Guest guest Posted October 11, 2003 Report Share Posted October 11, 2003 Here is why the fear-mongers excluded the animal experiments -- they indicate the situation is much subtler and more complex and, in fact, the research specifically incomplete as yet. from: http://www.inchem.org/documents/jecfa/jecmono/v042je08.htm INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY WORLD HEALTH ORGANIZATION SAFETY EVALUATION OF CERTAIN FOOD ADDITIVES WHO FOOD ADDITIVES SERIES: 42 Prepared by the Fifty-first meeting of the Joint FAO/WHO Expert Committee on Food Additives (JECFA) World Health Organization, Geneva, 1999 IPCS - International Programme on Chemical Safety CARRAGEENAN (addendum) First draft prepared by Dr J.B. Greig Department of Health, Skipton House, London, United Kingdom Explanation Biological data Biochemical aspects Absorption, distribution, and excretion Biotransformation Degradation in the gastrointestinal tract Fermentation in the large intestine Toxicological studies Acute toxicity Short-term studies of toxicity Long-term studies of toxicity and carcinogenicity Genotoxicity Reproductive and developmental toxicity Special studies Proliferation and tumour promotion Gastrointestinal tract Immune system Nutrient absorption Irritation and sensitization Observations in humans Comments Evaluation References 1. EXPLANATION Carrageenan is a sulfated polygalactan with an average relative molecular mass well above 100 kDa. It is derived from a number of seaweeds of the class Rhodophyceae. It has no nutritive value and is used in food preparation for its gelling, thickening, and emulsifying properties. Three main types of carrageenan are used commercially, which are known in the food industry as iota-, kappa-, and lambda-carrageenan. These names do not reflect definitive chemical structures but only general differences in the composition and degree of sulfation at specific locations in the polymer. Carrageenan was reviewed previously by the Committee at the thirteenth, seventeenth, and twenty-eighth meetings (Annex 1, references 19, 32, and 66). At the twenty-eighth meeting, an ADI 'not specified' was allocated on the basis of the results of a number of toxicological studies on carrageenans obtained from various seaweed sources. The studies included a three-generation study of reproductive toxicity, short-term and long-term studies of toxicity in rats at dietary concentrations up to 5%, and short- and long-term studies of toxicity in hamsters, guinea-pigs, and monkeys. In general, the only effect observed was soft stools or diarrhoea at high doses, except in two studies in which material identified as being iota-carrageenan was administered at 1% in the drinking-water or 5% in the diet and produced ulceration in the gastrointestinal tract of guinea-pigs. Although degraded carrageenans can produce this effect, they are not used as food additives. At the twenty-eighth meeting, the Committee specifically pointed out that degraded carrageenans and 'semi-refined carrageenan' (or 'processed Eucheuma seaweed') were not included in the specifications of the food-grade material. At its forty-fourth meeting, in reviewing the data on processed Eucheuma seaweed obtained from E. cottonii, the Committee requested that all data on carrageenan be reviewed in 1998, with particular attention to the identity of the source materials and the specifications of the products tested (Annex 1, reference 116). At the present meeting, the Committee considered studies published since the review at the twenty-eighth meeting and, for earlier studies, indicated the identity of the seaweed source and the type of carrageenan, when these could be identified. 2. BIOLOGICAL DATA 2.1 Biochemical aspects 2.1.1 Absorption, distribution, and excretion Rats As rats excrete dietary concentrations of 2-20% carrageenan (kappa/lambda from Chondrus crispus) quantitatively in the faeces, it has no direct nutritive value (Hawkins & Yaphe, 1965). In groups of five rats that received 0.5% native carrageenan (iota-carrageenan from E. spinosum) or 5% degraded carrageenan for 10 days, faecal excretion and weight gain were similar with the two polymers (Dewar & Maddy, 1970), and native carrageenan (kappa/lambda from C. crispus), untreated or heat-sterilized in milk, was quantitatively excreted in the faeces of rats (Tomarelli et al., 1974). No carrageenan was found in the livers of rats fed 25% native carrageenan (kappa/lambda from C. crispus or Iridaea crispata) in the diet for one month (Chen et al., 1981), of rats fed diets containing 1 or 5% carrageenan (kappa from Gigartina spp., iota from E. spinosum) (Coulston et al., 1975), or of rats fed diets containing 5% Chondrus crispus carrageenan (kappa/lambda) for 13 weeks (Pittman et al., 1976). No carrageenan was detected in the small or large intestine of rats fed 5% native carrageenan (iota from E. spinosum) (Grasso et al., 1973). Nicklin & Miller (1984) reported that orally administered carrageenan (type unidentified) of high relative molecular mass could penetrate the mucosal barrier of adult animals via transport by macrophages in Peyer's patches. Carrageenan did not affect the number or distribution of these cells; however, when antigen was administered systematically to carrageenan-fed rats, the antigen-specific antibody response was suppressed. This result suggested that carrageenan interferes with antigen processing by macrophages and thus mollifies normal immune function. Analysis of liver samples from rats fed 25% native carrageenan (kappa/lambda from C. crispus or C. iridaea) in the diet for one month showed that only the second was stored in the liver in two animals, as determined by the presence of gamma metachromatic reaction sites in the Kupffer cells (Chen et al., 1981). The results of an additional early study suggested that the kappa/lambda form of carrageenan, prepared by a non-standard procedure from either C. crispus or Gigartina stellata, is not significantly absorbed from the intestine of Wistar rats (Carey, 1958). Two new studies have been reported since the last review (Arakawa et al., 1988; Nicklin et al., 1988); however, in neither report is the identity given of the species from which the carrageenan originated, and in the latter study the form of carrageenan that was used is unclear (International Food Additives Council, 1997). In the first study, rats quantitatively excreted the carrageenan (kappa form) in the faeces, and it had the same gel filtration distribution pattern as that of the material administered. In the latter study, in male PVG strain rats given radiolabelled carrageenan (iota-form), there appeared to have been some uptake into the intestinal wall, Peyer's patches, mesenteric and caecal lymph nodes, and serum; however, the method used to radiolabel the carrageenan with tritium is questionable (International Food Additives Council, 1997). Guinea-pigs Feeding of guinea-pigs with native carrageenan (iota from E. spinosum) at 5% in the diet for 21-45 days resulted in the accumulation of 36-400 pg/g of caecal or colonic tissue. The carrageenan was contained in macrophages (Grasso et al., 1973). Food-grade carrageenan (kappa from C. crispus, lambda from C. crispus, iota from E. spinosum) administered to guinea-pigs as a 1% solution in drinking-water for two weeks was not retained in the caecum (Engster & Abraham, 1976). Rabbits It was reported in an abstract that carrageenan (type and species of origin unidentified) was present in the liver, stomach, and small intestine of newborn rabbits given 40 mg native carrageenan orally. Carrageenan was not detected in the cardiac or portal blood 4 h after treatment (Udall et al., 1981). Monkeys Rhesus monkeys given 1% native carrageenan (kappa/lambda from C. crispus) in drinking-water for 7-11 weeks, with a subsequent 11-week recovery period, showed no evidence of carrageenan storage (Abraham et al., 1972). In another study on rhesus monkeys, no tissue storage of carrageenan (kappa/lambda from C. crispus) was found when the monkeys were given 1% native carrageenan in the drinking-water for 10 weeks (Mankes & Abraham, 1975). Monkeys receiving daily doses of 500 mg/kg bw native carrageenan (kappa/lambda from C. crispus) for 15 months excreted 12 µg/ml urine. The concentration was reported to be at the limit of detection of the method (Pittman et al., 1976). Monkeys receiving 50, 200, or 500 mg/kg bw per day native carrageenan (kappa/lambda from C. crispus) orally for 7.5 years showed no evidence of storage in the liver or other organs (Abraham et al., 1983). 