ß-ASARONE Explanation ß-asarone and calamus have not previously been evaluated by the Joint FAO/WHO Expert Committee on Food Additives. ß-asarone (cis-isomer of 2,4,5-trimethoxy-l-propenylbenzene) is a constituent of oil of calamus, a flavouring agent derived from the dried rhizome of Acorus calamus Linn. The ß-asarone content of calamus oils varies with source of the plant. Indian Acorus calamus from the Jammu area is tetraploid and yields an oil containing approximately 75% ß-asarone; Acorus calamus from Kashmir is hexaploid and yields an oil containing approximately 5% ß-asarone (Vashist & Handa, 1964). The European variety of the plant is diploid and also yields an oil with approximately 5% ß-asarone (Larry, 1973). Normally, only the oil of the diploid variety is used for flavouring aromatic alcoholic beverages (Usseglio-Tomasset, cited in Larry, 1973). The roots and rhizomes of Acorus calamus have been used in the Ayurvedic system of medicine for treating a variety of diseases such as epilepsy add hysteria (Madan et al., 1960). BIOLOGICAL DATA BIOCHEMICAL ASPECTS Absorption, distribution and excretion A small amount of ninhydrin-positive material was excreted in the urine of rats following administration of ß-asarone in doses of 75-300 mg/kg bw i.p. Trans-asarone yielded 10-15 times the amount found with the cis-isomer in the same doses. The substances were not identified but were postulated to require the presence of the allyl or propenyl double bond for formation (Oswald et al., 1969). Similar ninhydrin-positive materials excreted after the administration of safrole were later identified as tertiary amino propiophenones (Oswald et al., 1971). TOXICOLOGICAL STUDIES Special studies on microbes and insects An essential oil of Acorus calamus, with an asarone content of approximately 80%, showed an in vitro antitubercular action and inhibited the growth of gram-negative organisms. The oil was also toxic to flies (Chapra et al., 1957). ß-asarone had an anti-gonadal action on the insect Dysdereus koenigii; it did not act as a juvenile hormone nor as an antiallatotropic compound (Saxena et al., 1977). Special studies on mutagenicity ß-asarone, at concentrations of 2-200 µg/plate, was not mutagenic in the Ames test with Salmonella typhimurium strains TA-98, TA-100, TA-1535, TA-1537, and TA-1538 with metabolic activation. Activity without metabolic activation was apparently not tested (Hsia et al., 1979). alpha-asarone was inactive in the Ames test (Salmonella typhimurium TA) with and without activation at concentrations of 50 ppm and 5000 ppm (0.005 and 0.5%). In a similar study with ß-asarone, ß-asarone was inactive at the 50 ppm (0.005%) level, but was active at the 5000 ppm (0.5%) level with activation (Yabiku, 1980), Special studies on pharmacology The distilled volatile oil of roots and rhizomes of an Indian variety of Acorus calamus, in doses of 20-100 mg/kg bw, (1) prolonged sleeping time with pentobarbital, hexabarbital and ethanol in mice, (2) lowered body temperature in mice, (3) increased the toxicity of Metrazole in rats, and (4) had no effect on amphetamine toxicity in aggregated mice but potentiated the action of reserpine in reducing amphetamine toxicity in this circumstance. In anaesthetized cats, doses of 1-32 mg/kg bw decreased blood pressure and increased heart rate. The blood pressure was not affected by carotid occlusion, atropinization, adrenergic or ganglionic blockage or spinal preparation. Treatment with the oil dilated blood vessels of the splanchnic area in cats and constricted the vessels of the frogs hind leg. The oil prevented the action of acetylcholine, histamine, and barium chloride on isolated guinea-pig ileum (Dandiya & Cullumbine, 1959). The hypnotic-potentiating action of