And inorganic tin compounds

Tin and inorganic tin compounds are used in a variety of products and processes. Tin-niobium wires have interesting properties in the field of superconductive magnets which generate enormous field strengths but use almost no power. 

It has been reported that trialkyltin compounds such as tributyltin and triph-enyltin are metabohzed sequentially to dialkyltin, monoalkyltin, and inorganic tin compounds. Other studies focusing on the actual active form of the organotin indicate that only the original forms of the organotin compounds are found in the cancer cells, consistent, and that the active form of the tin is the original compound and not a metabolite. ... 

Toxicology. Inorganic tin and its compounds are generally of a low order of toxicity, largely because of the poor absorption and rapid excretion from the tissues of the metal (42—49). The acidity and alkalinity of their solutions make assessment of their parenteral toxicity difficult. The oral LD q values for selected inorganic tin compounds are Hsted in Table 2. It is estimated that the average U.S. daily intake of tin, which is mostly from processed foods, is 4 mg (see Food processing). 

The inorganic tin compound that has received the most study from a toxicological viewpoint is stannic oxide. Autopsies performed on workers in the tin mining and refining industry, who inhaled tin oxide dust for as long as 20 yr, disclosed no pulmonary fibrosis (57). Inhalation for long periods produces a benign, symptomless pneumoconiosis with no toxic systemic effects (58). 

Other studies of the toxicity of stannous fluoride, sodium pentafluorostannite, sodium pentachlorostannite, sodium chlorostannate, stannous sulfide [1314-95-0] stannous and stannic oxides, stannous pyrophosphate [15578-26 ] stannous tartrate [815-85-0] and other inorganic tin compounds are reviewed in References (dh—12. The OSHA TLV standard for inorganic tin compounds is two milligrams of inorganic tin compounds as tin per cubic meter of air averaged over an eight-hour work shift (47). 

Commercially available tin compounds having aimual production or gross sales of >2.3 metric tons or 5,000.00 are Hsted in References 194 and 195. Principal U.S. producers of inorganic tin compounds include M T Chemicals, Inc., Vulcan Materials Company, and Allied Corporation. M T Chemicals, Inc., is the largest U.S. producer of organotin compounds, followed by Carstab Corporation, Witco Chemical Corporation, and Cardinal Chemical Company minor producers are Interstab, Synthetic Products Company, Tenneco Chemicals Company, and Ferro Chemical Company... 

The price of tin chemicals depends to a large extent on the fluctuating price of tin. The 1982 prices and the CAS Registry Numbers for selected inorganic tin compounds and organotins are Hsted ia Table 13. 

Occupational Health Guidelinesfor Inorganic Tin Compounds as Tin), U.S. Department of Labor, Occupational Safety and Health Administration, Washington, D.C., Sept. 1978. 

In the EU, a total of 12 779 tonnes of inorganic tin in 2001 was used in the production of the various organotin compounds, as well as in the production of inorganic tin compounds. It should be further noted that the above tonnage applies only to butyltin and octyltin compounds methyltin compounds, while used in the EU, are produced only outside the EU and are imported. 

A chloroform solution of toxic tributyltin fluoride was placed in a round-bottomed flask equipped with a reflux condenser, and bromine (3 equiv per Bu3SnF) was added all at once. After the mixture was stirred for 2-3 days at room temperature, aqueous sodium thiosulfate was added until the brown color of bromine disappeared. The aqueous layer containing inorganic tin compounds.was disposed of in accordance with Prudent Practices for Disposal of Chemicals from Laboratories" National Academic Press Washington, DC, 1983. 

The generation and recovery of stannane, methyl-, dimethyl-, and trimethyl-stannane were studied in seawater. Average tin recoveries for the six samples analysed, to which were added 0.4-1.6 ig methyltin compounds and 3ng inorganic tin, ranged from 96 to 109%. Reanalysis of analysed samples shows that all methyltin and inorganic tin is removed in one analysis procedure. 

Inorganic Tin Compounds as Flame, Smoke, and Carbon Monoxide Suppressants for Synthetic Polymers... 

At the present time, inorganic tin compounds find a relatively small use in natural polymers, particularly as flame-resist treatments for woollen rugs and sheepskins (8,9). Although certain other metal derivatives have received more attention, there has been much interest recently in the potential use of tin chemicals as flame retardants and smoke suppressants for synthetic polymers (10). 

Hence, it is apparent that certain inorganic tin compounds are very effective flame retardants and smoke suppressants for halogenated polymer formulations. Since these additives are generally non-toxic, their potential use as partial or total replacements for existing commercial flame retardants, such as antimony trioxide, is thought to merit serious consideration. 

Tne effectiveness of inorganic tin compounds as flame and smoke retardants, both alone and in combination with inorganic fillers, in several halogen-free thermoplastic, thermosetting and elastomeric substrates, is currently under investigation at the ITRI. 

Certain inorganic tin compounds are effective flame-retardant synergists when incorporated at a 2.5% level into a 50% ATH-filled ethylene-acrylic rubber composition. Tin-containing elastomer formulations retain their flame-retardant superiority at environmental temperatures up to 250°C, and samples containing 2.5% ZnSn(0H)g do not sustain combustion in air at this temperature. 

Inorganic tin compounds, in particular, zinc hydroxystannate and zinc stannate, are effective fire retardants in a number of polymer systems. They appear to have advantages over certain existing commercial additives, namely ... 

The analytical response of inorganic and organic tin compounds of formula R SnX 4 was studied for direct hydride generation and measurement with a non-dispersive AFD (atomic fluorescense detector). Tributyltin and phenyltin compounds gave unsatisfactory results. This was corrected by warming the sample with a dilute Br2-HN03 solution37. 

Few clinical or epidemiological studies exist concerning inorganic tin intoxication primarily because inorganic tin(IV) compounds are poorly absorbed by mammals. The absorption from the gut for most compounds is less than 2%. However, when inorganic tin compounds are injected iv, they have a higher absorption and are usually stored in the bones with a half-life of approximately 400 days1. 

Hamasaki and coworkers87 investigated the genotoxicity of 14 organic tin compounds (methyl-, butyl- and phenyltins) and inorganic tin (SnCU) on Escherichia coli and on Bacillus subtilis. Dibutyltin dichloride, tributyltin chloride, tributyltin chloride, bis(tributyl-tin)oxide, dimethyltin dichloride and trimethyltin chloride were all found to be genotoxic. 

Lethal and sublethal effects of inorganic and organic tin compounds in ambient medium to selected species of aquatic organisms... 

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