2.1.2 Biotransformation 2.1.2.1 Degradation in the gastrointestinal tract Although native carrageenan may be degraded in the gut, this possibility is probably of limited toxicological significance, since, if native carrageenan were sufficiently degraded to cause ulceration or tumour growth, this would have been detected in feeding studies. Since food-grade carrageenan does not have the same effects as degraded carrageenan, it is either not degraded, not degraded to the same molecular mass, or not degraded in the same way. It would appear that carrageenan is only partially degraded, that most of the degradation takes place in the stomach, and that this limited degradation has no effect on the wall of the stomach, where the pH is very low and acid hydrolysis undoubtedly occurs. When a kappa/lambda mixture (from an unidentified species) was incubated in simulated gastric juice at pH 1.2 and 37°C, breakdown of glycosidic linkages was less than 0.1% after 3 h (Stancioff & Renn, 1975). Breakdown of kappa-carrageenan (from an unidentified species) was about 15 times greater than that of the iota form; however, the conditions of hydrolysis (6 h at pH 1.0) were more drastic than those that occur normally in the stomach, and the pH would be expected to be considerably higher in a full stomach (Ekstrom & Kuivinen, 1983). There is no evidence that carrageenan is degraded on the lower gut. Incubation of a carrageenan solution with the caecal contents of rats for several hours at 37°C did not alter its viscosity, suggesting that the microbial flora of the rat gut cannot break down carrageenan (Grasso et al., 1973). Degradation of carrageenan by a large number of intestinal bacteria in vitro has been reported, but the carrageenan used (of an unidentified form from an unidentified species) contained 20% reducing sugar, which would give a positive result in the test method. Among the bacteria claimed to break down carrageenan were Klebsiella pneumonia and Escherichia coli; however, both these species can be grown on carrageenan gel (Epifanio et al., 1981). If these bacteria had been able to degrade carrageenan, they would have liquefied the gel medium on which they were grown (Ochuba & von Riesen, 1980). Breakdown of food-grade carrageenan (kappa-, lambda-, and kappa/lambda-carrageenan from C. crispus and of iota-carrageenan from E. spinosum) isolated from faeces of guinea-pigs, rats, and monkeys has been reported, but the site of breakdown was not reported. No intestinal lesions were associated with the breakdown. The molecular mass attained (40-50 kDa) was not as low as that of degraded carrageenan (10-20 kDa) (Pittman et al., 1976). One new study has been reported. The degradation of food-grade kappa- and iota-carrageenan was studied under physiologically realistic conditions in an artificial stomach. kappa-Carrageenan was not hydrolysed at pH 8 or under the severe conditions of pH 1.2 for 6 h, and the relative molecular mass remained at > 200 kDa, no more than 20% having a molecular mass of < 100 kDa. It was confirmed that iota-carrageenan is more resistant to degradation than the kappa form (Capron et al., 1996). The originating species were E. cottonii for kappa-carrageenan and E. spinosum for iota-carrageenan; however, this is not stated in the paper (International Food Additives Council, 1997). The greater stability of iota-carrageenan to degradation may reflect the conformation of the macromolecule in the medium used (Ekström et al. 1983; Ekström, 1985; International Food Additives Council, 1997). 2.1.2.2 Fermentation in the large intestine No evidence of fermentation was seen after incubation of rat caecal contents with iota-carrageenan from E. spinosum (Grasso et al., 1973). A study in female Wistar rats fed carrageenan (type and origin unidentified) as an inert polysaccharide does not provide quantitative measures of its degradability (Elsenhans et al., 1981). Feeding of three-week-old male Sprague-Dawley rats for four weeks with a diet containing 5% iota-carrageenan originating from E. spinosum (International Food Additives Council, 1997) resulted in a significant reduction in the bacterial population of the caecum, as assessed by bacterial counts and the activity of various caecal microbial enzymes; however, the weights of the caecal contents and the caecal wall were increased (Mallett et al., 1984). Similar effects were seen in mice and hamsters fed dietary iota-carrageenan (origin unidentified) (Mallett et al., 1985); however, in neither study was the degradation of carrageenan measured. On the basis of the rates of evolution of methane, hydrogen sulfide, and carbon dioxide from a slurry of mixed human faecal bacteria, carrageenan (origin and type unidentified) was ranked second to fourth in ease of degradation among 15 laxative fibres (Gibson et al., 1990). In a study of 154 bacterial species commonly found in the human colon, carrageenan (origin and type unidentified) was one of the polysaccharides most resistant to fermentation (Salyers et al., 1977). 2.2 Toxicological studies 2.2.1 Acute toxicity Not all the studies of acute toxicity summarized in earlier reviews of the Committee are included here, as sufficient details on dose, type of carrageenan, or seaweed source were not given. Informative studies are summarized in Table 1. Additional unpublished studies in which unspecified types of carrageenan derived from an unknown seaweed species were fed to dogs and rhesus monkeys at doses up to 3000 mg/kg bw per day for seven days were reviewed at the twenty-eighth meeting. Gross and histopathological changes were seen at the end of treatment, predominantly in the gastrointestinal tract (Annex 1, reference 66). 2.2.2 Short-term studies of toxicity Rats Groups of two male albino rats fed 0, 5, 10, or 20% kappa/lambda-carrageenan from C. crispus for 10 weeks grew well, except that 50% of those at the highest dose died (Nilson & Schaller, 1941). In groups of male and female rats fed 2, 5, 10, 15, or 20% kappa/lambda-carrageenan from C. crispus for periods of 23-143 days, the only adverse effect was reduced growth rates at dietary concentrations of 10-20% (Hawkins & Yaphe, 1965). No effects on appearance or behaviour were observed in male and female Osborne-Mendel or Sprague-Dawley rats fed 5% kappa/lambda- carrageenan from C. crispus for nine months. Bile-duct proliferation was seen in one male Osborne-Mendel rat, and reduction of the liver lobes and crenation of the margins in three females (Coulston et al., 1976). Groups of 12 male and 25 female Sprague-Dawley rats were fed a diet containing 4% processed, heat-sterilized kappa/lambda- carrageenan for six months. There was no effect on growth rate, and the caecum and colon were normal on gross and microscopic examination (Tomarelli et al., 1974). Table 1. Acute toxicity of carrageenan Carrageenan Species Sex Route LD50 Reference (mg/kg bw) Studies summarized at the seventeenth meeting of the Committee kappa/lambda Mouse M/F Oral 9150 ± Food & Drug Research from C. crispus 440 Laboratories (1971) NR Rat NR Intravenous > 10 Morard et al. (1964) kappa/lambda Rat M/F Oral 