| Gefahrenübersicht | Concentrated solutions can cause burns of the skin and eyes. A generalized argryia (silver discoloration of the skin and other organs) was reported in the past among workers heavily exposed to AgNo3 in manufacturing and photography. Methemoglobinemia was reported in the past after treatment of burn patients with 0.5% silver nitrate. [HSDB] Silver nitrate, used in burn therapy, is a reported inducer of methemoglobinemia. [ATSDR Case Studies, # 16] Used extensively in dressings soaked with 0.5% AgNO3 with no apparent toxicity[Nordberg, p. 1212] See NITRATES and NITRITES.The major hazards encountered in the use and handling of silver nitrate stem from its toxicologic properties. Toxic by all routes (ie, inhalation, ingestion, and dermal contact), exposure to this odorless, colorless-to-white, crystalline substance may occur from its use in silver-plating, in photography, in the manufacture of inks, paints, pigments, and dyes, as an analytical reagent and as an antiseptic. Effects from exposure may include contact burns to the skin, eyes, and mucous membranes, argyria (a blue-gray discoloration of skin), mild chronic bronchitis, and death from large ingested doses. The OSHA PEL is set at a TWA of 0.01 mg/cu m. Safe levels should be maintained by the use of engineering controls (eg, local exhaust ventilation, or process enclosure). In activities where over-exposure may occur, workers should wear impervious clothing, gloves, face protection, and a self-contained breathing apparatus. Such clothing and equipment should be removed before leaving the worksite. Skin that becomes contaminated with silver nitrate should be promptly washed. Eating and smoking should be prohibited in silver nitrate work areas. Silver nitrate is not expected to burn. However, if large quantities are involved in a fire, an explosion may result. Also, silver nitrate may form explosive compounds with sulfur, alcohols, and ammonia. If silver nitrate is involved in a fire, flood with water from as far away as possible (do not use dry chemical, CO2, or Halon). Silver nitrate should be stored in cool, dark areas, away from sources of physical damage, and ignition. Also, because it is an oxidizer, silver nitrate should be stored away from combustibles (eg, wood, paper, oil, fuels), and other substances with which it is incompatible (eg, halogenated acids and their salts, alkalies, antimony salts, arsenites, bromides, carbonates, chlorides, iodides, phosphates, and creosote). Silver nitrate may be shipped via air, rail, road, and water, in appropriate containers (substance may attack some forms of plastics, rubber, and coatings), bearing the label "Oxidizer". If silver nitrate spills, carefully shovel the material into a clean, dry covered container for later disposal or reclamation (solutions are first absorbed in vermiculite, dry sand, or earth). Large liquid spills on land first should be diked to prevent runoff from entering water sources or sewers, and then, if possible, contained in excavated pits or other holding areas that have been sealed with an impermeable flexible membrane liner. Solids should be covered with a plastic sheet. For spills of silver nitrate in bodies of water, apply sodium sulfide solution, then neutralize with agricultural lime, crushed limestone, or sodium bicarbonate, and use mechanical dredges to removed immobilized masses. Before implementing land disposal of silver nitrate waste, consult with environmental regulatory agencies for guidance. |
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