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Skin manifestations of poisoning
Published in Biju Vasudevan, Rajesh Verma, Dermatological Emergencies, 2019
Long-term exposure to silver and its compounds results in a distinctive condition known as argyria. It may be localized or generalized depending on the exposure type. Generalized argyria is a manifestation of long-term systemic absorption of silver affecting the skin, eyes, mucosa, nails, and internal organs such as the spleen and liver. But systemic symptoms and carcinogenicity are rare even after prolonged exposure. There is a typical blue-gray pigmentation with a bit of a shiny tinge with accentuation over the sun-exposed site. The pigmentation appears gradually over years and is often mistaken by the patient as tanning in the beginning. After absorption, silver binds to tissue proteins and is converted to metallic silver in the presence of light, which then further oxidizes to form silver sulfide and silver selenide, which are responsible for the blackish discoloration.
Metals
Published in Frank A. Barile, Barile’s Clinical Toxicology, 2019
Anirudh J. Chintalapati, Frank A. Barile
The mechanism of toxicity and the acute and chronic symptoms of silver exposure are not well documented due to limited animal and human studies. Argyria is the most significant consequence of excess exposure to Ag and its related compounds.
Cutaneous Phototoxicity
Published in Henry W. Lim, Nicholas A. Soter, Clinical Photomedicine, 2018
Argyria is caused by deposition of silver within tissues. It was more common when various forms of silver were used as medicinal agents but is still occasionally seen after occupational exposure (silver reclamation workers, silversmiths, silver mining, silver nitrate manufacturing) (31). The blue-to-slate gray apearance of the sun-exposed skin and lunulae of the nails is the most obvious clinical manifestation. Several studies have demonstrated that equivalent amounts of silver are deposited in both sun-exposed and non-sun-exposed skin sites. However, upon exposure to light, silver compounds undergo a photochemical conversion similar to that occurring during exposure of photographic film, thus accentuating the pigmentary abnormalities in sun-exposed sites (32). Silver also has a stimulatory effect on melanocytes, which is an additional mechanism by which hyperpigmentation occurs.
Distribution, metabolism, excretion, and toxicity of implanted silver: a review
Published in Drug and Chemical Toxicology, 2022
Niels Hadrup, Anoop K. Sharma, Nicklas R. Jacobsen, Katrin Loeschner
Argyria—the blue-gray discoloration of skin after substantial exposure levels of silver—is a consequence of deposition of silver granules. Localized argyria with granules containing silver, selenium and sulfur was seen in a 41-year-old woman, who 20 years previously had about 300 gold-coloured silver acupuncture needles permanently implanted (estimated dose: 1.4 g Ag = ∼20 mg Ag/kg bw). She also had deposits of pure gold intracellularly, and this so-called chrysiasis could have contributed to the abnormal pigmentation of her skin (Suzuki et al.1993). Localized argyria was reported after implantation of prostheses with 20 µm silver coating (estimated dose: 2 g/patient = ∼28 mg/kg bw). Argyria was proposed in seven of 32 patients who had prostheses implanted into their bones. These seven patients had a median time since the implantation of 26 months. Notably, no attempt was made to prove silver in the observed granules. The blood and tissue levels in patients with suspected argyria were not different from those with no argyria, 14 vs. 21 µg Ag/kg blood and 550 vs. 490 µg/kg tissue, respectively (Glehr et al.2013). The observed levels of silver in blood were lower after implantation than those observed after oral or dermal/mucosal exposures in humans (Hadrup and Lam 2014, Hadrup et al.2018), perhaps explaining why no cases of generalized argyria (covering other areas than those of exposure) have been reported after implantation.
Systemic argyria with severe anemia (hemoglobin 2.4 g/L)
Published in Baylor University Medical Center Proceedings, 2022
Nathan Chow, Kristen Fain, Jay Truitt, Cloyce Stetson
Argyria is a rare disease caused by the chronic usage of products with high silver content. Silver granules deposit in organs such as the skin, causing a blue-gray discoloration that is worse in sun-exposed areas because the silver deposits are reduced by light.1,2 Symptoms can present locally or systemically, depending on the method of use.3,4 Silver has historically been utilized for ailments such as epilepsy and infectious diseases. Today, silver is mainly used in homeopathic treatments not approved by the US Food and Drug Administration to boost the immune system and now is the most common cause of generalized argyria.1,3,5
Safety profile of silver sulfadiazine-bFGF-loaded hydrogel for partial thickness burn wounds
Published in Cutaneous and Ocular Toxicology, 2018
Srijita Chakrabarti, Johirul Islam, Hemanga Hazarika, Bhaskar Mazumder, Pakalapati Srinivas Raju, Pronobesh Chattopadhyay
The present investigation deals with acute dermal irritation, skin sensitization and acute dermal toxicity, and acute eye irritation study. The potential toxicity of silver salts is well documented in many previous literatures owing to their extensive use as a therapeutic agent16–20. It would be worth to note that though numerous investigations relating to the toxicity of silver salts have been reported; however, only a few observed toxicity posed by silver salts. For example, White et al.21 observed argyria and argyrosis (blue-gray discoloration of the skin and eyes, respectively) that seemed to bring about by the deposition of silver precipitates when dermally exposured to silver salts in sufficient quantities. But, there is no evidence to date for the ability of silver in any form to exert distinct toxicity in the immune, cardiovascular, nervous or reproductive system in humans22,23. Silver salts, irrespective of their route of absorption, are associated with minimal toxicity to humans, the manifestations of which are limited only to argyria. Since, the toxicity of silver is low, the benefit/risk ratio is especially favorable for moderate burns24. Although silver is shown to be very effective in burn care treatments and is generally regarded as safe, it is still important to check the toxicity of a newly developed formulation in animals before going for clinical trials. In addition, safety study is must for any pharmaceutical formulation and its ingredients pertaining to regulatory guidelines, because even a positive efficacy testing cannot help the formulation to accomplish further trial processes once it shows any signs of toxicity. Formulations especially designed to be applied topically therefore be ensured to free from any skin irritation, sensitization, and dermal toxicity. Furthermore, ocular irritation is warranted for topical formulations.