5400 ± Food & Drug Research from C. crispus 260 Laboratories (1971) kappa/lambda Hamster M/F Oral 6750 ± Food & Drug Research from C. crispus 570 Laboratories (1971) kappa/lambda Guinea-pig NR Intravenous > 10 Morard et al. (1964) from C. crispus lambda from Guinea-pig NR Intravenous < 1 Anderson & Soman C. crispus or (1966) G. pistallata kappa/lambda Rabbit M/F Oral 2640 ± Food & Drug Research from C. crispus 360 Laboratories (1971) kappa or lambda Rabbit NR Intravenous 1-20 Duncan (1965) from C. crispus (LD100) NR Rabbit NR Intravenous < 50 Morard et al. (1964) New studies iotaa Rat NR Oral > 5000 Weiner (1991) iotaa Rat NR Inhalation > 930 ± Weiner (1991) (4-h 74 mg/ m3 LC50) iotaa Rabbit NR Dermal > 2000 Weiner (1991) NR, not reported; M/F, male and female a Stated to be kappa/lambda- carrageenan from Gigartina radula (International Food Additives Council, 1997) Addition of 5% iota-carrageenan from E. spinosum to the diet of 10 male Wistar rats for 56 days resulted in slight diarrhoea (Grasso et al., 1973). Guinea-pigs Groups of 10 adult male albino guinea-pigs were given either water or a 1% solution of undegraded iota-carrageenan from E. spinosum. After 20 days, two of four treated animals had ulcerative lesions in the caecum, and the remaining six animals had lesions at 30 days. The control group remained healthy (Watt & Marcus, 1969). It was reported in a brief letter that 5% iota-carrageenan in the diet had the same effect (Sharratt et al., 1970). Administration of 5% iota-carrageenan from E. spinosum to seven female guinea-pigs in the diet for 56 days resulted in the formation of multiple pin-point caecal and colonic ulcerations (Grasso et al., 1973). Pigs Groups of three male and three female Danish Landrace pigs were fed 0, 50, 200, or 500 mg/kg bw per day of kappa-carrageenan from C. crispus for 83 days. No compound-related deaths were seen, and the behaviour, appearance, and feed intake of the animals remained normal. There were no significant changes in haematological, clinical chemical, or urinary parameters. Areas of infolding of the intact epithelium with infiltration of the lamina propria of the colonic mucosa by macrophages and lymphocytes were seen in one pig at 200 mg/kg bw per day and two at 500 mg/kg bw per day, but these effects were considered to be reversible (Poulsen, 1973). Monkeys Male and female rhesus monkeys were given drinking-water containing 1% kappa-carrageenan from C. crispus for 7-11 weeks. The animals remained in good health, and there was no evidence of any adverse effect. One female killed at seven weeks had a grossly normal gastrointestinal tract, but some capillary hyperaemia and mucosal oedema were observed microscopically. A male killed at 11 weeks had no microscopic abnormalities. Two males and two females were allowed an 11-week recovery period and were then given carrageenan at escalating oral doses of 50-1250 mg/kg bw per day for up to 12 weeks. No gross adverse effects were observed, and the microscopic changes were not attributed to carrageenan (Benitz et al., 1973). Male and female infant baboons were reared from birth to 112 days of age on infant formula containing 0, 1, or 5% kappa/lambda- carrageenan derived from C. crispus. No effect was seen on organ or body weights, characteristics of the urine and faeces, gross findings, haematological or clinical chemical variables, or the gross or microscopic appearance of the gastrointestinal tract (McGill et al., 1977). Groups of 10 male and 10 female Sprague-Dawley rats were fed 0 or 5% conventionally processed iota-carrageenan from E. spinosum and kappa-carrageenan from E. cottonii in the diet for periods of over 90 days. An additional 10 rats of each sex were assigned to a 28-day reversibility phase. The changes observed during the course of the study were attributed by the authors to intake of a diet with a lower nutritional value than the basal diet. The partial reversal of the caecal weight changes during the 28-day reversibility phase and the absence of histopathological changes would support this conclusion (Robbins, 1997) 2.2.3 Long-term studies of toxicity and carcinogenicity Mice Lifetime administration of kappa/lambda-carrageenan from C. crispus or G. mamillosa at concentrations of 0, 0.1, 5, 15, or 25% in the diet to groups of five male and five female mice of two unidentified strains had no adverse effect (Nilson & Wagner, 1959). Rats Lifetime administration of kappa/lambda-carrageenan from C. crispus or G. mamillosa at concentrations of 0, 0.1, 5, 15, or 25% in the diet to groups of five male and five female rats of two unidentified strains resulted in evidence of hepatic cirrhosis, only at the 25% concentration, with no effect on mortality (Nilson & Wagner, 1959). Groups of 30 male and 30 female MRC rats were fed 0.5, 2.5, or 5% kappa-carrageenan from C. crispus in the diet for life; 100 males and 100 females constituted the control group. Animals occasionally developed soft stool consistency, particularly near the start of the experiment. There was a statistically nonsignificant trend towards an increased incidence of benign mammary tumours and testicular neoplasms in the group fed 2.5% (Rustia et al., 1980). Groups of 15 male and female Sprague-Dawley rats were given extracts of kappa-carrageenan from Hypnea musciformis or Irideae crispata at a concentration of 1 or 5% in the diet for one year. Weight loss (p = 0.05) was observed in all treated rats as compared with the control group, which received alphacel. The livers of rats at 1% were normal on gross and microscopic examination. Gross and microscopic examinations of the livers of rats given 5% kappa-carrageenan from H. musciformis were normal, except for nodules in two of 12 livers. Gross observation of the livers of rats receiving 5% kappa-carrageenan from I. crispata showed decreased size, rough surface, and vascularization in 10/13 rats, which was probably related to treatment. Microscopically, these livers were normal, except for focal necrosis in 1 of 10 livers. There was no evidence of storage of carrageenan-like material (metachromatic) in the liver cells of any of the treated rats, and no fibrillar material was observed by electron microscopy. No changes were observed in the stools of rats receiving 1% of either carrageenan, but female rats given 5% kappa-carrageenan from I. crispata and males given either carrageenan at the 5% concentration had loose stools. Blood was found sporadically in the stools, but the frequency was not significant (Coulston et al., 1975). Monkeys Nineteen male and 21 female rhesus monkeys were fed 0, 50, 200, or 500 mg/kg bw kappa/lambda-carrageenan by gavage daily on six days a week for five years and carrageenan incorporated into the diet for a further 2.5 years. Loose stools, chronic intestinal disorders, poor appetite, and emaciation were seen in an apparently random distribution. Stool consistency was decreased in a dose-related trend over the entire 7.5 years of the study, and findings of faecal occult blood were increased in a similar fashion. Mean survival time was similar in all groups, and no gross or microscopic changes were detected in the tissues examined. Sporadic differences in body weight from controls were seen randomly; females had significant body-weight depression in the last 2.5 years of the study, which did not appear to be dose-related. No consistent, statistically significant changes occurred in haematological or clinical chemical values, absolute organ weights, or organ-to-body weight ratios after 7.5 years of feeding carrageenan. Cytochemical and ultrastructural observations revealed no storage of carrageenan-like material in livers obtained at biopsy or in other organs obtained at necropsy from monkeys given carrageenan, and no dose-related gross or microscopic changes in other tissues (Abraham et al., 1983). No new information was available. 