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Morando Soffritti

Publications and source records attributed to Morando Soffritti.

15 recordsLinked to original sources

Results of a long-term carcinogenicity bioassay on Sprague-Dawley rats exposed to sodium arsenite administered in drinking water.

Arsenic (As) is a metal found in nature whose acute and chronic toxic effects have been known for decades. Hundreds of millions of people are at risk of exposure to As and its various chemical forms which can occur in the occupational and general environment in air, water, soil, food, and medicines. Several epidemiological studies have shown that prolonged exposure to As can induce various types of malignant tumors in humans, namely, skin, lung, liver, kidney, and bladder cancers. These effects have been observed particularly in geographic areas where people are exposed to well water with high concentrations of As. While the risks of As at high concentrations are well documented, there is still a great deal of uncertainty regarding the risk of exposure to As at very low levels. This uncertainty is due to the absence of adequate epidemiological data and the insufficiency of experimental data currently available. Given the limited evidence demonstrating the carcinogenic potential of As in animals, a long-term carcinogenicity bioassay on sodium arsenite (NaAsO(2)) was performed at the Cesare Maltoni Cancer Research Center (CMCRC) of the European Ramazzini Foundation (ERF). NaAsO(2) was administrated with drinking water at concentrations of 200, 100, 50, or 0 mg/L, for 104 weeks to Sprague-Dawley rats (50/sex/group), 8 weeks old at the start of the study. The animals were monitored until spontaneous death at which time each animal underwent complete necropsy. Histopathological evaluation of all pathological lesions and of all organs and tissues collected was routinely performed on each animal. The results demonstrate that in our experimental conditions NaAsO(2) induces sparse benign and malignant tumors among treated rats. The types of tumors observed are infrequent in the strain of Sprague-Dawley rats of the colony used in our laboratory, namely, lung adenomas and carcinomas, kidney adenomas/papillomas and carcinomas, and bladder carcinomas. Notably, an elevated incidence of these types of oncological lesions is also observed among people living in geographical areas where As is present at higher concentrations in drinking water.

Animals↗

Results of long-term carcinogenicity bioassays on Coca-Cola administered to Sprague-Dawley rats.

Coca-Cola was invented in May 1886 in Atlanta, Georgia by a pharmacist who, by accident or design, mixed carbonated water with the syrup of sugar, phosphoric acid, caffeine, and other natural flavors to create what is known as "the world's favorite soft drink." Coca-Cola is currently sold in more than 200 countries and in early 2000, the company sold its 10 billionth unit case of Coca-Cola branded products. Given the worldwide consumption of Coca-Cola, a project of experimental bioassays to study its long-term effects when administered as substitute for drinking water on male and female Sprague-Dawley rats was planned and executed. The objective of the project was to study whether and how long-term consumption of Coca-Cola affects the basic tumorigram of test animals. The bioassays were performed on rats beginning at different ages, namely: (a) on males and females exposed since embryonic life or from 7 weeks of age; and (b) on males and females exposed from 30, 39, or 55 weeks of age. Overall, the project included 1999 rats. During the biophase, data were collected on fluid and feed consumption, body weight, and survival. Animals were kept under observation until spontaneous death and underwent complete necropsy. The results indicate: (a) an increase in body weight in all treated animals; (b) a statistically significant increase of the incidence in females, both breeders and offspring, bearing malignant mammary tumors; (c) a statistically significant increase in the incidence of exocrine ademonas of the pancreas in both male and female breeders and offspring; and (d) an increased incidence, albeit not statistically significant, of pancreatic islet cell carcinomas in females, a malignant tumor which occurs very rarely in our historical controls. On the basis of the results of this study, excessive consumption of regular soft-drinks should be generally discouraged, in particular for children and adolescents.

Animals↗

Results of long-term carcinogenicity bioassay on Sprague-Dawley rats exposed to aspartame administered in feed.