Indian Acorus oil was only partially blocked by LSD in contrast to the potentiating action of reserpine which was completely blocked. Mice treated with Acorus oil, 50 mg/kg i.p., become ataractic (sedated without any marked decrease in awareness); combined treatment with iproniazed and Acorus oil resulted in excitation (Dandiya et al., 1959b). The volatile oil of European Acorus calamus had a similar hypnotic-potentiating effect to that of the Indian oil (Dandiya et al., 1959a). The essential oil of Indian Acorus calamus had a quinidine-like action in combating auricular fibrillation and flutter and ventricular fibrillation in anaesthetized dogs and in preventing or abolishing veratrine action on isolated frog muscle. It protected against electrically induced seizures but not Metrazol seizures in the rat (Madan et al., 1960). Pretreatment with Indian Acorus oil had a reserpine-like action in depleting rat brain of noradrenaline and 5-hydroxy-tryptamine (Malhotra et al., 1961). Incubation of rat brain homogenates with Acorus oil inhibited oxygen uptake; LSD partially blocked the in inhibition whereas 5-hydroxy-tryptamine potentiated the inhibition (Dhalla et al., 1961). The hypnotic potentiating action of Indian Acorus oil was reduced by pretreatment with LSD or dibenzyline (DBZ) in mice. A combination of LSD and DBZ potentiated barbiturate sleeping time; this action was not affected by Acorus oil which suggests the action of Acorus oil may be mediated through serotonin and catechol amines as the action of reserpine is. Acorus oil also significantly decreased the disappearance of pentobarbital from the blood in dogs (Malhotra et al., 1962). Indian Acorus oil, in doses of 10-100 mg/kg bw i.p. had a sedative-tranquillizing action in rats, mice, cats, dogs, and monkeys. Doses of 25 and 50 mg/kg bw produced vomiting in cats, dogs, and monkeys. Doses of 10-150 mg/kg bw i.p. depressed spontaneous and forced muscle activity in mice, with the greater depression in spontaneous activity. Acorus oil inhibited overt somatic reflexes but did not appreciably affect the neuromuscular function in the anaesthetized cat since stimulation of the reticular formation overcame the patellar reflex inhibition. These actions suggest an action of Acorus oil at the spinal cord and subcortical levels of the CNS. Acorus oil in vitro inhibited monoamine oxidase activity and 1- and d-amino acid oxidase activity of rat liver and kidney (Dhalla & Bhattacharya, 1968). Dandiya et al. (1959a) considered the hypnotic-potentiating activity of the Indian oil to be in the hydrocarbon fraction or in an oxygenated fraction not removed by the methods used in fractionating the oil. Asarone, ß-asarone, and a third substance, not identified, were considered to be responsible for the hypnotic-potentiating action of the Indian oil (Baxter et al., 1960). ß-asarone doubled sleeping time with sodium pentobarbital in mice at a dose of 50 mg/kg bw i.p. and doubled the sleeping time with ethanol at a dose of 75 mg/kg (Seto & Keup, 1969). The action of asarone and ß-asarone, alone or in combination with either reserpine or chloropromazine, on conditioned avoidance behaviour in rats, fighting behaviour in mice, and electroshock convulsions in rats was determined. Both asarone and ß-asarone alone blocked conditioned avoidance behaviour in some rats. Asarone suppressed fighting behaviour; ß-asarone did not. Asarone potentiated the action of reserpine and chlorpromazine on conditioned avoidance behaviour and fighting behaviour; ß-asarone did not. Asarone protected against electroshock convulsions, but ß-asarone increased duration of spasm. Asarone potentiated the lethal effect of chlorpromazine during electroshock convulsions; ß-asarone did not. Pretreatment with