2.2.4 Genotoxicity Assays for reverse mutation with kappa/lambda-carrageenan from C. crispus in Salmonella typhimurium strains TA1535, TA1537, and TA1538 and Saccharomyces cerevisiae strain D4 gave negative results (Brusick, 1975). The results of tests with kappa/lambda-carrageenan from C. crispus for cytogenetic changes in a host-mediated assay (Litton Bionetics, 1972) and for dominant lethal mutations in rats (Stanford Research Institute, 1972) were stated to be negative, but neither study would meet currently required standards. The reporting of an additional early study of kappa/lambda-carrageenan from C. crispusis inadequate (Mori et al., 1984), and some of the results of the most recent study (on what can be deduced to be a processed Eucheuma seaweed and its normally processed counterpart) are not consistent with current experience (Sylianco et al., 1993). 2.2.5 Reproductive and developmental toxicity Mice Groups of 22-27 pregnant CD-1 mice were given either the sodium (Food & Drug Research Labs., Inc., 1972a) or the calcium (Food & Drug Research Labs., Inc., 1972b) salt of kappa/lambda-carrageenan from C. crispus orally at doses of 0, 10, 45, 470, or 900 mg/kg bw per day on days 6-15 of gestation. The number of fetal resorptions and/or fetal deaths appeared to be increased, and there were dose-dependent decreases in the number of live pups and in pup weight; skeletal maturation was retarded (Food & Drug Research Labs., Inc., 1972a). Rats Groups of 21-27 pregnant rats were given either the sodium (Food & Drug Research Labs., Inc., 1972a) or the calcium (Food & Drug Research Labs., Inc., 1972b) salt of kappa/lambda-carrageenan from C. crispus at 0, 40, 100, 240, or 600 mg/ kg bw per day on days 6-15 of gestation. There was an apparent increase in the number of fetal resorptions, with no decrease in the number of live pups. At the highest dose, pup weight was decreased. A dose-dependent increase in the incidence of missing skeletal sternebrae was seen, with no other compound-related abnormalities (Food & Drug Research Labs., Inc., 1972a). Four groups of 21-24 pregnant rats were fed 1 or 5% sodium or calcium kappa/lambda-carrageenan from C. crispus on days 6-16 of gestation. Concurrent groups also received the basal (control) diet, and one group each received aspirin by stomach tube. All animals were killed on day 20, the uterine contents were examined, and the numbers of implants, resorptions, and live and dead fetuses and the average weight of the live pups in each litter were recorded. All fetuses were examined grossly for external abnormalities. There was no detectable effect on maternal or fetal survival, the rate of nidation, or the degree of maturation of fetuses, and neither material was teratogenic (Food & Drug Research Labs., Inc., 1973). In a three-generation study, groups of 40 male and 40 female Osborne-Mendel rats were fed diets containing the calcium salt of kappa/lambda-carrageenan at a concentration of 0.5, 1, 2.5, or 5%. After weaning, all animals were fed carrageenan in their diets for 12 weeks before mating. There was no dose-related effect on maternal weight gain. Carrageenan caused a significant, dose-related decrease in the weights of offspring at weaning but had no effect on fertility, average litter size, average number of liveborn animals, or the viability or survival of offspring. Diarrhoea was marked in animals fed the two highest doses. The average numbers of corpora lutea, implantations, and early or late deaths and the average percent resorptions per litter showed no dose-related change. Developmental effects were studied in the F2c and F3c litters. No specific external, skeletal, or soft-tissue anomaly could be correlated with dosage (Collins et al., 1977a,b). Sprague-Dawley rats were given a diet containing 0.45, 0.9, or 1.8% of the calcium salt of carrageenan for 14 days before mating, for 14 days during breeding, throughout gestation (22 days), lactation (21 days) and post-weaning (69 days, i.e. from weaning at 21 days of age until termination of the experiment at 90 days of age). Inconsistent effects were seen on reproduction and on the physical and behavioural development of the offspring, with no relationship to dose (Vorhees et al., 1979). Hamsters Groups of 23-30 pregnant hamsters were given either the sodium (Food & Drug Research Labs., Inc., 1972a) or the calcium (Food & Drug Research Labs., Inc., 1972b) salt of kappa/lambda-carrageenan from C. crispus at 0, 40, 100, 240, or 600 mg/ kg bw per day on days 6-10 of gestation. There was no significant effect on nidation or on maternal or fetal survival but some evidence for a dose-dependent delay in skeletal maturation (Food & Drug Research Labs., Inc., 1972a). Four groups of 21-26 pregnant hamsters were fed diets containing 1 or 5% sodium or calcium kappa/lambda-carrageenan from C. crispuson days 6-11 of gestation. Concurrent groups also received the basal diet, and one group of 25 animals received aspirin by stomach tube. All animals were killed on day 14, the uterine contents were examined, and the numbers of implants, resorptions, and live and dead fetuses and the average weight of the live pups in each litter were recorded. All fetuses were examined grossly for external abnormalities. There was no detectable effect on either maternal or fetal survival or on the degree of maturation of fetuses. The pregnancy rate of females fed 5% of the calcium salt was marginally but significantly reduced, but neither material was teratogenic (Food & Drug Research Labs., Inc., 1973). Randomly selected pregnant Syrian hamsters were intubated with the sodium or calcium salt of native carrageenan or with degraded carrageenan in distilled water at doses of 0, 10, 40, 100, or 200 mg/kg bw on days 6-10 of gestation. At least 21 pregnant females were examined at each dose of native carrageenan, but only eight were tested at each dose of degraded carrageenan as only a limited supply of this compound was available. The highest concentration tested was 200 mg/kg bw per day because the gelling capacity of the compounds precluded higher concentrations. The animals were killed on day 14. No dose-related teratogenic or fetotoxic effects were seen (Collins et al., 1979). Rabbits Groups of 12-13 pregnant rabbits were given either the sodium (Food & Drug Research Labs., Inc., 1972a) or the calcium (Food & Drug Research Labs., Inc., 1972b) salt of kappa/lambda-carrageenan from C. crispus at 0, 40, 100, 240, or 600 mg/ kg bw per day on days 6-18 of gestation. There was no clearly discernible effect on nidation or on maternal or fetal survival. The numbers of abnormalities of skeletal or soft tissue development did not differ from those in controls (Food & Drug Research Labs., Inc., 1972a). Chick embryos Before incubation, the yolk sacs of 240 chick eggs were injected with 0.1 mg of a sterile suspension of 0.1% lambda-carrageenan in 0.9% sodium chloride, while 240 control eggs were injected with 0.1 ml saline solution, and 240 eggs received no treatment. After mating, the following parameters were determined: mortality rate of embryos in which development was arrested, retardation of development based on body weight and length of the third toe and beak, and incidence of gross malformations. The mortality rate among embryos injected with carrageenan was significantly higher than those in the two control groups. Anomalies in the treated embryos were mainly located in the cephalic end, e.g. exencephaly, abnormal beak, and anophthalmia. All of the abnormal treated chicks showed two or more anomalies. The growth of newborn chicks from treated eggs was significantly retarded up to four days of age. Under these experimental conditions, lambda-carrageenan had teratogenic and lethal effects on chick embryos (Rovasio & Monis, 