Thank you for your inquiry.
The way in which you phrased your inquiry, using "coloring agents" in a generic fashion, prompts an answer of "yes." But the final answer would depend on the specific agent(s) to which you refer as well as the type of reaction in question. That is, coloring agents, depending on the type of skin testing you are referring to, and the agent in particular, can be used to corroborate both delayed hypersensitivity reactions (contact dermatitis) as well as immediate hypersensitivity reactions (anaphylaxis). Therefore, when one speaks of skin testing to "coloring agents" in this regard, in a generic sense testing can be done.
As you can see from the abstracts copied below, contact dermatitis can occur to chemical coloring agents, and patch tests can be utilized to identify the culprit. However, I am not aware of immediate hypersensitivity skin testing being of value in this type of coloring agent.
Nonetheless, there are also natural (organic) coloring agents, the prototype of which is carmine. Immediate hypersensitivity skin tests can be used (see abstracts copied below) to test for such agents.
Thank you again for your inquiry and we hope this response is helpful to you.
Contact Dermatitis. 1981 Jan;7(1):1-4.
Patch test sensitization to D & C yellow No. 11 and simultaneous reaction to quinoline yellow.
Björkner B, Magnusson B.
The quinoline color D & C Yellow No. 11 was added to a standard test series. Of 88 patients tested with 1% in PEG, four showed unexplained positive test reactions. One patient had a "flare-up" reaction after 14 days. At rechallenge he reacted to a dilution down to 0.00001%. Simultaneous reaction with the chemically related commonly used food color Quinoline Yellow (E 104) suggests cross-sensitivity.
Contact Dermatitis. 1983 Jul;9(4):263-8.
Contact allergic reaction to D & C Yellow No. 11 and Quinoline Yellow.
Björkner B, Niklasson B.
D & C Yellow No. 11 and Quinoline Yellow belong to a group of quinophtalone dyes with a common basic structure. D & C Yellow No. 11 is used mostly in plastics, spirit lacquers, coloured smokes and cosmetics, but it is also increasingly used as a dye in soaps and shampoos. Quinoline Yellow is used for dyeing wool, silk and nylon in cases where good light fastness is not required, but is most commonly used as a drug and food colouring agent. A patient, extremely sensitive to D & C Yellow No. 11 with a positive patch test reaction down to 0.00001%, also reacted to Quinoline Yellow at a test concentration of 0.1%. To establish if any cross-reactivity occurs between the two compounds, a high pressure liquid chromatograph was used for analysis, purification and separation of the two colours. The patient was then patch tested with the two colours and the pure fraction of Quinoline Yellow. The test results confirm a true sensitivity to Quinoline Yellow and to D & C Yellow No. 11, and may indicate cross-reactivity between the colours.
Ann Allergy Asthma Immunol. 1997 Nov;79(5):415-9.
Popsicle-induced anaphylaxis due to carmine dye allergy.
Baldwin JL, Chou AH, Solomon WR.
Department of Internal Medicine, University of Michigan, Ann Arbor, USA.
Background: IgE-mediated hypersensitivity is a suggested mechanism to explain adverse reactions from carmine-containing products.
Objective: To describe a patient who experienced anaphylaxis after ingestion of a popsicle colored with carmine and to provide additional evidence that the adverse reaction was IgE-mediated.
Methods: The patient and her husband underwent skin prick tests to the popsicle and carmine. The patient also received skin prick tests and/or open oral challenge to each of the other components of the incriminated food. Topical application of cosmetics with and without carmine to the patient's forearm was also performed. To confirm carmine-specific IgE, a Prausnitz-Kustner (P-K) test was performed using the patient's husband as recipient. Twenty control subjects also were tested to carmine by skin prick test.
Results: The patient showed 4+ skin prick test responses to the popsicle and carmine. Skin prick tests and/or open oral challenge to each of the other components of the popsicle were negative. The patient's husband's and 20 control subjects' skin prick tests to carmine were negative as was the patient's husband's skin prick test to the popsicle. Skin prick test reactivity to the popsicle and carmine were successfully transferred to the patient's husband in P-K format. Cosmetics applied to the patient's forearm elicited no immediate response.
Conclusion: The positive skin prick tests to the popsicle and carmine and the successful (P-K) transfer of skin prick test reactivity support a carmine-specific, IgE-mediated mechanism in explaining our patient's popsicle-induced anaphylaxis.
Adv Food Nutr Res. 2001;43:195-216.
The role of natural color additives in food allergy.
Lucas CD, Hallagan JB, Taylor SL.
International Association of Color Manufacturers, 1620 I Street, NW, Suite 925, Washington, DC 20006, USA.
A critical evaluation of the available information demonstrates that reactions to natural color additives are rare. Studies of turmeric and carotenoid pigments administered in mixtures with other food colorings failed to definitely identify reactions to either color additive. For carotenoids, the one case report of an adverse reaction was not conclusive. An anaphylactic reaction to saffron does suggest an IgE-mediated reaction, but the high use of saffron as compared with this single report of an adverse reaction suggests that sensitivity to saffron is extremely rare. Numerous reports of reactions to grapes or grape products have been reported in the literature, but no reports of sensitivities to grape skin extract or grape color extract were found. In rare cases, annatto dye may provoke a severe, adverse reaction in individuals with an uncommon hypersensitivity, and may aggravate the symptoms of patients suffering from recurrent urticaria. In its long history of use, there has been only one reported case of anaphylaxis resulting from the ingestion of annatto. Studies designed to investigate the role of annatto in recurrent urticaria sufferers were limited due to the absence of double-blind challenge and placebo controls. A number of cases of adverse reactions to carmine following ingestion have been reported in the literature. These adverse reactions suggest an IgE-mediated hypersensitivity. In many of the reported cases, the cause of sensitization to carmine was topical exposure from the use of carmine-containing cosmetics or occupational exposure to carmine and not from ingestion of carmine-containing foods and beverages. Following sensitization, affected individuals would be sensitive to carmine and the amounts present in foods and beverages could elicit allergic reactions. It is not known whether all individuals with carmine sensitivity induced through topical use are sensitive to the ingestion of carmine in foods. However, reactions to carmine solely because of ingestion are likely to be exceedingly rare due to the low use levels of carmine in foods and beverages. Despite their widespread use in food products, few reports of allergic reactions following ingestion have been reported for the majority of natural color additives. It is concluded that the ingestion of natural color additives presents a very low risk of provoking adverse reactions.
Phil Lieberman, M.D.