Tumor induction with hexanal methylformylhydrazone of Gyromitra esculenta

Hexanal methylformylhydrazone (HMFH) was administered to Swiss mice by intragastric instillations at weekly intervals of 52 times at 50 or 100 micrograms/g body weight. The treatment induced tumors of the lungs, liver and preputial glands. The tumor incidences in the group that received the lower dose were 74, 4 and 0% in females and 78, 8 and 6% in the males. In the group with the higher dose, the incidences were 90, 28 and 0% in females and 70, 6 and 86% in males. The corresponding tumor incidences in the untreated animals were 26, 0 and 0% in females and 26, 0 and 0% in males. The histopathological examination revealed adenomas and adenocarcinomas of lungs, benign hepatomas and liver cell carcinomas, and squamous cell papillomas and carcinomas and adenomas of preputial glands. HMFH is the sixth carcinogenic ingredient found in one of the false morel mushrooms, Gyromitra esculenta. Because this fungus is considered edible, the health hazard implications cannot be discounted.

Carcinogenesis by pentanal methylformylhydrazone of Gyromitra esculenta in mice

Pentanal methylformylhydrazone (PMFH) given in propylene glycol as 52 weekly intragastric instillations on a 50 micrograms/g body weight basis, induced tumors of the lungs, liver and preputial glands in Swiss mice. The tumor incidences in these tissues were 72, 16 and 0% in the treated females, while these tumor incidences in the males of this group were 60, 2 and 12%, respectively. The corresponding tumor incidences in the propylene glycol instilled solvent control females were 26, 0 and 0%, whereas in the males of this group they were 22, 0 and 0%, respectively. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of the lungs, benign hepatomas and squamous cell papillomas and carcinomas of the preputial glands. Pentanal methylformylhydrazone is an ingredient of the edible wild mushroom Gyromitra esculenta which is consumed by a segment of the human population around the world.

Effect of Metamucil on tumour formation by 1,2-dimethylhydrazine dihydrochloride in mice

The effect of the plant cellulose metamucil on the tumorigenicity of 1,2-dimethylhydrazine dihydrochloride (1,2-DMH) was studied in random-bred Swiss mice. Three groups of mice, which were 5, 6 and 6 weeks old at the beginning of the experiment, were given the following treatments: (1) metamucil (20%, w/w) in powdered diet for their lifespan; (2) 1,2-DMH, ten weekly subcutaneous injections at 20 mg/kg body weight; (3) combination of treatments given to groups 1 and 2. The administration of metamucil enhanced the appearance of colon tumours induced by 1,2-DMH in males only. Metamucil had no statistically significant effect on the development of tumours elicited by 1,2-DMH at seven additional sites. It was expected that a high amount of dietary fibre would inhibit carcinogenesis in the large intestine. Instead, metamucil increased the incidence of colon tumours induced by 1,2-DMH, although only in males.

Lack of carcinogenicity of agaritine by subcutaneous administration in mice

Agaritine (A), an ingredient of the cultivated mushroom of commerce Agaricus bisporus, was administered by subcutaneous injection to two groups of randomly bred Swiss mice. In the first group the animals of both sexes were treated at a 100 micrograms/g body weight basis five times at weekly intervals, while in the second group the mice received a single A treatment of 100 micrograms/g body weight for females and 50 micrograms/g body weight for males. The administration of the compound resulted in no detectable carcinogenic effect in the animals. Since some of the breakdown products of A were shown to be carcinogenic in mice and the mushroom itself was found to be mutagenic, the field is discussed in the light of the obtained results.

Studies of the tumorigenic potential of 4-substituted phenylhydrazines by the subcutaneous route

4-Methylphenylhydrazine hydrochloride (4-MPH) was administered to randomly bred Swiss mice as 26 weekly sc injections of 140 microgram per gram of body weight and N'-acetyl-4-(hydroxymethyl)phenylhydrazine (AMPH) as 26 weekly sc injections of 500 microgram/g. As a solvent control, physiological saline was also given as 26 weekly sc injections of 0.01 ml/g. The 4-MPH treatment induced a significant incidence (24%) of fibrosarcomas in males. In the 4-MPH-treated females and some AMPH-treated male mice, a few soft-tissue tumors were observed; however, their appearance could not be related to treatment. 4-MPH is formed under special experimental conditions from 4-hydroxymethylphenyl-hydrazine, which is an in vitro breakdown product of agaritine, an ingredient of the cultivated mushroom Agaricus bisporus. The implications of the findings are discussed.