1980). At the twenty-eighth meeting of the Committee, studies of the effects of furcellaran, a product of Furcellaria species of seaweed, on chick embryos were considered. The reports cited were unpublished and are not currently available. Furcellaran was administered in water into the air cell or yolk sac of eggs before incubation (0 h) and after 96 h of incubation. Administration of furcelleran before incubation resulted in a curve with a slope that was not significantly different from zero, while administration at 96 h resulted in a line with a negative slope. No LD50 could be estimated from the regression lines. Furcellaran was injected in water into the albumen or the yolk before incubation (0 h) and after 96 h of incubation. Albumen was chosen instead of the usual air cell because the furcellaran solution formed globular coagulates as soon as it was injected into the air cell and could not be absorbed through the embryonic membrane. Furcelleran was embryotoxic under all conditions of the test. Probit analysis resulted in LD50 values of 1.6 mg/egg before incubation, 1.4 mg/egg at 96 h when given via the albumen, and 1.1 mg/egg before incubation; the slope of the curve was not significantly different from zero when furcellaran was injected into the yolk. When carrageenan was injected at a dose of 1 or 5 mg/egg into either the albumen or the yolk before incubation, anomalies of the eye and maxilla were seen which were nor observed in the solvent-treated embryos (Hwang & Connors, 1974). 2.2.6 Special studies 2.2.6.1 Proliferation and tumour promotion kappa/lambda-Carrageenan from Gigartina spp. administered at 5% in the diet to male Fischer 344 rats for four weeks increased the activity of colonic thymidine kinase, a marker of proliferation. Diets containing 5% guar gum or 10% wheat bran had no such effect (Calvert & Reicks, 1988). A dose-response relationship was seen for thymidine kinase activity, only the highest dose causing a statistically significant increase, when the concentration of carrageenan was 0, 0.65, 1.3, or 2.6%, meant to simulate 25, 50, and 100 times the maximal human intake. No histological abnormalities were seen at any dose (Calvert & Satchithanandam, 1992). A similar increase in colonic mucosal thymidine kinase activity was observed in groups of four Fischer 344 rats fed 5% iota-carrageenan for 28 or 91 days. When the animals were returned to basal diet after 28 or 64 days, the number of proliferating cells (identified by proliferating cell nuclear antigen immunohistochemistry) returned to normal and they were found in colonic crypts. No significant increase was seen in rats fed 0.5 or 1.5% iota-carrageenan (Wilcox et al., 1992). No aberrant crypt foci were found in nine female Fischer 344 rats fed a 10% gel of kappa-carrageenan instead of drinking-water for eight days (Corpet et al., 1997). Weanling female inbred Fischer 344 rats were fed semipurified diets containing 0 or 15% undegraded kappa/lambda-carrageenan. At seven weeks of age, all animals except controls were given azoxymethane subcutaneously at a dose of 8 mg/kg bw per week for 10 weeks or N-methyl- N-nitrosourea intrarectally at a dose of 2 mg per rat twice a week for three weeks. The rats given azoxymethane were autopsied at 40 weeks, and those given N-methyl- N-nitrosourea at 30 weeks after the first injection. No tumours were induced in the colon or in other organs of rats fed the control diet, but one untreated rat fed the carrageenan diet had a colon adenoma. The animals fed carrageenan and treated with azoxymethane or N-methyl- N-nitrosourea had a higher incidence of colorectal tumours (number of rats with colorectal tumours and number of tumours per tumour-bearing rat) than those fed the control diet and treated similarly. The undegraded carrageenan therefore enhanced the induced colorectal carcinogenesis (Watanabe et al., 1978). Seven-week-old male Fischer 344 rats were divided into two groups of 20 rats and two of 15 rats. kappa-Carrageenan (from an unspecified species) was administered to one group of 20 and one of 15 rats at 6% in the diet for 24 weeks. Both groups of 20 rats then received weekly subcutaneous injections of 1,2-dimethylhydrazine at 20 mg/kg bw for 16 weeks. Rats receiving both 1,2-dimethylhydrazine and carrageenan had a significantly greater number of colonic tumours per rat than those receiving 1,2-dimethyl-hydrazine alone. Additionally, the number of rats with tumours, the number of tumours in a more proximal location on the colon, and the overall size of the tumours were all increased (Arakawa et al., 1986). It was suggested that this promoter function might result from enhanced excretion of lithocholic acid (Arakawa et al., 1988). The ratio of N-acetylneuraminic acid to N-glycolyl-neuraminic acid was higher in the colonic tumours than in the surrounding tissue, but carrageenan had no effect on this ratio (Arakawa et al., 1989). Thirty five-week-old female Fischer 344 rats were injected intraperito-neally with azoxy-methane at 20 mg/kg bw to initiate colon cancer and were then divided into three groups. The controls were given water to drink, and the other two groups were given either a solution of 0.25% carrageenan (mainly kappa form) or a 2.5% gel. Promotion was assessed as the multiplicity of aberrant crypt foci after 100 days. This value was significantly increased in the group receiving carrageenan (Corpet et al., 1997). In a study described in an abstract, the promotion of microadenomas of the colon was compared in conventional rats given kappa-carrageenan from E. cottonii/G. radula as either 0.25% in the drinking-water or 2.5% as a gel in place of the drinking-water and in gnotobiotic rats that had been associated with intestinal microflora from human donors who had been 'adapted' to carrageenan. Azoxymethane-initiated microadenomas were promoted in the conventional rats rats fed carrageenan but not in the rats with human intestinal microflora (Millet et al., 1997). 2.2.6.2 Gastrointestinal tract Four of the citations in the report of the 1973 meeting of the Committee were unpublished and not available. One reference is to a letter with inadequate details which refers to an untraced article 'in press'. The report of Poulsen (1973) is mentioned above. In groups of 10 female Wistar rats fed 20% carrageenan (type and origin unspecified) or basal diet for four weeks, no effect was seen on the excretion of polyethylene glycol 4000, but the excretion of polyethylene glycol 900 was decreased and the length of the small intestinal was increased (Elsenhans & Caspary, 1989). 2.2.6.3 Immune system In most of the early studies of this system, the type and origin of the carrageenan was not specified in sufficient detail for it to be identified. Pretreatment of DA rat spleen cells with kappa/lambda-carrageenan from C. crispus inhibited their proliferative response to phytohaemagglutinin. Supernatants of macrophages incubated with 1-10 µg/ml of carrageenan were also inhibitory, whereas the same concentrations of carrageenan had no effect. Active secretion of a soluble inibitor was suggested, and some evidence that the mechanism might be prostaglandin-mediated was obtained (Bash & Cochrane, 1980). The effect of phytohaemagglutinin was tested in spleen and lymph-node cells of Lewis rats that had received a single oral dose of 0.5-50 mg kappa/lambda-carrageenan from C. crispus three days earlier. The proliferative responses were significantly suppressed at low doses but not at high doses. A similar effect was seen in offspring of DA rats that had been weaned onto 0, 0.1, or 1 mg/ml of carrageenan in the drinking-water. It was hypothesized that low doses of carrageenan in vivo and in vitro stimulate a population of macrophages that secretes an inhibitor of T lymphocyte proliferation (Bash & Vago, 1980). Spleen cells from