Volume 12 Part 1 Article 67
Title: Toxicological and Histopathological Studies on Agaricus bisporus
Authors: I.H.S. Al-Deen, H.A.A. Twaij, A.A. Al-Badr and T.A.W. Istarabadi
The progam of evaluation of Iraqi mushrooms for their toxic properties has revealed so far at least one species (Pleurotus ostreatus) with toxic properties (Al-Deen et al. 1987). The present communication reports on a second type of mushroom, Agaricus bisporus (J. Lange) Imbach, which grows wild in Iraq. Many local cases of mushroom poisoning in both humans and animals have been attributed to this fungus. A. bisporus is distributed widely in other parts of the world and it includes the commercially grown species in North America (Smith 1975) . Unfortunately, however, there have been conflicting reports regarding its toxicity. A. bisporus is grown commercially for human consumption (Lange and Hora, 1978; Miller, 1978; Raper and Raper, 1972; Smith, 1975). On the other hand, evidence has been presented that this mushroom produces a -glutamyl conjugate of p-hydroxymethylphenyl-hydrazine (Levenberg 1961) which forms the precursor for tha toxin methylhydrazine, or monomethylhydrazine (Chilton, 1978) . It is to be mentioned that some species of Agaricus were known to be toxic in some instances (Groves, 1962; Hesler, 1960; McKenny, 1971, Miller, 1972; Smith, 1975).
Highly poisonous mushrooms produce abdominal pain, nausea, vomiting, diarrhea, renal shut down, convulsion, coma and death. The onset of symptoms of poisoning may begin within 30 min. of ingestion of the mushroom, but could take several hours or even days depending on the potency of the toxins.
The present work represents a toxicological and histopathological study of the mushroom A. bisporus.