Gold in jewellery, cosmetics, pharmaceuticals and the food industry
Gold is a highly prized bullion that has been used to manifest magnificence and wealth since ancient times [1]. Many references to gold – as a symbol of earthly wealth – can be found in the Bible. This precious metal appears there, among other things, as one of the gifts brought to the newborn Jesus by the Three Kings.
Gold is not only a means of payment, a decorative material, and a jewelry raw material. It also plays a significant role in various industries, including electronics (construction of capacitors, electrodes, cables) and the food industry (cakes, alcoholic beverages, chocolates with gold flakes) [1,2,3]. Gold is used to produce, for example:
- Implants used, for example, in dentistry and microsurgery,
- Gold weights implanted in eyelids to address their insufficient closure,
- Vascular prostheses (stents) for patients with coronary artery disease [1,6].
Additionally, gold is an ingredient in many medicines and cosmetics. Nano gold (formed through the reduction of gold salts) is present in products used in skincare and anti-aging treatments [4]. Colloidal gold, on the other hand, is an excellent carrier for substances, facilitating their transport to the target cells of the body [1].
This metal has found broad applications in medicine, ranging from research techniques to medical diagnostics, genetic engineering, and the therapy of various disorders. Gold is utilized in the treatment of conditions such as cancer, rheumatoid arthritis, shingles, and acute asthma [1]. Currently, research is underway on its potential application in the therapy of individuals infected with the HIV virus [1].
Is it possible to be allergic to gold? Facts and doubts
The role of gold in the development of contact allergy has not yet been thoroughly investigated, nor has the mechanism of interaction of this metal with the skin [5]. The topic of gold allergy is controversial.
Some researchers emphasize that gold can trigger contact dermatitis only under specific clinical conditions – when ionization occurs [5,7]. The metal undergoes transformation into a form soluble by amino acids present in body fluids such as sweat. Only then can it be absorbed by the skin. However, metallic gold is difficult to dissolve, so the amount of released gold is rarely sufficient to induce an allergic reaction [5].
Before it was recognized that gold in jewelry items could cause allergies, cases of intolerance to medications containing this element were known [6]. Over time, an increasing number of people reported developing skin changes after contact with gold earrings and rings. Currently, it is known that the majority of individuals diagnosed with a gold allergy are women, likely because they use jewelry more frequently than men [5].
There are also reported cases of hypersensitivity in patients with dental gold supplements [6]. Additionally, it has been proven that contact allergy to gold often affects patients with stents. Gold-coated stents release ions into the surrounding tissues. Continuous release of ions can even lead to inflammation of the endothelium in the vessel where the stent is located [5].
Currently, there is no doubt that contact with gold can be associated with skin reactions. Gold reactions can be delayed (up to 3 weeks after contact) and persistent. However, this knowledge is relatively recent.
Old and new allergen
Gold was officially recognized as a significant contact allergen only in the 1990s when skin tests using gold salts began to be widely conducted [7]. Many cases of contact dermatitis in response to gold were described during that time [5]. This metal was even dubbed the Contact Allergen of the Year 2001 by the American Contact Dermatitis Society [5].
However, it quickly became evident that a positive patch test alone is not sufficient evidence for the presence of hypersensitivity. A significant portion of positive results was considered clinically insignificant [5]. Confirmation through a provocation test is necessary for diagnosing gold allergy [7]. Detecting gold allergy remains a significant diagnostic challenge [5].
Relevant in the context of allergy and its predisposition is the fact that gold can have different karats. Metal with a lower karat causes more intense skin reactions than the same metal in its pure form [5].
Gold contains impurities such as silver, copper, palladium, platinum, mercury, rhodium, iridium, and bismuth [9]. Allergic reactions, in some cases, may result from the presence of various metals in a given alloy. There is even a hypothesis that gold allergy may be a cross-reactivity in individuals allergic to other metals [5]. Sensitivity to this metal is statistically associated with allergic reactions to nickel and cobalt [10].
In addition, there are many factors that determine the reactivity of gold. These include pressure, friction and skin condition [5,7].
Allergy to gold – symptoms
Changes related to contact dermatitis caused by gold allergy most commonly affect the face (eyelids), ears, hands, or neck [5,10]. Prolonged exposure of an allergic individual to contact with gold may result in the formation of granulomas on the earlobes and numerous papular eruptions [4]. In some cases, these eruptions take the form of chronic lesions [5].
Among reactions to dental materials containing gold, various issues are listed, including inflammation of the lips, inflammation of the skin around the mouth, burning in the oral cavity, inflammation of the oral cavity, ulceration, and lichenoid reactions [5]. In a study conducted among patients with oral lichen planus, it was found that 20% of them had positive patch test results for gold [5].
The role of gold in the occurrence of systemic contact dermatitis (SCD) has also been confirmed. It has been demonstrated that intramuscular administration of gold (e.g., in the treatment of rheumatoid arthritis) can lead to a systemic reaction. Symptoms include fever, vomiting, tachycardia, erythema, petechiae on the trunk, limbs, face, mouth, and throat [5].
Moreover, occupational exposure has been identified among individuals who work in gold smelting or gilding porcelain using, among other things, gold hydroxide [5]. Workers in these occupations may experience various forms of skin inflammation. Other occupational groups exposed to contact with gold include jewelers, miners, dentists, and individuals involved in gold recycling [5].
Aleksandra Lipiec
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translation: Julia Majsiak
Date of publication: 5.01.2024
Date of update: 05.01.2026