Aspartame (APM) is one of the most widely used artificial sweeteners in the world. Its ever-growing use in more than 6000 products, such as soft drinks, chewing gum, candy, desserts, etc., has been accompanied by rising consumer concerns regarding its safety, in particular its potential long-term carcinogenic effects. In light of the inadequacy of the carcinogenicity bioassays performed in the 1970s and 1980s, a long-term mega-experiment on APM was undertaken at the Cesare Maltoni Cancer Research Center of the European Ramazzini Foundation on groups of male and female Sprague-Dawley rats (100-150/sex/group), 8 weeks old at the start of the experiment. APM was administered in feed at concentrations of 100,000, 50,000, 10,000, 2,000, 400, 80, or 0 ppm. Treatment lasted until spontaneous death of the animals. The results of the study demonstrate that APM causes: (a) an increased incidence of malignant tumor-bearing animals, with a positive significant trend in both sexes, and in particular in females treated at 50,000 ppm (P < or = 0.01) when compared to controls; (b) an increase in lymphomas-leukemias, with a positive significant trend in both sexes, and in particular in females treated at doses of 100,000 (P < or = 0.01), 50,000 (P < or = 0.01), 10,000 (P < or = 0.05), 2000 (P < or = 0.05), and 400 ppm (P < or = 0.01); (c) a statistically significant increased incidence, with a positive significant trend, of transitional cell carcinomas of the renal pelvis and ureter in females and particularly in those treated at 100,000 ppm (P < or = 0.05); and (d) an increased incidence of malignant schwannomas of the peripheral nerves, with a positive trend in males (P < or = 0.05). The results of this mega-experiment indicate that APM, in the tested experimental conditions, is a multipotential carcinogenic agent.

Animal Feed↗

First experimental demonstration of the multipotential carcinogenic effects of aspartame administered in the feed to Sprague-Dawley rats.

The Cesare Maltoni Cancer Research Center of the European Ramazzini Foundation has conducted a long-term bioassay on aspartame (APM), a widely used artificial sweetener. APM was administered with feed to 8-week-old Sprague-Dawley rats (100-150/sex/group), at concentrations of 100,000, 50,000, 10,000, 2,000, 400, 80, or 0 ppm. The treatment lasted until natural death, at which time all deceased animals underwent complete necropsy. Histopathologic evaluation of all pathologic lesions and of all organs and tissues collected was routinely performed on each animal of all experimental groups. The results of the study show for the first time that APM, in our experimental conditions, causes a) an increased incidence of malignant-tumor-bearing animals with a positive significant trend in males (p < or = 0.05) and in females (p < or = 0.01), in particular those females treated at 50,000 ppm (p < or = 0.01); b) an increase in lymphomas and leukemias with a positive significant trend in both males (p < or = 0.05) and females (p < or = 0.01), in particular in females treated at doses of 100,000 (p < or = 0.01), 50,000 (p < or = 0.01), 10,000 (p < or = 0.05), 2,000 (p < or = 0.05), or 400 ppm (p < or = 0.01); c) a statistically significant increased incidence, with a positive significant trend (p < or = 0.01), of transitional cell carcinomas of the renal pelvis and ureter and their precursors (dysplasias) in females treated at 100,000 (p < or = 0.01), 50,000 (p < or = 0.01), 10,000 (p < or = 0.01), 2,000 (p < or = 0.05), or 400 ppm (p < or = 0.05); and d) an increased incidence of malignant schwannomas of peripheral nerves with a positive trend (p < or = 0.05) in males. The results of this mega-experiment indicate that APM is a multipotential carcinogenic agent, even at a daily dose of 20 mg/kg body weight, much less than the current acceptable daily intake. On the basis of these results, a reevaluation of the present guidelines on the use and consumption of APM is urgent and cannot be delayed.

Animals↗

Results of long-term experimental studies on the carcinogenicity of methyl alcohol and ethyl alcohol in rats.

Methyl alcohol was administered in drinking water supplied ad libitum at doses of 20,000, 5,000, 500, or 0 ppm to groups of male and female Sprague-Dawley rats 8 weeks old at the start of the experiment. Animals were kept under observation until spontaneous death. Ethyl alcohol was administered by ingestion in drinking water at a concentration of 10% or 0% supplied ad libitum to groups of male and female Sprague-Dawley rats; breeders and offspring were included in the experiment. Treatment started at 39 weeks of age (breeders), 7 days before mating, or from embryo life (offspring) and lasted until their spontaneous death. Under tested experimental conditions, methyl alcohol and ethyl alcohol were demonstrated to be carcinogenic for various organs and tissues. They must also be considered multipotential carcinogenic agents. In addition to causing other tumors, ethyl alcohol induced malignant tumors of the oral cavity, tongue, and lips. These sites have been shown to be target organs in man by epidemiologic studies.

Animals↗

Results of long-term carcinogenicity bioassays on tert-amyl-methyl-ether (TAME) and di-isopropyl-ether (DIPE) in rats.

Tert-amyl-methyl ether (TAME) was administered by gavage in extra virgin olive oil solution at concentrations of 750, 250, or 0 mg/kg bw to groups of 100 male and 100 female Sprague-Dawley rats 8 weeks old at the start of the experiment. Di-isopropyl ether (DIPE) was administered in the same manner at the doses of 1000, 250, or 0 mg/kg body weight to groups of 100 male and 100 female Sprague-Dawley rats. TAME and DIPE were each delivered in 1-mL solution 4 days a week for 78 weeks. Control animals received 1 mL of extra virgin olive oil without TAME or DIPE. At the end of the treatment period, all animals were kept under observation until spontaneous death. Under these test conditions, TAME and DIPE were found to be potential carcinogenic agents for various organs and tissues.