Acorus oil, asarone, or ß-asarone did not increase the concentration of 5-hydroxytryptamine in rat brain (Dandiya & Menon, 1963). Special studies on teratogenicity Chicken embyro Eggs were inoculated in the vitelinum sac with 0.2 ml of a solution containing 0.15 to 15 mg of European oil or Indian oil, or oil deprived of ß-asarone, and ß-asarone or 0.04-4.0 mg of alpha- or ß-asarone. There was an absence of teratogenic effects due to the calamus oil and alpha-asarone. In the case of ß-asarone at the 0.04 mg/egg, 43% of the embryo survived. At 4.00 mg/egg of ß-asarone, there was 100% lethality (Yabiku, 1980). Acute toxicity LD50 Material Animal Route (mg/kg bw) Reference ß-asarone Rat Oral 1 010 Taylor, 1981 Acorus oil Rat i.p. 221 Dandiya & (Indian) Cullumbine, 1959 Mouse i.p. 177 Dandiya et al., 1959a Guinea-pig i.p. 2.75 Chopra et al., 1957 Calamus oil Rat Oral 8 880 von Skramlik, 1959 (cited in Opdyke, 1977) Calamus oil Rat Oral 777 Jenner et al., (Jammu) 1964 Calamus oil Rat Oral 4 331 Taylor, 1981 (Kashmir) Calamus oil Rat Oral 3 497 Taylor, 1981 (European) Calamus oil Mouse i.p. 154.5 ± 1.1 Yabiku, 1980 (Indian) Calamus oil Mouse i.p. 1 139 Yabiku, 1980 (European) LD50 Material Animal Route (mg/kg bw) Reference Calamus oil Mouse i.p. 1 709 Yabiku, 1980 (European free of and ß-asarone) alpha-asarone Mouse i.p. 225.5 ± 1.1 Yabiku, 1980 ß-asarone Mouse i.p. 184.2 ± 1.0 Yabiku, 1980 Short-term studies Rat Jammu oil of calamus (JOC) was fed in the diet to groups of 10 male and 10 female rats at 0, 0.1, 0.25, 0.5, and 1.0% for 18 weeks. Growth was depressed at all levels and mortality increased at levels of 0.25% and greater; gross liver changes and fluid in the abdominal and/or pleural cavities were observed at necropsy in rats fed these levels. These levels also produced dose-related microscopic pathology in the liver and heart. The hepatic changes consisted of variation in hepatic cell size with distortion of architecture, capsular thickening proliferation of bile duct epithelium, and portal area fibrosis with haemosiderin deposition. The heart changes consisted of degeneration characterized by slow necrosis of muscle fibres, early fibrosis, and infiltration with mononuclear cells (Hagan et al., 1967; Taylor et al., 1967). Groups of 11 male and 11 female rats received dietary levels of 0, 0.27, 1.67 and 5.3% of a hydroalcoholic extract of the rhizome of Acorus calamus (European variety) for 13 weeks. An additional group of the same size received 0.1% Jammu oil of calamus (JOC) in the diet. The ß-asarone content of the diet was 0, 30, 184 and 583 ppm (0, 0.003, 0.0184 and 0.0583%) respectively, for the hydroalcoholic extracts, and 710 ppm (0.071%) for the JOC diet, on the basis of analytical data in the report. Growth depression was noted in the JOC-treated group. No gross or microscopic effects or effects on haematology, clinical chemistry, urinalysis, or organ weights was found in any of the test groups (Weinberg, 1969). The short-term toxicity of JOC, European oil of calamus (EOC) and Kashmir oil of calamus (KOC) administered in the diet or by gavage was compared in rats. Groups of 10 male and 10 female rats received 0, 1.0% JOC, 1.0% EOC, or 1.0% Koc in the diet or 0 (7 ml corn oil/kg bw), 250 mg JOC/kg, 847 mg EOC, or 1082 mg Koc/kg by gavage daily, seven days a week for 9-14 weeks. In the feeding study, atrophy of cardiac muscle cells (JOC, EOC, Koc), fatty infiltration of the myocardium (JOC only) and cardiac fibrosis (JOC, EOC) were observed. Hepatic damage was also produced by dietary administration with the JOC rats showing the most serious effects. Fatty degeneration occurred in the centro-lobular region indicating its association with chronic passive hyperaemia. Hepatic passive hyperaemia was