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Stalking the Wild Mushroom by Marian Segal Mushrooms can kill you, the Frenchman told author Peter Mayle, newly transplanted to Provence from England. "That I could believe," Mayle wrote in A Year in Provence, but it didn't explain the thigh-high rubber boot the Provenáal wore on his right leg, or the man's nervous thrusting of a stick around the roots of an old scrub oak tree "in the manner of a fencer expecting a sudden and violent riposte." "This was a new and worrying aspect of the LubÇron," Mayle wrote. "It was, as I already knew, a region full of strange things and even stranger people. But surely mushrooms, even wild mushrooms, didn't attack fully grown men." Perhaps not with an ÇpÇe, but, indeed, poisonous mushrooms can wreak havoc on men, women and children. If ingested, their toxins can cause stomach upset, dizziness, hallucinations, and other neurological symptoms. The more lethal species can cause liver and kidney failure, coma, and even death. As it happens, the Provenáal's immediate concern was not poison: "He slapped the rubber [boot] with his wooden sword and swaggered down toward me. D'Artagnan with a shopping basket ... 'Les serpents.' He said it with just the trace of a hiss. 'They are preparing for winter. If you disturb them--ssst!--they attack. It can be very grave.'" Here in the United States, Food and Drug Administration biologist John Gecan worries less about "les serpents" than about ignorance when it comes to harvesting wild mushrooms. Many edible mushrooms have toxic "look-alike" species, Gecan says, and untrained pickers often are woefully incompetent to distinguish the bad from the good. The Unskilled "People go out and harvest wild mushrooms without the foggiest notion of what they're picking. They may know what mushrooms they're looking for, but they may also mistakenly pick up toxic look-alikes found in the same place," he says. Gecan, a mushroom expert with the agency's Center for Food Safety and Applied Nutrition, says quite simply: "As a novice, you'd better not go out and pick mushrooms, eat them, and expect to live very long." FDA regulates commercially grown and harvested mushrooms, which are cultivated in concrete buildings or caves, but there are no systematic controls on individual gatherers harvesting wild species. Some of the most deadly mushrooms produce toxic amanitins. Among them is the genus Amanita, whose members have telltale common names such as death angel, fool's mushroom, and destroying angel. These, and less deadly species, may end up in gourmet shops, co- ops, supermarkets, and restaurants, mistaken for their nontoxic, edible look-alikes. Armed with illustrated books and a big jar of dried mixed forest mushrooms imported from France, Gecan demonstrates how difficult it can be to distinguish similar looking species. He emphasizes that even experts can't know all there is to know to identify every kind of wild mushroom, because of their great diversity. There are two general groups of fleshy fungi--ascomycetes and basidiomycetes--which are differentiated by their spore-bearing reproductive structures. Ascomycetes bear spores enclosed in a sac- like cell called an ascus. They include the cup fungi, false morels, and true morels. Basidiomycetes bear spores on one end of a specialized cell called a basidium. This group is further broken down into subgroups based on their spore-bearing structures and include, among others, the chanterelles, gilled fungi (including the "button" mushrooms commonly seen in supermarkets), and puffballs. Gecan, whose primary expertise is identifying morels and their look-alikes, illustrates the complexity of the task. He notes, for example, that the edible bell morel Verpa conica and half-free morel Morchella semilibera, and the poisonous early "false morel" Verpa bohemica all have caps that look like a partially closed parasol with vertical ridges and striations. The three can easily be confused by an inexperienced harvester, as their distinguishing features are not conspicuous. The edible half-free and bell morels both have eight spores per ascus, but the stem on the half-free attaches halfway up inside the cap, while the stem of the bell morel attaches at the very top of the cap. The stem of the poisonous early false morel also attaches at the very top of the cap, but it has only two to four large spores per ascus. The Unscrupulous Unskilled harvesters are not the only problem of the wild mushroom trade; the lucrative market has generated its share of unsavory characters. "There's such an economic gain to be had here that people are going out knowingly including the toxic Verpa bohemica in their harvest of edible morels. This was a serious contamination problem in morels coming from India in the late 1980s," Gecan says. He tells of an importer who admitted that some harvesters will pick up anything that looks like a morel, adding that some pickers even stuff them with stones to increase the weight. The wild mushroom business has also spawned violence. Some wild mushrooms sell for $100 or more a pound, Gecan says, and armed robberies are occurring in the Pacific Northwest, where the combination of heavy-covered forests and moist environment yields a plentiful crop. The Evidence FDA first became involved with analyzing wild mushrooms when agency field inspectors sent samples to headquarters laboratories following a poisoning outbreak in 1977. Four people suffered abdominal pains, dizziness, vomiting, and fainting after eating "veal morel" at a New York City restaurant. The morels, imported from France and Switzerland, included Gyromitra esculenta mushrooms, which produce the methylhydrazine derivative gyromitrin, a toxin that can sometimes cause death. "It's basically one of the components of rocket fuel," Gecan says. He explains that "Gyromitra is picked and canned and eaten in France and elsewhere in Europe with no ill effects, because the chefs over there know how to prepare them." In July 1978, FDA issued an import alert directing sampling of morel shipments from the French and Swiss firms implicated in the 1977 outbreak. In 1980, analysis of samples of French morels collected by FDA's Denver district showed they contained Gyromitra. In 