weanling male DA Ag-B4 rats given boiled aqueous solutions of 5 or 50 mg/kg bw kappa/lambda-carrageenan from C. crispus by gavage on five days per week for four weeks showed long-lasting depression of mitogenesis stimulated by phytohaemagglutinin or concanavalin A. The maximal effect occurred with the low dose. There was also evidence of suppression of host resistance to Listeria monocytogenes (Cochran & Baxter, 1984). iota-Carrageenan from E. spinosum had a systemic adjuvant action in Brown Norway rats after intraperitoneal injection of 1 mg but not when given by gavage at 10 mg (Coste et al., 1989). Two types of iota-carrageenan from E. spinosum and one of kappa-carrageenan from C. crispus were fed at 5% in the diet to male Sprague-Dawley rats for 30 days. Although the concentration of immunoglobulin A antibodies in the bile was not significantly affected, the binding specificity for caecal bacteria was significantly enhanced by all three types of carrageenan (Mallett et al., 1985). Groups of 12 PVG male rats were given drinking-water containing 0.5% iota-carrageenan from E. spinosum, kappa-carrageenan from E. cottonii/C. crispus, or lambda-carrageenan from G. radula. Treatment did not alter local biliary or systemic antibody responses, but the anti-sheep red blood cell haemagglutinating antibody response was temporarily suppressed. kappa-Carrageenan was less effective than the other types (Nicklin & Miller, 1984). Groups of four male PVG rats were maintained on tap water containing 0 or 0.25% iota-carrageenan from E. spinosum. After 184 days of treatment, they were challenged intraperitoneally with sheep red blood cells, and their serum was analysed for antibody activity. The treated group had a delayed and significantly reduced antibody response (Nicklin et al., 1988). 2.2.6.4 Nutrient absorption Feeding of Fischer 344 rats on diets containing 15% kappa/lambda-carrageenan from G. radula had a cholesterol lowering effect (Reddy et al., 1980), but feeding of 5% kappa/lambda- carrageenan from C. crispus had no effect on growth rate or various parameters of nutrient absorption in rats (Tomarelli et al., 1974). Excretion of calcium, iron, zinc, copper, chromium, and cobalt was measured in weanling male Sprague-Dawley rats during an eight-day balance trial in which the animals were fed diets containing 0 or 10% kappa/lambda-carrageenan from C. crispus. Carrageenan significantly reduced the absorption of all minerals (Harmuth-Hoene & Schelenz, 1980). The extent of absorption of calcium by male Sprague-Dawley rats from radiolabelled calcium triphosphate or calcium chloride was unaffected by co-adminstration of 1% kappa/lambda-carrageenan from C. crispus (Koo et al., 1993). 2.2.6.5 Irritation and sensitization Food grade iota-carrageenan was not irritating to unwashed eyes of rabbits and was minimally irritating to washed eyes. It was not irritating to intact skin and was minimally irritating to abraded skin. It was not sensitizing to the skin of guinea-pigs (Weiner, 1991). 2.3 Observations in humans In none of the studies considered at the seventeenth meeting of the Committee was identification provided of the seaweed from which the carrageenan used in infant formulas originates. It has been stated, however, to be kappa/lambda-carrageenan (International Food Additives Council, 1997). Additionally, in none of the studies were comparisons made with controls of the effects on infants of the inclusion of carrageenan in infant formula. Co-administration of 20 g carrageenan (type and seaweed of origin unspecified) and 300 000 IU vitamin A to 11 women aged 19-22 years resulted in increased absorption of vitamin A (Kasper et al., 1979). Data from the United States National Maternal and Infant Health Survey indicate that a slightly higher proportion of infants who were fed liquid formula containing 0.03% kappa/lambda-carrageenan from an unknown species were free of upper respiratory tract infection during the first six months of life as compared with infants fed powdered, carrageenan-free formula. The odds ratio for the risk of one or more colds being reported during each month of the infant's first six months of life is 0.94 (95% confidence interval, 0.90-0.99; p = 0.015). The authors of the study concluded that carrageenan is not immunosuppressive; however, the Committee noted deficiencies in the study (Sherry et al., 1993). 3. COMMENTS Most of the toxicological studies in which an identifiable type of carrageenan and an identifiable seaweed species were used were undertaken with kappa- or kappa/lambda-carrageenan from C. crispus. The results of the few parallel studies suggest that there are no large differences in the effects of the different forms of carrageenan or in the effects of carrageenans prepared from different species of seaweed. The carrageenans are generally of high relative molecular mass and are not broken down to very small molecules in the gastrointestinal tract. At high levels of intake, these properties can cause adverse effects through their physical action on the gastrointestinal tract. Ulceration was observed previously in the gastrointestinal tract of guinea-pigs given high concentrations of iota-carrageenan. Similar findings were not reported in a recent well-conducted 90-day study in which rats were fed diets containing 5% conventionally processed iota-carrageenan from E. spinosum or kappa-carrageenan from E. cottonii. The changes that occurred, most notably an increase in the relative weight of the full and empty caecum, were considered to be the consequence of the accumulation of poorly absorbed material in the caecum and to be of no toxicological significance. The partial reversal of the caecal weight changes during the 28-day recovery phase of the study and the absence of histopathological changes support this conclusion. Studies of the carcinogenicity of carrageenan in rats have shown no effect. In addition, the results of assays for the genotoxicity of carrageenan have been negative. A proliferative response of the mucosa of the gastrointestinal tract of rats fed two forms of carrageenan at 2.6 or 5% of the diet has been reported; the response was reversible in the study in which 5% carrageenan was given. This response might explain the promotion of the action of known experimental colon carcinogens in rats given 2.5 or 6% of carrageenan. The Committee was aware of an abstract of a conference report which indicated that tumour promotion does not occur in rats in which the intestinal microflora are derived from human donors who have been 'adapted' to carrageenan. This would suggest that promotion of colon carcinogenesis in the rat is dependent on the presence of the normal microflora of the gastrointestinal tract. Early reports that carrageenan is present in parenteral tissues after dietary intake are probably unreliable. The presence of carrageenans in the macrophages in the walls of the caecum and colon may reflect the relative molecular mass distribution of the preparation used in the study. Maintenance of a restriction on the relative mass distribution in the specifications of carrageenan for food use provides protection against the adverse effects of carageenans of low relative molecular mass. There was evidence that carrageenan can affect the immune response of the gastrointestinal tract; however, no validated tests for assessing the nature and potential consequences of such an effect were available. A short communication relating to an epidemiological study did not indicate that carrageenan was immunotoxic in neonates receiving milk preparations containing carrageenan. 