Evaluation of potential genotoxicity of five food dyes using the somatic mutation and recombination test

In this study, different concentrations of five food dyes (amaranth, patent blue, carminic acid, indigotine and erythrosine) have been evaluated for genotoxicity in the Somatic Mutation and Recombination Test (SMART) of Drosophila melanogaster. Standard cross was used in the experiment. Larvae including two linked recessive wing hair mutations were chronically fed at different concentrations of the test compounds in standard Drosophila Instant Medium. Feeding ended with pupation of the surviving larvae. Wings of the emerging adult flies were scored for the presence of spots of mutant cells which can result from either somatic mutation or somatic recombination. For the evaluation of genotoxic effects, the frequencies of spots per wing in the treated series were compared to the control group, which was distilled water. The present study shows that carminic acid and indigotine demonstrated negative results while erythrosine demonstrated inconclusive results. In addition 25 mg mL(-1) concentration of patent blue and 12.5, 25 and 50 mg mL(-1) concentrations of amaranth demonstrated positive results in the SMART.

Carmine (E-120)-induced occupational asthma revisited

BACKGROUND

Occupational asthma (OA) caused by carmine (E-120) has been reported.

OBJECTIVE

We sought to evaluate the prevalence of sensitization and OA at a natural dye processing factory in which 2 workers had been given a diagnosis of carmine-induced OA 6 years previously.

METHODS

The 24 current employees and one worker who had recently left work because of asthma completed a questionnaire and underwent skin testing (carmine, cochineal, carminic acid, curcuma, annato, and chlorophyll), carmine IgE dot-blot analysis, and methacholine inhalation testing. Workers exhibiting positive occupational skin test responses, work-related asthma, or bronchial hyperresponsiveness underwent specific inhalation challenge and serial peak expiratory flow rate recording.

RESULTS

Positive skin test responses to carmine (41.7%), cochineal (29.2%), and carminic acid (4.2%) were observed. Carmine IgE dot-blot results were positive in 4 subjects. No difference in atopy or smoking was observed between occupationally sensitized and nonsensitized subjects. Among the 5 employees reporting work-related asthma, 2 had positive skin test responses, and 4 had bronchial hyperresponsiveness. Five subjects underwent specific inhalation challenges: 2 workers had early asthma responses to carmine and cochineal challenges, and the remaining subjects did not have suggestive peak expiratory flow recordings. The subject who had left his job was given a diagnosis of carmine-induced OA.

CONCLUSION

The prevalence of sensitization and OA caused by carmine was 41.6% and 8.3%, respectively. When the 3 workers who had left their jobs were included, the cumulative incidence of sensitization and OA was 48.1% and 18.5%, resembling the healthy worker effect. Prevention programs to establish the permissible levels of airborne allergen should be implemented.

Cytotoxicity of natural hydroxyanthraquinones: role of oxidative stress

In order to assess the role of oxidative stress in the cytotoxicity of natural hydroxyanthraquinones, we compared rhein, emodin, danthron, chrysophanol, and carminic acid, and a series of model quinones with available values of single-electron reduction midpoint potential at pH 7.0 (E(1)7), with respect to their reactivity in the single-electron enzymatic reduction, and their mammalian cell toxicity. The toxicity of model quinones to the bovine leukemia virus-transformed lamb kidney fibroblasts (line FLK), and HL-60, a human promyelocytic leukemia cell line, increased with an increase in their E(1)7. A close parallelism was found between the reactivity of hydroxyanthraquinones and model quinones with single-electron transferring flavoenzymes ferredoxin: NADP+ reductase and NADPH:cytochrome P450 reductase, and their cytotoxicity. This points to the importance of oxidative stress in the toxicity of hydroxyanthraquinones in these cell lines, which was further evidenced by the protective effects of desferrioxamine and the antioxidant N,N'-diphenyl-p-phenylene diamine, by the potentiating effects of 1,3-bis-(2-chloroethyl)-1-nitrosourea, and an increase in lipid peroxidation.

Reproductive and neurobehavioral effects of cochineal administered to mice in the diet

Mice were given the natural color additive cochineal in their food to provide dietary levels of 0 (control), 0.5, 1.0, and 2.0%, from five weeks of age in the F0 generation to nine weeks of age in the F1 generation, and selected reproductive and behavioral parameters were measured. Cochineal had few adverse effects on litter size, weight, or sex ratio. The average body weight of offspring during the lactation period was significantly decreased in higher-dosed groups of each sex. With regard to the neurobehavioral parameters, surface righting at postnatal day (PND) four was significantly affected in male offspring during the lactation period. Several parameters of movement activity in females were significantly different from controls at eight weeks of age in the F0 generation and at three weeks of age in the F1 generation. Multiple water T-maze performance of females was affected in treatment groups in the second trial at seven weeks of age in the F1 generation. The dose levels of cochineal in this study produced some adverse effects in reproductive and neurobehavioral parameters in mice.