1987, a food poisoning investigation by FDA's Detroit district led to a shipment of dried "morels" packed by two firms in India. The mushrooms contained Gyromitra as well as another toxic species, Verpa bohemica. In December 1990, the agency identified Verpa bohemica in samples of two lots of dried "morels" from a third French firm. The agency's current import alert instructs the districts to sample morels shipped from all the firms implicated in previous poisoning outbreaks and send them to Gecan for identification. Also, morel shipments from other firms--particularly in France, Switzerland and India--must be examined for proper labeling and packaging and, if necessary, sampled. When toxic species are identified, the shipment is refused entry. The Survey To determine the extent of the problem of toxic wild mushrooms in the U.S. market, Gecan and his FDA colleague, biologist Stanley Cichowicz, directed a two-year survey of wild mushrooms in commercial distribution. They published their results in the August 1993 Journal of Food Protection. For the survey, 10 FDA districts were directed to collect samples of specific species of canned, dried and fresh imported and domestic mushrooms. About two dozen species were collected at ports of entry and from gourmet shops, supermarkets, health food stores, and other commercial establishments. They included morels, false morels, shiitakes, straw mushrooms, chanterelles, hiratakes, and others, as well as mixed mushrooms. Of the 344 samples collected, toxic mushrooms were found only in the morels and the mixed mushrooms. Of the 42 morel samples collected, nine contained toxic species. Seven of the nine were from France, the other two from India. Of 13 mixed mushroom samples collected, two--both from France--contained toxic species. Although all the toxic mushrooms identified in the survey originated overseas, potential problems exist with wild mushrooms harvested here at home as well. Except for Michigan, where wild mushroom growers and harvesters must be licensed, and Illinois, which prohibits the sale of wild-picked mushrooms through wholesale, retail or food service establishments, the states do not regulate the sale of wild mushrooms. And FDA has no regulatory authority for products not sold in interstate commerce. During the survey, Gecan received a quart canning jar of mushrooms an FDA investigator bought in a Chicago bar. The investigator learned from the bar owner that some local women who had immigrated from Poland had been hired to pick the mushrooms in a Wisconsin woods. The mushrooms were packed in brine in mason jars and sold at local bars. The mushrooms turned out to be okay, Gecan says, but both the possibility of toxic mushrooms and the brine levels were cause for worry. Improper processing could have caused botulism toxicity. New World, New Species Gecan says that immigrants who commonly pick mushrooms in their native lands have particular problems when they continue that tradition here. The mushrooms in this country may look like the ones they or their parents and grandparents picked in the old country. But appearances can be deceiving. Cichowicz explains that North America has perhaps four times as many mushroom species as Europe, so European immigrants think they're picking the same mushrooms as back home, when actually they're harvesting toxic look-alikes. Immigrants from other parts of the world have similar problems. Gecan tells of a group of Koreans in the Pacific Northwest who, looking for straw mushrooms, picked death caps instead. "They cleaned them, cooked them, and ate them, and all needed liver transplants," he says. It gets still more complex, Cichowicz says, because even within different parts of this country, a particular mushroom grown under certain conditions--a certain type of soil or nutrient source--will look one way, whereas the same species grown under different conditions will have a slightly different appearance. He says a species grown east of the Rockies might be edible, whereas west of the Rockies it might not. The Clubs Not all wild mushroom harvesters are unskilled or unscrupulous. There are mycology (mushroom) clubs in the United States with extremely knowledgeable members that organize forays and gain continuing experience from their field work. Gecan recommends that interested amateurs contact a club through the North American Mycological Association. He says, "Experienced collectors should go out in the field, know every mushroom they pick, and if there's a question in their mind, should chuck it away." The common button mushroom Agaricus bisporus sold in retail markets is commercially grown under controlled conditions and presents no hazard of contamination with toxic mushroom species. But because there are no absolute guarantees that toxic mushrooms won't reach the market, Gecan endorses the maxim "buyer beware." Because of increased demand, retail food stores are offering more and more varieties of wild mushrooms, while their harvesting remains largely unregulated. That is not to say that Americans need forever forgo the taste delights of wild mushrooms. Gecan says that although toxic morel look-alikes are occasionally found in commercial mushrooms, they are rarely fatal. In addition, individuals have different thresholds for the toxins, so that some people might display only mild symptoms or none at all. Someone who gets sick from eating wild mushrooms should go to a hospital emergency room for treatment. These considerations are reminiscent of Peter Mayle's mind-set as he pondered a gift from his friend: "He had been in the forest since six o'clock, and he had a present for us. From behind his back he produced his old checked cap, bulging with wild mushrooms. He gave us his favorite recipe-- oil, butter, garlic, and chopped parsley--and told us a dreadful story about three men who had died after an ill-chosen mushroom supper. A neighbor had found them still at the table with wide, staring eyes--Monsieur Sanchez gave us a demonstration, rolling his eyes back in his head--completely paralyzed by malignant fungus. But we were not to worry, he said. He would stake his life on the mushrooms in his cap. Bon appÇtit!" n Marian Segal is a member of FDA's public affairs staff.<