4. EVALUATION The Committee reiterated its previous statement that the ADI should not be considered applicable to neonates and young infants below the age of 12 weeks. The Committee extended the previous ADI 'not specified' to include processed Eucheuma seaweed in a group ADI 'not specified'. It expressed concern about the potential promotion of colon carcinogenesis by carrageenans and processed Eucheuma seaweed and therefore made the group ADI 'not specified' temporary, pending clarification of the significance of the promotion of colon cancer observed in experiments in rats. The Committee requires this information for review in 2001. 5. REFERENCES Abraham, R., Golberg, L. & Coulston, F. (1972) Uptake and storage of degraded carrageenan in lysosomes of reticuloendothelial cells of the rhesus monkey, Macaca mulatta. Exp. Mol. Pathol., 17, 77-93. Abraham, R., Benitz, K.-F., Mankes, R.F., Rosenblum, I. & Ringwood, N. (1983) Studies on rhesus monkeys (Macaca mulatta) receiving native carrageenan (Chondrus crispus) orally for 7.5 years. Book 1. Unpublished summary of final report from Institute of Experimental Pathology and Toxicology, Albany Medical College. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA and P. Couchoud, Marinalg, Paris, France. Anderson, W. & Soman, P.D. (1966) The absorption of carrageenans. J. Pharm. Pharmacol., 18, 825-827. Anonymous (1976) Unpublished report submitted to WHO at the twenty-eighth meeting of the Committee. Arakawa, S., Okumura, M., Yamada, S., Ito, M. & Tejima, S. (1986) Enhancing effect of carrageenan on the induction of rat colonic tumors by 1,2-dimethylhydrazine and its relation to ß-glucuronidase activities in feces and other tissues. J. Nutr. Sci. Vitaminol., 32, 481-485. Arakawa, S., Ito, M. & Tejima, S. (1988) Promoter function of carrageenan on development of colonic tumours induced by 1,2-dimethylhydrazine in rats. J. Nutr. Sci. Vitaminol., 34, 577-585. Arakawa, S., Wakazono, H., Ishihara, H. & Tejima, S. (1989) N-Acetylneuraminic acid and N-glycolylneuraminic acid in glycopeptides of colonic tumor and mucosa in rats treated with carrageenan and 1,2-dimethylhydrazine. Biochem. Biophys. Res. Commun., 159, 452-456. Bash, J.A. & Cochrane, F.R. (1980) Carrageenan-induced suppression of T lymphocyte proliferation in the rat: In vitro production of a suppressor factor by peritoneal macrophages. J. Reticuloendothel. Soc., 28, 203-211. Bash, J.A. & Vago, J.R. (1980) Carrageenan-induced suppression of T lymphocyte proliferation in the rat: In vivo suppression induced by oral administration. J. Reticuloendothel. Soc., 28, 213-221. Benitz, K.-F., Golberg, L. & Coulston, F. (1973) Intestinal effects of carrageenans in the rhesus monkey (Macaca mulatta). Food Cosmet. Toxicol., 11, 565-575. Brusick, D. (1975) Mutagenic evaluation of compound FDA 71-5. 977052-14-4 calcium carrageenan. Unpublished report from Litton Bionetics, Inc., Kensington, Maryland, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Calvert, R.J. & Reicks, M. (1988) Alterations in the colonic thymidine kinase enzyme activity induced by consumption of various dietary fibers. Proc. Soc. Exp. Biol. Med., 189, 45-51. Calvert, R.J. & Satchithanandam, S. (1992) Effects of graded levels of high-molecular-weight carrageenan on colonic mucosal thymidine kinase activity. Nutrition, 8, 252-257. Capron, I., Yvon, M. & Muller, G. (1996) In-vivo gastric stability of carrageenan. Food Hydrocolloids, 10, 239-244. Carey, P.L. (1958) The digestibility of polysaccharides by rats. Thesis, Purdue University. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Chen, J., Appleby, D.W., Weber, P. & Abraham, R. (1981) Detection of a carrageenan in rat liver homogenates after feeding in the diet (Abstract). Toxicologist, 1, 133. Cochran, F.R. & Baxter, C.S. (1984) Macrophage-mediated suppression of T lymphocyte proliferation induced by oral carrageenan administration. Immunology, 53, 291-297. Collins, T.F.X., Black, T.N. & Prew, J.H. (1977a) Long-term effects of calcium carrageenan in rats. I. Effects on reproduction. Food Cosmet. Toxicol., 15, 533-538. Collins, T.F.X., Black, T.N. & Prew, J.H. (1977b) Long-term effects of calcium carrageenan in rats. II. Effects of foetal development. Food Cosmet. Toxicol., 15, 539-545. Collins, T.F.X., Black, T.N. & Prew, J.H. (1979) Effects of calcium and sodium carrageenans and [iota]-carrageenan on hamster foetal developmemnt. Food Addit. Contam., 17, 443-449. Corpet, D.E., Taché, S. & Préclaire, M. (1997) Carrageenan given as a jelly, does not initiate, but promotes the growth of aberrant crypt foci in the rat colon. Cancer Lett., 114, 53-55. Coste, M., Dubuquoy, C. & Tomé, D. (1989) Effect of systemic and orally administered iota-carrageenan on ovalbumin-specific antibody response in the rat. Int. Arch. Allergy Appl. Immunol., 88, 474-476. Coulston, F., Golberg, L., Abraham, R., Benitz, K.-F. & Ford, W. (1975) Carrageenans (Hercules Incorporated). Safety evaluation. Nine month study. Unpublished interim progress report (March 1975) from Institute of Comparative and Human Toxicology, Center of Experimental Pathology and Toxicology, Albany Medical College, Albany, New York, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Coulston, F., Abraham, R., Benitz, K.-F. & Ford, W. (1976) Response of the livers of male and female rats (Osborn/Mendel and Sprague-Dawley) to Alphacel and a carrageenan (HMR) for nine months using two different basal diets. Nine month progress report (March 1976) from Institute of Comparative and Human Toxicology, Center of Experimental Pathology and Toxicology, Albany Medical College, Albany, New York, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Dewar, E.T. & Maddy, M.L. (1970) Faecal excretion of degraded and native carrageenan by the young rat. J. Pharm. Pharmacol., 22, 791-793. Duncan, J.G.C. (1965) Thesis, University of Glasgow, Scotland, United Kingdom Ekström, L.G. (1985) Molecular-weight-distribution and the behaviour of kappa-carrageenan on hydrolysis. Part II. Carbohydrate Res., 135, 283-289. Ekström, L.G. & Kuivinen, J. (1983) Molecular weight distribution and hydrolysis behaviour of carrageenans. Carbohydrate Res., 116, 89-94. Ekström, L.G., Kuivinen, J. & Johansson, G. (1983) Molecular weight distribution and hydrolysis behaviour of carrageenans. Carbohydrate Res., 116, 89-94. Elsenhans, B. & Caspary, W.F. (1989) Differential changes in the urinary excretion of two orally administered polyethylene glycol markers (PEG 900 and PEG 4000) in rats after feeding various carbohydrate gelling agents. J. Nutr., 119, 380-387. Elsenhans, B., Blume, R. & Caspary, W.F. (1981) Long-term feeding of unavailable carbohydrate gelling agents. Influence of dietary concentration and microbiological degradation on adaptive responses in the rat. Am. J. Clin. Nutr., 34, 1837-1848. Engster, M. & Abraham, R. (1976) Cecal response to different molecular weights and types of carrageenan in the guinea pig. Toxicol. Appl. Pharmacol., 38, 265-282. Epifanio, E.C., Veroy, R.L., Uyenco, F., Cajipe, G.J.B. & Laserna, E.C. (1981) Carageenan from Eucheuma spiratum in bacteriological media. Appl. Environ. Microbiol., 41, 155-163. Food and Drug Research Labs., Inc. (1971) Report on contract no. FDA 71-260 from Food and Drug Research Laboratories, Inc., Maspeth, New York, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Food and Drug Research Labs., Inc. (1972a) Teratologic evaluation of FDA 71-3 (sodium carragheenate) in mice, rats, hamsters and rabbits. Report number PB-221 812 from Food and Drug Research Laboratories, Inc., Maspeth, New York, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Food and Drug Research Labs., Inc. (1972b) Teratologic evaluation of FDA 71-5 (calcium carragheenate) in mice, rats, hamsters and rabbits. Report number PB-221 787 from Food and Drug Research Laboratories, Inc., Maspeth, New York, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Food and Drug Research Labs., Inc. (1973) Teratologic evaluation of carragheenan salts in rats and hamsters. Report from Food and Drug Research