plant. These two, when properly identified, belong to the Helichoryseam family and do not appear to be edible. This year, one nursery printed a recipe that included Tansy, a plant that was used at one time to flavor food, but has been considered poisonous as reported in the "Journal of the American Medical Association" in 1917. The other day a neighbor and her children came to visit. In my garden they saw a plant they have, and one of the children said they suck on the blossoms (Foxglove, all parts poisonous). Children should not suck on blossoms, or use plant parts for toys. Horsetail (Equisetum) and Elder have hollow stems that have been used for blow guns; both are poisonous. Compared to the limited number of culinary herbs, there are hundreds that can be described as medicinal. They were used quite often as teas. Most people are probably familiar with mint in some form as a digestive aid. Mint tea is often recommended, but there are two mints that are considered unsafe as they may cause liver damage: European pennyroyal (Mintha pulegium) and American pennyroyal (Hedicoma pulegioides). Comfry has long been recommended as an herbal tea. It is now suspected of being a carcinogen. Chamomile tea is made from the blossoms, which contain pollen, so may cause allergic reactions in some people. If drying herbs for teas or adding to food, use half as much dried as fresh. The volatile oils that give herbs their taste and smell are more concentrated in the dried product. I don't wish to discourage anyone from growing herbs -- I have a large herb garden with many herbs that are poisonous. Identification is the most important skill you need as an herb gardener, so that you can use the ones that are safe to use, and prevent any unfortunate accidents from occurring with the ones that are poisonous. Herb gardens are beautiful and children love them because they can see, touch, taste, and smell many interesting plants, but they depend on us to protect them from harm. A list of poisonous herbs that I feel are available in this area will be available from the WSU Cooperative Extension Office, PO Box 5000, Coupeville, WA 98239. 679-7327 or 321-5111, ext. 327




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