MMH and DMH carcinogenicity

Daniel B. Wheeler dwheeler at
Wed Aug 15 18:17:39 EST 2001

John Chalmers <jhchalme at> wrote in message news:<3B78962D.D0918DC4 at>...
> I'm somewhat skeptical that one exposure to high levels of MMH will
> cause cancer in 50% of  exposed  humans in one week. Can you supply some references?
> --John

I was told by one of two possible sources: Nancy Smith Weber or Dr.
Denis R. Benjamin, during talks given at the Oregon Mycological
Society several years ago.

I have searched a second through Benjamin's Mushrooms: Poisons and
Panaceas, and only found the following reference, which has no
reference to cancer:

"Readers may recognize the chemical monomethylhydrazine, because it
has been employed as a rocked fuel. Reports of symtpoms very simialar
to those of gyromitrin poisoning were recorded in the early days of
the aerospace industry. Some of the best studies of MMH were done by
the military-industrial complex, which was concerned about the hazards
MMH posed to workers. (20)"

Citation for (20) is:

20. P.N. Magee, "Toxicite et metabolisme de la methylhydrazine." In
Proceedings of the Fifth International Congress on Pharmacology, ed.
R. Loomis (San Francisco: Karger, 1972), pp. 140-149.

However, in Benjamin on p 128, we read:

"...However, the false morel contains at least 11 different
hydrazines, and many of them have been shown to be actively
carcinogenic a nd highly mtagenic in the standard assays. (91-97)
These compounds routinely produce tumors in experimental animals, both
in the fresh state and as purified agents. In addition, the tumors are
produced regardless of the route of administration. It is difficult to
know precisely how many people around the world eat these mushrooms.

Citations for (91-97) are:

91. B. Toth, K. Patil, H. Pyysalo, C. Stessman, and P. Gannett,
"Cancer Induction in Mice by Feeding the Raw False Morel Mushroom
Gyromitra esculenta," Cancer Research (1992) 52(8):2279-2284.

92. B. Toth, "Carcinogenic Fungal Hydrazines," In Vivo (1991)

93. B. Toth and P. Gannett, "Carcinogensis Study in Mice by
3-Methylbutanal Methylformylhydrazone of Gyromitra esculenta," In Vivo
(1990) 4(5):283-288)

94. B. Toth, J. Taylor, and P. Gannett, "Tumor Induction with Hexanal
Methylformylhydrazone of Gyromitra esculenta," Mycopathologia (1991)

95. B. Both and C.R. Raha, "Carcinogensis by Pentanal
Methylformylhydrazone of Gyromitra esculenta in Mice," Mycopathologia
(1987) 98(2):83-89.

96. B. Toth and K. Patil, "Tumorigenic Action of Repeated Subcutaneous
Administration of N-Methyl-N-formylhydrazine in Mice," Neoplasma
(1983) 30(4):437-441.

97. B. Toth and K. Patil, "Tumorigenicity of Minute Dose Levels of
N-Methyl-N-formylhydrazine of Gyromitra esculenta," Mycopathologia
(1982) 78(1):11-16.

Also in Benjamin, p 272:

"...Even the doyen of mycophagy, Charles McIlvaine, had second
thoughts about this mushroom:

	""It is not probasble that in our great food-giving country anyone
will be narrowed to G. (Gyromitra) esculenta for a meal. Until such an
emergency arrives, the species would be better let alone." - Charles
McIlvaine and Robert K. MacAdam, One Thousand American Fungi (1900)""

"Other health risks associated with the consumption of Gyromitra
species have already been discussed in Chapter 7. Gyromitrin and its
derivatives are mutagenic, (43, 44) teratogenic, (45, 46) and
carcinogenic in amial experimental systems (47, 48) - not a good
combination, even for a mushroom that is only eaten on an occasional
basis. Although the amount of toxin in well-dried specimens is very
much reduced from that contained in fresh specimens - certainly below
the level that could cause acute toxicity - enough remains to pose a
risk for long-term carcinogenic effects."

So either I heard the carcinogenic effects from people exposed to MMH
directly from Benjamin during his book tour in either 1995 or 1996; or
I heard Nancy Smith Weber mention it during either an Oregon
Mycological Society meeting where she was guest, or possibly where she
spoke to the North American Truffling Society in Corvallis.

I apologize for not giving more accurate information from something I
heard perhaps 5 or 6 years ago.

Daniel B. Wheeler

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