Laboratories, Inc., Waverly, New York, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Gibson, G.R., Macfarlane, S. & Cummings, J.H. (1990) The fermentability of polysaccharides by mixed human faecal bacteria in relation to their suitability as bulk-forming laxatives. Lett. Appl. Microbiol., 11, 251-254. Grasso, P., Sharratt, M., Carpanini, F.M.B. & Gangolli, S.D. (1973) Studies on carrageenan and large-bowel ulceration in mammals. Food Cosmet. Toxicol., 11, 555-564. Harmuth-Hoene, A.E. & Schelenz, R. (1980) Effect of dietary fiber on mineral absorption in growing rats. J. Nutr., 110, 1774-1784. Hawkins, W.W. & Yaphe, W. (1965) Carrageenan as a dietary constituent for the rat: Faecal excretion, nitrogen absorption, and growth. Can. J. Biochem., 43, 479-484. Hwang, U.K. & Connors, N.A. (1974) Investigation of the toxic and teratogenic effects of GRAS substances to the developing chicken embryo. Unpublished report from St Louis University School of Medicine, St Louis, Missouri, USA. Submitted to WHO by the US Food and Drug Administration, USA. International Food Additives Council (1997) Carrageenan. Unpublished monograph prepared by the International Food Additives Council, Washington DC. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Kasper, H., Rabast, U., Fassl, H. & Fehle, F. (1979) The effect of dietary fiber on the postprandial serum vitamin A concentration in man. Am. J. Clin. Nutr., 32, 1847-1849. Koo, J., Weaver, C.M. & Neylan, M.J. (1993) Solubility of calcium salts and carrageenan used in infant formulas did not influence calcium absorption in rats. J. Pediatr. Gastroenterol. Nutr., 17, 298-302. Litton Bionetics, Inc. (1972) Mutagenic evaluation of compound FDA 71-3. Sodium carrageenan. Unpublished report from Litton Bionetics, Inc., Kensington, Maryland, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Mallett, A.K., Wise, A. & Rowland, I.R. (1984) Hydrocolloid food additives and rat caecal microbial enzyme activities. Food Chem. Toxicol., 22, 415-418. Mallett, A.K., Rowland, I.R., Bearne, C.A. & Nicklin, S. (1985) Influence of dietary carrageenans on microbial biotransformation activities in the cecum of rodents and on gastrointestinal immune status in the rat. Toxicol. Appl. Pharmacol., 78, 377-385. Mankes, R. & Abraham, R. (1975) Lysosomal dysfunction in colonic submucosal macrophages of rhesus monkeys caused by degraded iota carrageenan. Proc. Soc. Exp. Biol. Med., 150, 166-170. McGill, H.C., Jr, McMahan, C.A., Wigodsky, H.S. & Sprinz, H. (1977) Carrageenan in formula and infant baboon development. Gastroenterology, 73, 512-517. Millet, A.-S., Verhaege, E., Préclaire, M., Taché, S. & Corpet, D. (1997) A food gelling agent, carrageenan K, promotes the growth of microadenomas of the colon in conventional rats but not in gnotobiotic rats with human flora (Abstract). In: Proceedings of the Fifth Symposium, Toulouse, Munich, 30 April-4 May 1997, p. 67 (in French). Morard, J.C., Fray, A., Abadie, A. & Robert, L. (1964) Nature of the renal lesions induced by intravenous injection of carrageenan. Nature, 202, 401-402. Mori, H., Ohbayashi, F., Hirono, I., Shimada, T. & Williams, G.M. (1984) Absence of genotoxicity of the carcinogenic sulfated polysaccharides carrageenan and dextran sulfate in mammalian DNA repair and bacterial mutagenicity assays. Nutr. Cancer, 6, 92-97. Nicklin, S. & Miller, K. (1984) Effect of orally administered food-grade carrageenans on antibody-mediated and cell-mediated immunity in the inbred rat. Food Chem. Toxicol., 22, 615-621. Nicklin, S., Baker, K. & Miller, K. (1988) Intestinal uptake of carrageenan: Distribution and effects on humoral immune competence. Adv. Exp. Med. Biol., 237, 813-820. Nilson, H.W. & Schaller, J.W. (1941) Nutritive value of agar and Irish moss. Food Res., 6, 461-469. Nilson, H.W. & Wagner, J.A. (1959) Feeding test with carrageenin. Food Res., 24, 235-239. Ochuba, G.U. & von Riesen, V.L. (1980) Fermentation of polysaccharides by Klebsiellae and other facultative bacteria. Appl. Environ. Microbiol., 39, 988-992. Pittman, K.A., Golberg, L. & Coulston, F. (1976) Carrageenan: The effect of molecular weight and polymer type on its uptake, excretion and degradation in animals. Food Cosmet. Toxicol., 14, 85-93. Poulsen, E. (1973) Short-term peroral toxicity of undegraded carrageenan in pigs. Food Cosmet. Toxicol., 11, 219-227. Reddy, B.S., Watanabe, K. & Sheinfil, A. (1980) Effect of dietary wheat bran, alfalfa, pectin, and carrageenan on plasma cholesterol and fecal bile acid and neutral sterol excretion in rats. J. Nutr., 110, 1247-1254. Robbins, M.C. (1997) A 90-day feeding study in the rat with semi-refined carrageenan from two sources, including a recovery phase. Unpublished report of project No. 3160/1/2/97 from BIBRA International, Carshalton, Surrey, United Kingdom. Submitted to WHO by Dr H.J. Bixler, Seaweed Industry Association of the Philippines, Searsport, Maine, USA. Rovasio, R.A. & Monis, B. (1980) Lethal and teratogenic effects of lambda-carrageenan, a food additive, on the development of the chick embryo. Toxicol. Pathol., 8, 14-19. Rustia, M., Shubik, P. & Patil, K. (1980) Lifespan carcinogenicity tests with native carrageenan in rats and hamsters. Cancer Lett., 11, 1-10. Salyers, A.A., West, S.E.H., Vercellotti, J.R. & Wilkins, T.D. (1977) Fermentation of mucins and plant polysaccharides by anaerobic bacteria from the human colon. Appl. Environ. Microbiol., 34, 529-533. Sharratt, M., Grasso, P., Carpanini, F. & Gangolli, S.D. (1970) Carrageenan ulceration as a model for human ulcerative colitis. Lancet, ii, 932. Sherry, B., Flewelling, A. & Smith, A.L. (1993) Carrageenan: An asset or a detriment in infant formula? Am. J. Clin. Nutr., 58, 715. Stancioff, D.J. & Renn, D.W. (1975) Physiological effects of carrageenan. Am. Cancer Soc. Symp. Ser., 15, 1-12. Stanford Research Institute (1972) Study of mutagenic effects of calcium carrogeenan (FDA No. 71-5). Unpublished report from Stanford Research Institute, Menlo Park, California, USA. Submitted to WHO by R.J.H. Gray, International Food Additives Council, Atlanta, Georgia, USA, and P. Couchoud, Marinalg, Paris, France. Sylianco, C.Y.L., Balboa, J., Serrame, E. & Guantes, E. (1993) Non-genotoxic and antigenotoxic activity of PNG carrageenan. Philipp. J. Sci., 122, 139-153. Tomarelli, R.M., Tucker, W.D., Jr, Bauman, L.M., Savini, S. & Weaber, J.R. (1974) Nutritional qualities of processed milk containing carrageenan. J. Agr. Food Chem., 22, 819-824. Udall, J.N., Harmatz, P., Vachino, G., Galdabini, J. & Walker, W.A. (1981) Intestinal transport and liver uptake of a food additive present in infant formulas (Abstract). Pediatr. Res., 15, 549. Vorhees, C.V., Butcher, R.E., Brunner, R.L. & Sobokta, T.J. (1979) A developmental test battery for neurobehavioral toxicity in rats: A preliminary analysis using monosodium glutamate, calcium carrageenan and hydroxyurea. Toxicol. Appl. Pharmacol., 50, 267-282. Watanabe, K., Reddy, B.S., Wong, C.Q. & Weisburger, J.H. (1978) Effect of dietary undegraded carrageenan on colon carcinogenesis in F344 rats treated with azoxymethane or methylnitrosourea. Cancer Res., 38, 4427-4430. Watt, J. & Marcus, R. (1969) Ulcerative colitis in the guinea-pig caused by seaweed extract. J. Pharm. Pharmacol., 21 (Suppl.), 187S-188S. Weiner, M.L. (1991) Toxicological properties of carrageenan. Agents Actions, 32, 46-51. Wilcox, D.K., Higgins, J. & Bertram, T.A. (1992) Colonic epithelial cell proliferation in a rat model of nongenotoxin-induced colonic neoplasia. Lab. Invest., 67, 405-411. See Also: Toxicological Abbreviations Carrageenan (JECFA Evaluation) Carrageenan (IARC Summary & Evaluation, Volume 31, 1983) Know your story before deciding how to tell it. --Everett Bedford, writer Quote Link to comment Share on other sites More sharing options...
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