Silver in tissues

Silver concentrations in muscle of Antarctic birds were low (0.01 mg/kg DW) when compared to livers (0.02 to 0.46 mg/kg DW) or feces (0.18 mg/kg DW Szefer et al. 1993). Silver concentrations in avian tissues, especially in livers, were elevated in the vicinity of metals-contaminated areas and in diving ducks from the San Francisco Bay (Table 7.5). Birds with elevated concentrations of silver in tissues — as much as 44 mg/kg DW in liver in the common eider (Somateria mollissima) — seemed outwardly unaffected (Bryan and Langston 1992). 

The deposition of silver in tissues is the result of the precipitation of insoluble silver salts, such as silver chloride and silver phosphate. These insoluble silver salts appear to be transformed into soluble silver sulfide albuminates, to bind to or form complexes with amino or carboxyl groups in RNA, DNA, and proteins, or to be reduced to metallic silver by ascorbic acid or catecholamines (Danscher 1981). The blue or gray discoloration of skin exposed to ultraviolet light in humans with argyria may be caused by the photoreduction of silver chloride to metallic silver. The metallic silver is then oxidized by tissue and bound as black silver sulfide (Danscher 1981). Bucklet et al. (1965) identified silver particles deposited in the dermis of a woman with localized argyria as being composed of silver sulfide. 

CHRONIC HEALTH RISKS the dust of silver and its soluble compounds cause ar-gyria, the build-up of deposited silver in tissues, leading to gray-blue discoloration of eyes, skin, nasal septum, and throat may cause mild, chronic bronchitis necrosis of bone marrow, liver, and kidney may occur. 

Deposition of silver in tissues of warmblooded animals results from precipitation of relatively insoluble silver salts, such as silver chloride and silver phosphate. These insoluble salts may be transformed into soluble silver sulfide albuminates that bind or... 

CARIBOU, Rangifer tarandus Ratio of silver concentration (mg/kg FW) in tissues to silver concentration (mg/kg FW) in lichen diet ... 

Daskalakis, K.D. 1995. Silver in oyster soft tissue relations to site selection and sampling size, in A.W. Andren and T.W. Bober (organizers). Transport, Fate and Effects of Silver in the Environment. 3rd International Conference. August 6-9, 1995, Washington, DC. Univ. Wisconsin Sea Grant Inst., Madison, WI. 

A chloric acid digestion was used by Backer 2 391 for the preparation of tissue samples. The digest is simply diluted to determine iron, zinc, and copper. The tantalum sampling boat technique was used by Emmermann and Luecke 2531 to measure lead, zinc, and silver in prepared soil solutions. White 1S81 treated ashed plants with hydroxylamine in IN hydrochloric acid to reduce and dissolve oxides of manganese, prior to its determination by atomic absorption spectroscopy. 

Silver is some times released to the environment by the photographic industry, and is considered to be toxic at high concentration. Because of the evidence that silver, once absorbed, is held indefinitely in tissues, particularly the skin, without evident loss through usual channels of elimination or reduction by transmigration to other body sites, and because of other factors, the maximum amount of silver allowed in drinking water by the standard is 0.05 mg/L of water. 

During immersion, the maximum whole body silver concentration was 22.1 mg/kg DW vs. 0.8 in controls main sites of accumulation were the connecting tissues of nephridia and gut. No histopathology. A constant elimination of silver in urine occurs simultaneously with silver accumulation. During depuration, new connective tissue formed and silver concentrations were reduced by 88%... 

Danscher (1981) 7 Silver probe for gold detection in tissue sections... 

There are reliable and accurate ways of measuring silver in the body. Silver can be measured in the blood, urine, feces, and body tissues of exposed individuals. Because urine and blood samples are easy to get, these fluids are most often used to find out if a person has been exposed to silver in the last week or so. Silver builds up in the body, and the best way to learn if past exposure has occurred is to look for silver in samples of skin. Tests for silver are not commonly done at a doctor s office because they require special equipment. Although doctors can find out if a person has been exposed to silver by having blood or skin samples examined, they can not tell whether any health effects will occur. Information about tests for measuring silver in the body is in Chapters 2 and 6. 

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