Carcinogenesis by a single dose of N-methyl-N-formylhydrazine

Single sc injections of N-methyl-N-formylhydrazine were given to randomly bred Swiss mice. The females received 180 micrograms per gram of body weight, while two groups of males were treated with either 120 or 100 micrograms per gram of body weight. The treatment resulted in induction of tumors of lungs with an incidence of 40% in the females. In males treated with the higher and lower doses, the incidences of preputial gland tumors were 12 and 12%, respectively. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of lungs, squamous cell papillomas, and carcinomas of preputial glands. N-Methyl-N-formylhydrazine is a constituent of the edible wild false morel mushroom Gyromitra esculenta, to which the human population is exposed in measurable quantities, sometimes at a single meal.

False morel mushroom Gyromitra esculenta toxin: N-methyl-N-formylhdrazine carcinogenesis in mice

N-Methyl-N-formylhydrazine was administered in drinking water as a 0.0039% solution to randomly bred Swiss albino mice for life starting from 6 weeks of age. The compound induced tumors of lungs, livers, blood vessels, gall bladder and bile ducts. The tumor incidences in these five tissues were 77, 46, 21, 10 and 7% while in the untreated controls they were 18, 1, 6, 0 and 0% respectively. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of lungs, benign hepatomas and liver cell carcinomas, angiomas and angiosarcomas of blood vessels, adenomas and adenocarcinomas of gall bladder and cholangiomas. The macroscopic and light microscopic involvement of the tissues with the tumors are described and some of them are illustrated. N-Methyl-N-formylhydrazine is an ingredient of the edible mushroom, the false morel Gyromitra esculenta. The findings are discussed from the viewpoint of a potential human health hazard.

Carcinogenic effects in the Syrian golden hamster of N-methyl-N-formylhydrazine of the false morel mushroom Gyromitra esculenta

N-Methyl-N-formylhydrazine (MFH) was administered in drinking water as a 0.0078% solution to randomly bred Syrian golden hamsters for life beginning at 6 weeks of age. The treatment gave rise to benign and malignant liver cell tumors, malignant histiocytomas and tumors of the gall bladder and bile ducts. The tumor incidence in these four treated tissues was 43, 34, 11,8%, while in untreated controls it was 0, 0, 0, 0%, respectively. Histopathologically, tumors were classified as benign hepatomas, liver cell carcinomas, malignant histiocytomas, adenomas and adenocarcinomas of the gall bladder, cholangiomas, and cholangiocarcinomas.

The large bowel carcinogenic effects of hydrazines and related compounds occurring in nature and in the environment

Five substituted hydrazines that induce large bowel and other types of cancer in laboratory animals are described. Two of these compounds, which originate in nature, are 1,1-dimethylhydrazine, a tobacco ingredient, and methylhydrazine, formed from a chemical present in the edible wild mushroom Gyromitra esculenta. The human population is therefore exposed to them considerably. In addition, both compounds are manufactured and used in rocket fuel. The other three chemicals, 1,2-dimethylhydrazine dihydrochloride,1-methyl-2-butylhydrazine dihydrochloride and trimethylhydrazine hydrochloride, are manufactured synthetically only and apparently are not found in substantial quantities in the environment.

Tumorigenic effects of chronic administration of benzylhydrazine dihydrochloride and phenylhydrazine hydrochloride in Swiss mice

Separate solutions of 0.015% benzylhydrazine dihydrochloride and 0.01% phenylhydrazine hydrochloride were given continuously in the drinking water of 6- and 5-week-old randomly bred Swiss mice for the remainder of their life. The consumption of benzylhydrazine dihydrochloride significantly increased the lung tumor incidence from 21 to 42% in the females, while in phenylhydrazine hydrochloride-treated mice, the incidence of blood vessel tumors rose significanly from 5 to 22% in females and from 6 to 20% in males, as compared with the controls. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of lungs and angiomas and angiosarcomas of blood vessels. The study thus proves for the first time the tumorigenicity of benzylhydrazine dihydrochloride. It also confirms the tumor inducing ability of phenylhydrazine hydrochloride, which is used in medicine for treatment of polycythemia vera.