observed in all groups, including the controls, but was most prominent in the JOC rats and was considered indicative of cardiac insufficiency. Coagulative necrosis in the centro-lobular region, hepatic fibrosis, and bile duct hyperplasia were also observed in the JOC rats. Heart and liver damage of the same types seen in the feeding study were observed in the gavage study. The severity of heart damage and liver damage was in the order JOC, EOC, Koc (Taylor, 1981). Guinea-pig Groups of four male and two female guinea-pigs were treated with 0 (untreated control), 0 (solvent (olive oil) control), or 0.01 ml Indian Acorus oil/100 g bw i.p. daily, six days a week, for six weeks. No effects on physical condition or gross pathology were observed. Hard nodules, considered due to local irritation, formed at the site of the injections, but these disappeared in a few days (Chopra et al., 1957). Long-term studies Rat Groups of 25 male and 25 female rats were fed diets containing 0, 400, 800, or 2000 ppm (0, 0.04, 0.08, or 0.2%) ß-asarone for two years. A positive control group of the same size received 2500 ppm (0.25%) JOC. None of the group receiving 2000 ppm (0.2%) ß-asarone or 2500 ppm (0.25%) JOC survived more than 84 weeks; mortality was also increased on the 800 ppm (0.08%) dose. Median survival time in the females was less than in the males in these groups. The gross pathological changes observed were serous fluid in the abdominal and pleural cavities, liver and kidney changes, and tumourous masses in the intestinal tract. The tumours were identified as leiomyosarcomas of the small intestine and were found in one rat on 400 ppm (0.04%), six on 800 ppm (0.08%), nine on 2000 ppm (0.2%) and one on 2500 ppm (0.25%) JOC. All the test rats with leiomyosarcomas were males. The earliest tumour was observed in a rat 52 weeks old on the 2000 ppm (0.2%) dose. Two leiomyosarcomas were also noted in control females but the location differed from that of the tumours in the treated animals. Atrophy of cardiac muscle cells occurred in controls and all test groups but was most prominent in the 2000 ppm (0.2%) ß-asarone and 2500 ppm (0.25%) JOC groups. Cardiac fibrosis generally paralleled the incidence of cardiac atrophy. Fatty degeneration and fatty infiltration were also in the heart more severe in the treated groups. Thrombosis within the chambers of the heart was observed in the 800 and 2000 ppm (0.08 and 0.27%) ß-asarone and 2500 ppm (0.25%) JOC treated groups. Passive hyperaemia of the lung, kidneys and liver was more prominent in the test than control animals indicating faulty cardiac function in the test animals. Incidence of hepatic angiectasis and hepatic coagulative necrosis also tended to increase with increasing ß-asarone dose. Both sexes on 800 and 2000 ppm (0.08 and 0.2%) ß-asarone and 2500 ppm (0.25%) JOC had slightly depressed body weights throughout the study; the males on 400 ppm (0.04%) ß-asarone also had depressed body weights at termination but the number of survivors was small. Haemoglobin, haematocrit, and red and white cell counts were normal except that when the test animals became sick they became anaemic with lowered haemoglobin, haematocrit, and red cell count (Taylor, 1981). Groups of 25 male and 25 female rats were fed diets containing 0, 500, 1000, 2500 and 5000 ppm (0, 0.05, 0.1, 0.25 and 0.5%) JOC for two years. Mortality was increased in relation to dose with females dying earlier than males, in all the treated groups. All the 5000 ppm (0.5%) group were dead by 45 weeks, all the 2500 ppm (0.25%) group by 68 weeks and all the 1000 ppm (0.1%) group by 104 weeks. Three major gross abnormalities were observed: liver damage, fluid in the pleural and/or peritoneal cavity, and tumourous masses in the