This is all I have to hand James, http://risk.lsd.ornl.gov/tox/profiles/silver_f_V1.shtml
Toxicity Summary for SILVER 2. METABOLISM AND DISPOSITION 2.1. ABSORPTION Studies in humans and animals indicate that silver compounds are absorbed via the oral and inhalation routes of exposure, with some absorption occurring through both intact and damaged skin (ATSDR, 1990). East et al. (1980) reported that a patient with argyria (gray or blue-gray discoloration of the skin) absorbed approximately 18% of a single dose of orally administered silver. Generalized argyria in a woman who repeatedly applied a silver nitrate solution to her gums indicates absorption across the oral mucosa (Marshall and Schneider, 1977). Absorption from the lung was documented in a case of accidental exposure to radiolabeled silver metal dust (Newton and Holmes, 1966). Following intratracheal administration to beagle dogs, the absorption of metallic silver particles appears to be extensive. Phalen and Morrow (1973) estimated that up to 90% of silver (mean aerodynamic diameter = 0.5 µm) deposited in the lungs of dogs was absorbed into the systemic circulation 6 hours after exposure. In humans, less than 1% of dermally applied silver compounds are absorbed through the skin (Snyder et al., 1975). 2.2. DISTRIBUTION Silver has been detected in 50% of the samples of 29 human tissues, but at lower levels than other trace elements (U.S. EPA, 1985). Silver has no known physiological function in man, but its accumulation leads to argyria when the body burden is > 1 g (Stokinger, 1981). Granular deposits that contain silver have been observed in both pigmented and unpigmented skin of silver-exposed humans and animals. Once absorbed, orally-administered silver undergoes a first-pass effect through the liver, resulting in excretion into the bile, and thereby reducing the systemic distribution to tissues (ATSDR, 1990). Following ingestion of silver nitrate and silver chloride, silver was distributed widely in tissues of rats, with high concentrations seen in the tissues of the reticuloendothelial system (liver, spleen, bone marrow, lymph nodes, skin, and kidney) (Olcott, 1948). Silver was confined mainly to the liver of a worker who had accidentally inhaled radiolabeled silver metal; a biological half-life of 52 days was estimated (Newton and Holmes, 1966). Six hours after intratracheal administration of metallic silver to dogs, 96.9, 2.4, and 0.35% of the initially deposited dose was detected in the lungs, liver, and blood, respectively. The remaining silver was detected in the gall bladder and bile, intestines, and stomach. After 225 days, the distribution in tissue type was similar, with most of the silver found in the liver (Phalen and Morrow, 1976). 2.3. METABOLISM ATSDR (1990) reports that 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 are then transformed into soluble silver sulfide albuminates, to bind or to form complexes with amino or carboxyl groups in RNA, DNA, and proteins, or to be reduced by ascorbic acid or catecholamines. The skin discoloration of humans with argyria may be caused by a photoreduction of silver chloride to metallic silver. The metallic silver is then oxidized by tissue, subsequently forming black silver sulfide. 2.4. EXCRETION Following oral or inhalation exposure to silver compounds, humans excrete silver primarily in the feces and only very minor amounts in the urine (East et al., 1980; Newton and Holmes, 1966). In rats and mice, the cumulative recovery of silver in the feces was 98-99% on the second day after oral exposure to silver; monkeys excreted 94% (U.S. EPA, 1985). Dogs excreted approximately 90% of an inhaled dose of metallic silver particles in the feces within 30 days of exposure (Phalen and Morrow, 1973). ----- Original Message ----- From: "James Osbourne, Holmes" <a...@trail.com> To: "'Silver List'" <silver-list@eskimo.com> Sent: Thursday, 6 April 2000 17:15 Subject: CS>Absorbtion of CS > > Hello Folks, > > Does anyone have any studies on where and at what rate silver is absorbed in the human? Animal studies? > > Particular emphasis: 1. How much gets to intestine and alters flora? > 2. Can CS cause constipation? > > Any information will be appreciated. > > James Osbourne Holmes > a...@trail.com > > -- The silver-list is a moderated forum for discussion of colloidal silver. To join or quit silver-list or silver-digest send an e-mail message to: silver-list-requ...@eskimo.com -or- silver-digest-requ...@eskimo.com with the word subscribe or unsubscribe in the SUBJECT line. To post, address your message to: silver-list@eskimo.com Silver-list archive: http://escribe.com/health/thesilverlist/index.html List maintainer: Mike Devour <mdev...@id.net>