Genotoxicity studies in vitro and in vivo on carminic acid (natural red 4)

The potential genotoxic activity of carminic acid (CAS no. 1260-17-9; EINECS no. 215-023-3; C.I. no. 75410), a component of natural red colouring products (cochineal: CAS no. 1343-78-8; EINECS no. 215-680-6; C.I. no. 75470), used in food, cosmetics and drugs, has been evaluated by means of a series of short-term tests in vitro and in vivo, namely Salmonella reverse mutation, chromosome aberrations and sister chromatid exchanges in vitro on Chinese hamster ovary cells, and the mouse micronucleus test. All studies have produced negative results. The data obtained strongly support the non-mutagenic/non-carcinogenic activity of this compound. Genotoxicity data previously obtained for carminic acid, concerning the induction of a series of other genetic endpoints in different test systems, have also been considered, as have recent findings that indicate lack of carcinogenic activity in the cochineal preparation containing 29.8% carminic acid.

Carcinogenicity study of cochineal in B6C3F1 mice

The carcinogenicity of cochineal, a red colouring used in food and other products, was studied in a 2-yr bioassay in B6C3F1 mice. Groups of 50-55 mice of each sex were given 0, 3 or 6% cochineal in the diet for 2 yr. Mice of all groups developed tumours including hepatocellular adenomas or carcinomas, pulmonary adenomas or adenocarcinomas and lymphomas or lymphatic leukaemias, and the incidences of these tumours were not significantly different in treated and control groups. The results indicate that cochineal lacks carcinogenicity in mice and are consistent with those of in vitro short-term assays of cochineal and of carminic acid, an active principle of cochineal.

Additional survey on genotoxicity of natural anthraquinones in the hepatocyte primary culture/DNA repair assay

Genotoxicity of fungal anthraquinones of islandicin, iridoskyrin and (-) rubroskyrin, and a colorant of insect origin, cochineal and its component, carminic acid, an anthraquinone, was examined in the hepatocyte primary culture/DNA repair test. The results were compared with that of versicolorin A, an anthraquinone with bisfuran ring, which had been proved to be genotoxic on this assay. All of these anthraquinones, differently from versicolorin A did not show clear response of DNA repair. The results suggest that these agents are not genotoxic carcinogens.

Chronic toxicity/carcinogenicity study of carmine of cochineal in the rat

Carmine was fed continuously to groups of 54 males and 54 females at dietary levels providing 50, 150 or 500 mg/kg body weight/day for up to 109 wk. As a control, groups of 90 males and 90 females were fed the basal diet for the same period. The rats were derived from parents fed the same dietary levels for 60 days before mating and throughout pregnancy and were thus potentially exposed in utero. There were no adverse effects upon survival, growth or intakes of food and water. No changes associated with treatment were found during the periodic measurement of haematology or renal function, or in the serum chemistry or organ weights at the end of the study. Tumour incidence was not affected, and variations in the distribution of the non-tumour pathology were not considered to be due to treatment. It was concluded that carmine administered to rats in utero and for up to 109 wk is not carcinogenic and that the no-untoward-effect level is 500 mg carmine/kg body weight/day.

Three-generation reproduction study on carmine of cochineal in the rat

Carmine was fed continuously to male and female rats over three generations at dietary concentrations that provided intakes of 50, 150 or 500 mg carmine/kg body weight/day. In adult animals of all generations there were no effects of treatment on body-weight gain, food and water intakes or fertility. At autopsy the weights and the gross and microscopic appearance of the organs were normal. In the teratological investigations, examination of the foetal skeletons of the F3 generation revealed a slightly more advanced stage of ossification in all treated groups compared to those of the control. Survival, growth and development of offspring were similar in each group apart from a slight delay in the time of tooth eruption in the 150- and 500-mg/kg groups of the first and second generations. This was not seen in the final generation. It is concluded that carmine had no untoward effects on the growth and fertility of adult rats, or on the ante- and postnatal development of their offspring when given continuously at doses of up to 500 mg/kg body weight/day in the diet throughout all phases of mating, gestation, lactation, weaning and adult life over three successive generations.

Teratogenicity and embryotoxicity study of carmine of cochineal in the rat

Groups of 30 mated female rats were given daily doses of 0, 200, 500 or 1000 mg carmine/kg body weight by oral intubation throughout pregnancy. A group of 17 similar animals was given a solution of chlorides to provide an intake of sodium, potassium and ammonium equal to that resulting from the highest dose level of carmine. There were no effects of carmine treatment on body weights, pregnancy rates, pre-implantation losses, the average numbers of live young, litter weights or foetal weights. The group given the highest dose of carmine and the cation control had increased numbers of implantations and post-implantation losses. The latter was considered to be due to an inability to maintain the increased numbers of implantations rather than to an embryotoxic effect. The foetuses showed no malformations and those from the carmine-treated rats tended to have a slightly more advanced degree of ossification of certain skeletal elements than foetuses of the control animals. On the basis of the results obtained it is considered that there were no untoward effects on embryo development in rats given oral doses of up to 1000 mg carmine/kg body weight/day throughout pregnancy.

Carminic acid-promoted oxygen radical damage to lipid and carbohydrate

The food colouring carminic acid redox cycles to produce free radicals. These radicals, in the presence of trace amounts of iron salts, readily damage membrane lipid and degrade the carbohydrate deoxyribose. Damage to membrane lipid appears to involve mainly organic oxygen radicals such as alkoxy and peroxy radicals, whereas that to deoxyribose implicates the hydroxyl radical formed in a Fenton-type reaction. Antioxidants and iron chelators prevent such damage.