intestines. The intestinal tumours were leiomyosarcomas, which were malignant, highly pleomorphic, and highly anaplastic. These tumours occurred most frequently in the duodenum and appeared to have arisen from the musculature of the tunica propria of the mucosa. The incidence was 0 in the controls, three in females on 500 ppm (0.05%), five in males on 1000 ppm (0.1%), two in males on 2500 ppm (0.25%) and 0 on 5000 ppm (0.5%). The histopathological changes observed in the heart and liver with chronic administration of JOC were similar to those observed with ß-asarone. Cardiac atrophy was observed in both test and controls but was more severe in test animals. The severity in all four test groups was similar. Fatty degeneration and fatty infiltration were increased with doses of 1000 ppm (0.1%) and greater and cardiac thrombosis was observed only with these levels. Passive hyperaemia of the liver generally increased with dose for all four treatment levels. Hepatic nodular hyperplasia was more severe in the treated groups but the incidence was not dose-related. In males, the 2500 and 5000 ppm (0.25 and 0.5%) levels caused marked growth depression. With the lower doses weight gain was normal for the first 26 weeks, then decreased. After 68 weeks, there appeared to be a slight weight loss. In the females, growth depression was dose-related and considerable on the 1000, 2500 and 5000 ppm (0.1, 0.25 and 0.5%) levels. On the 500 ppm (0.05%) level, weight gain was normal during the first year and slightly depressed thereafter. Haematological values were similar in control and test animals (Taylor et al., 1967; Taylor, 1981). Groups of 25 male and 25 female rats were fed levels of 0, 50, 100 and 5000 ppm (0, 0.005, 0.01 and 0.5%) JOC for two years. The rats on the 5000 ppm (0.5%) level showed the elevated and early mortality, the heart and liver lesions observed with this level in the study described above. One leiomyosarcoma was also observed in a male on this level. Heart and liver changes with the 50 and 100 ppm (0.005 and 0.01%) levels were similar in severity to those observed in the controls and consistent with geriatric changes. No leiomyosarcomas were observed in the control, 50 or 100 ppm (0.005 and 0.01%) levels (Taylor, 1981). Groups of 25 male and 25 female rats were fed diets containing EOC at levels of 0.1, 0.5, 1.0 and 2.0% for two years. This study was evaluated independently by two pathologists. Both reported the finding of leiomyosarcomas and hepatocellular adenomas and adenocarcinomas on the 1.0 and 2.0% dose levels. Liver changes, identified by one pathologist as hepatocellular adenomas or adenomatoid hyperplasia and by the other as nodular hyperplasia also occurred on the 0.1 and 0.5% levels. Other hepatic changes observed were hyperaemia, necrosis, hepatocellular vacuolation, and biliary duct proliferation. In general, these changes increased in severity and incidence with dose, with the changes at 0.1% being similar to those in the controls or slightly increased. Heart changes, consisting of myocardial atrophy, fibrosis, fatty degeneration and fatty infiltration, increased with increasing dose. The myocardial atrophy and damage was considered sufficient to account for the passive hyperaemia and congestion seen in the liver and other organs (Taylor, 1981). The toxicity of calamus oil has been reviewed by Opdyke, 1977. Comments Only limited information is available on the metabolism of ß-asarone in the rat, and none for man. Short-term administration of ß-asarone to rats resulted in both hepatic and cardiac damage. These changes were much more severe following long-term administration of ß-asarone. In addition, tumourous masses were observed in the intestinal tract. The tumours were identified as