Air Pollutants↗

Results of long-term experimental studies on the carcinogenicity of formaldehyde and acetaldehyde in rats.

Formaldehyde was administered for 104 weeks in drinking water supplied ad libitum at concentrations of 1500, 1000, 500, 100, 50, 10, or 0 mg/L to groups of 50 male and 50 female Sprague-Dawley rats beginning at seven weeks of age. Control animals (100 males and 100 females) received tap water only. Acetaldehyde was administered to 50 male and 50 female Sprague-Dawley rats beginning at six weeks of age at concentrations of 2,500, 1,500, 500, 250, 50, or 0 mg/L. Animals were kept under observation until spontaneous death. Formaldehyde and acetaldehyde were found to produce an increase in total malignant tumors in the treated groups and showed specific carcinogenic effects on various organs and tissues.

Acetaldehyde↗

Results of long-term carcinogenicity bioassay on vinyl acetate monomer in Sprague-Dawley rats.

Vinyl acetate monomer (VAM) was administered in drinking water supplied ad libitum at doses of 5,000, 1,000, and 0 ppm (v/v) to 17-week-old Sprague-Dawley rats (breeders) and to 12-day embryos (offspring). Treatment lasted for 104 weeks; thereafter, animals were kept under control conditions until spontaneous death. VAM was found to cause an increase in total malignant tumors and in carcinomas and/or precursor lesions of the oral cavity, lips, tongue, esophagus, and forestomach. Based on these data, VAM must be considered a multipotent carcinogen.

Animals↗

Results of long-term experimental studies on the carcinogenicity of ethylene-bis-dithiocarbamate (Mancozeb) in rats.

Mancozeb, an ethylene-bis-dithiocarbamate (EBDC), has been one of the most commonly used fungicides in commercial use for several decades. Nevertheless, up to now, no adequate published experimental studies on the carcinogenicity of Mancozeb have been published. Because of the importance of the compound and of the number of people potentially exposed (workers engaged in the production and use of the fungicide, people living in agricultural areas where the compound is sprayed, and people consuming polluted products), a long-term experimental study of Mancozeb was begun at the Cancer Research Center of the Ramazzini Foundation. Groups of 150 male and female Sprague-Dawley rats, 8 weeks old at the start of the treatment, were administered Mancozeb at the concentration of 1000, 500, 100, 10, and 0 ppm in feed supplied ad libitum for 104 weeks. At the end of the treatment, animals were kept under controlled conditions until spontaneous death. Mancozeb caused an increase in (1) total malignant tumors, (2) malignant mammary tumors, (3) Zymbal gland and ear duct carcinomas, (4) hepatocarcinomas, (5) malignant tumors of the pancreas, (6) malignant tumors of the thyroid gland, (7) osteosarcomas of the bones of the head, and (8) hemolymphoreticular neoplasias. On the basis of these data, Mancozeb must be considered a multipotent carcinogenic agent.

Animals↗

Ramazzini Foundation cancer program: history and major projects, life-span carcinogenicity bioassay design, chemicals studied, and results.

The Ramazzini Foundation research program was started over thirty years ago. The features of this program are: (1) systematic and integrated project design; (2) consistency over time; (3) homogeneity of approach: key members of the team remain unchanged; and (4) choice to work on new frontiers of scientific research. The program centers mainly on three projects: Project 1: experimental carcinogenicity bioassays; Project 2: experimental anticarcinogenesis assays to identify factors and active principles (compounds) capable of opposing the onset of tumors while being suitable for preventive/chemopreventive intervention; Project 3: epidemiological studies, both descriptive and analytical, on tumor incidence and mortality in persons professionally and environmentally exposed to industrial carcinogenic risks. The project involving experimental carcinogenicity bioassays for the identification of exogenous carcinogens (environmental and industrial above all) began in 1966. This project has included 398 experimental bioassays on 200 compounds/agents using some 148,000 animals monitored until their spontaneous death. Among the studies already concluded, 47 agents have shown "clear evidence" of carcinogenicity. The results have demonstrated for the first time that (1) vinyl chloride can cause liver angiosarcoma as well as other tumors; (2) benzene is carcinogenic in experimental animals for various tissues and organs; (3) formaldehyde may produce lymphomas and leukemias; and (4) methyl-tert-butyl ether (MTBE), the most common oxygenated additive used in gasolines, can cause lymphomas/leukemias. Many of the results achieved have led to the introduction of norms and measures of primary prevention.

Animals↗