leiomyosarcomas. Similar effects were observed following administration of oil of calamus, the severity of the effect being directly related to the ß-asarone content. Tumours were also reported in the liver. Low levels of ß-asarone are not mutagenic in the Ames test with and without activation, but high concentrations (5000 ppm (0.5%)) have been shown to be positive in this system following activation. EVALUATION No ADI allocated. REFERENCES Baxter, R. M., et al. (1960) Separation of the hypnotic-potentiating principles from the essential oil of Acorus calamus L. of Indian origin by liquid-gas chromatograph, Nature, 185, 466-467 Chopra, I. C., Khajuria, B. N. & Chopra, C. L. (1957) Antibacterial properties of volatile principles from Alpinia galanga and Acorus calamus, Antibiot. Chemotherap., 1, 378-383 Dandiya, P. C. & Cullumbine, H. (1959) Studies on Acorus calamus. III. Some pharmacological actions of the volatile oil, J. Pharmacol. Exptl. Therap., 125, 353-359 Dandiya, P. C., Cullumbine, H. & Sellers, E. A. (1959b) Studies on Acorns calamus. IV. Investigations on mechanism of action in mice, J. Pharmacol. Exptl. Therap., 126, 334-337 Dandiya, P. C. & Menon, M. K. (1963) Effects of asarone and beta-asarone on conditioned responses, fighting behavior and convulsions, Brit. J. Pharmacol., 29, 436-442 Dandiya, P. C. et al. (1959a) Studies on Acorns calamus. II. Investigation of volatile oil, J. Pharm. Pharmacol., 11, 163-168 Dhalla, N. S. & Bhattacharya, I. C. (1968) Further studies on neuro-pharmacological actions of acorns oil, Arch. Int. Pharmacodyn., 172, 356-365 Dhalla, N. S., Malhotra, C. L. & Sastry, M. S. (1961) Effects of Acorns oil in vitro on the respiration of rat brain, J. Pharm. Science, 50, 580-582 Hagan, E. C. et al. (1967) Food flavourings and compounds of related structure. II. Subacute and chronic toxicity, Fd. Cosmet. Toxicol., 5, 141-157 Hsia, M. R. S., Adamovics, J. A. & Kreamer, B. L. (1979) Microbial mutagenicity studies of insect growth regulators and other potential in Salmonella typhimurium, Chemosphere, 8, 521-529 Jenner, P.M. et al. (1964) Food flavouring and compounds of related structure. I. Acute oral toxicity, Fd. Cosmet. Toxicol., 2 327-343 Larry, D. (1973) Gas-liquid chromatographic determination of beta-asarone, a component of oil of calamus, in flavors and beverages, Journal of the AOAC, 56, 1281-1283 Madan, B. R., Arora, R. B. & Kapila, K. (1960) Anticonvulsant, anti-veratrinic and antiarrhythmic actions of Acorus calamus Linn - an Indian indigenous drug, Arch. Int. Pharmacodyn., 124, 201-211 Malhotra, C. L., Das, P. K. & Dhalla, N. S. (1962) Investigations on the mechanism of potentiation of barbiturate hypnosis by hersaponin, acorus oil, reserpine and chlorpromazine, Arch. Int. Pharmacodyn., 138, 537-547 Malhotra, C. L. et al. (1961) Effect of hersaponin and acorus oil on noradrenaline and 5-hydroxytryptamine content of rat brain, J. Pharm. Pharmacol., 13, 447 Opdyke, D. L. J. (1977) Fragrance raw materials monographs: calamus oil, Fd. Cosmet. Toxicol., 15, 623-626 Oswald, O. E., Fishbein, L. & Corbett, B. J. (1969) Metabolism of naturally occurring propenylbenzene derivatives. I. Chromatographic separation of ninhydrin-positive materials of rat urine, J. Chromatog., 45, 437-445 Oswald, E. O. et al. (1971) Identification of tertiary aminomethylenedioxy-propiophenones as urinary metabolites of safrole in the rat, Biochim. Biophys. Acta., 230, 230-247 Sexana, B. P. et al. (1977) A new insect chemosterilant isolated from Acorus calamus L., Nature, 270, 512-513 Seto, T. A. & Keup, W. (1969) Effects of alkylmethoxybenzene and alkylmethylenedioxybenzene essential oils on pentobarbital and ethanol sleeping time, Arch. Int. Pharmacodyn., 180, 232-240 Taylor, J. M. (1981) (Food and Drug Administration) Personal communication to the World Health Organization concerning unpublished studies on beta-asarone and calamus oils. (1) Short-term study comparing toxicity of Jammu, European and Kashimir calamus oils. Performed 1966-1967. Pathology reports by William S. Monlux (May 1978) entitled "Comparison of microscopic lesions occurring in rats gavaged with Jammu, European and Kashmir varieties of oil of calamus" and "Comparison of microscopic lesions occurring in rats fed Jammu, European and Kashmir varieties of oil of calamus". (2) Long-term study Of beta-asarone. Performed 1967-1969. (a) Pathology report by William S. Monlux (August 1978) entitled "Microscopic lesions occurring in one hundred and ninety-four rats fed beta-asarone in their diet for twenty-four months" (This report indicates that a level of 2500 ppm beta-asarone was fed in the study; this group received Jammu oil of calamus not beta-asarone.) (b) Memo from Robert T. Habermann to Jean Taylor (16 June 1971) entitled "Carcinogenicity of beta-asarone in rats in a two-year feeding study". (Histopathological findings on 0, 400, 800, and 2000 ppm of beta-asarone in a two-year feeding study with Osborne-Mendel rats and an additional group given a diet containing 2500 ppm Jammu Oil of Calamus.) (c) Memo from Jean M. Taylor to Damon Larry (15 October 1976) entitled "Chronic rat feeding studies on beta-asarone and European oil of calamus". (3) Long-term study of low levels of Jammu oil of calamus. Performed 1965-1967. (a) Pathology report by William S. Monlux (May 1978) entitled "Microscopic lesions occurring in fifty rats fed oil of calamus (Jammu) for twenty-four months". (b) Pathology report by William S. Monlux (May 1978) entitled "Lesions occurring in one hundred and forty-eight rats fed oil of calamus (Jammu) in their diet for twenty-four months". (The rats receiving 50 and 100 ppm levels described in this report and the rats receiving 0 and 5000 ppm oil of calamus (Jammu) described in the report 3(a) are from the low dose Jammu oil of calamus study. The rats receiving 0, 500, 1000, and 2500 ppm Jammu oil of calamus described in this report are from the high dose level study reported in Taylor et al., 1967). (4) Long-term study of European oil of calamus. Performed 1967-1969. (a) Pathology report by Donald A. Willigan (22 October 1971) entitled "Project 602 WR 1932: Histopathologic evaluation of tissue from rats following continuous dietary intake for 104 weeks of oil of calamus". (b) Pathology report by William S. Monlux (June 1978) entitled "Lesions occurring in one hundred and ninety-four rats fed oil of calamus (European) in their diet for twenty-four months". (c) Memo from Jean M. Taylor, to Damon Larry (15 October 1976) entitled "Chronic rat feeding studies on beta-asarone and European oil of calamus". Taylor, J. M. et al. (1967) Toxicity of oil of calamus (Jammus variety), Toxicol. Exptl. Pharmacol., 10, 405 Usseglio-Tomasset, L. (1966) Estratta Ind. Agr., 4, 3-13. (Cited in Larry, 1973), Journal of the AOAC, 56, 1281-1283) Vashist, V. N. & Handa, K. L. (1964) A chromatographic investigation of Indian calamus oils, Soap, Perfumery & Cosmetics, 37, 135-139 Von Shramlik, E. (1959) Uber die Giftigkeit und Vertraglichkeit von atherischen Olen, Pharmazie, 14, 435. (Cited in Opdyke, D. L. J. (1977), Fd. Cosmet. Toxicol., 15, 623-626 Weinberg, M. (1969) Studies conducted with Calamus. Unpublished report from Foster D. Snell, Inc. submitted to the World Health Organization by Comitato Per Lo Studio Delle Bevande Alcooliche Aromatizzate Yabiku, H. K. (1980) "Calamus oil - Toxicological aspects and their control in alcoholic beverages", M. S. Thesis, Sao Paulo, Brazil, Submitted to FAO/WHO
See Also: Toxicological Abbreviations