Lead arsenates

Lead oxide is used in producing fine "crystal glass" and "flint glass" of a high index of refraction for achromatic lenses. The nitrate and the acetate are soluble salts. Lead salts such as lead arsenate have been used as insecticides, but their use in recent years has been practically eliminated in favor of less harmful organic compounds. 

Rotenoids. The use of rotenone-bearing roots as insecticides in the United States was developed as a result of federal laws against residues of lead, arsenic, and fluorine upon edible produce. Rotenone [83-79-4] (5) is harmless to plants, highly toxic to many insects, and relatively innocuous to... 

Tia is also used as an ahoyiag element ia lead—antimony alloys to improve fluidity and to prevent drossiag, ia lead—calcium alloys to improve mechanical properties and enhance electrochemical performance, ia lead—arsenic alloys to maintain a stable composition, and as an additive to low melting alloys. 

Lead—tin (1.8—2.5 wt %) is used both as a cable sheathing ahoy (BS 801 ahoy A and DIN 17640) and as a battery connector ahoy ia sealed lead—calcium—tin batteries (15). Tia is generahy added to lead—arsenic cable ahoys ia smah amounts. The arsenic ahoys have excehent creep resistance and mechanical properties, but are unstable and lose arsenic readily by oxidation. The addition of smah amounts of tin (0.10—0.20 wt %) eliminates arsenic loss. Lead ahoys having 0.4 wt % tin and 0.15 % cadmium, which are used for cable sheathing, do not age harden, show excehent corrosion and creep resistance, and are very ductile. 

Lead—antimony or lead—arsenic ahoys must not be mixed with lead—calcium (aluminum) ahoys in the molten state. Addition of lead—calcium—aluminum ahoys to lead—antimony ahoys results in reaction of calcium or aluminum with the antimony and arsenic to form arsenides and antimonides. The dross containing the arsenides and antimonides floats to the surface of the molten lead ahoy and may generate poisonous arsine or stibine if it becomes wet. Care must be taken to prevent mixing of calcium and antimony ahoys and to ensure proper handling of drosses. 

Other salts include lead arsenates and lead arsenites (see Insect control technology), lead chromates and lead sihcochromates (see Pigments), lead cyanide (see Cyanides), lead 2-ethyIhexanoate (see Driers and metallic soaps), and lead fluoroborate (see Fluorine compounds, inorganic). 

Monosodium methanearsonate (MSMA) [2163-80-6] CH AsONaOOH, disodium methanearsonate (DSMA) [144-21-8], CH2AsO(NaO)2, cacodyhc acid [75-60-5], (CH2)2AsOOH, and arsenic acid [7778-39-4], H AsO, are used ia agriculture appHcations (11,12). MSMA, DMSA, and cacodyUc acid are used as herbicides (qv) especially ia cotton (qv) fields for the control of Johnson and nutsedge grass and other weeds. Arsenic acid (13) and cacodyhc acid may be used as a desiccant for the defoHation of the cotton boU prior to harvesting. Calcium arsenate [7778-44-1], Ca2(As0 2> once an important chemical for the control of the boU weevil and cotton worm, has disappeared from appHcation and the use of lead arsenate [7784-40-9], Pb AsO, for fmit crops is currentiy restricted. 

Lead, arsenic, and antimony—determined in the solution obtained by boiling 10 g of the titanium dioxide for 15 min in 50 mL of 0.5 Nhydrochloric acid In addition to individual specifications, general specifications have been written for provisionally Hsted certifiable colors ... 

Cellulose acetate Silica gel Scoured wool Sawdust Rayon waste Fluorspar Tapioca Breakfast food Asbestos fiber Cotton linters Rayon staple Starch Aluminum hydrate Kaolin Cryolite Lead arsenate Cornstarch Cellulose acetate Dye intermediates Calcium carbonate White lead Lithopone Titanium dioxide Magnesium carbonate Aluminum stearate Zinc stearate Lithopone Zinc yellow Calcium carbonate Magnesium carbonate Soap flakes Soda ash Cornstarch Synthetic rubber... 

Lead arsenate 72 B36R Zinc oxide, heavy. 30-.35 A36Z5... 

A material that has a high toxicity does not necessarily present a severe toxic hazard. For example, a ton of lead arsenate spilled in a busy street is unhkely to poison members of the public just a short distance from the spiU, because it is not mobile. It could be carefully recovered and removed and would present a low risk to the gener pubhc, even though it is extremely toxic. On the other hand, a ton of liquefied chlorine spilled on the same street could become about 11,000 fF of pure gas. The IDLH for chlorine is 25 ppm. This is a concentration such that immediate action is required. Thus, the one ton of chlorine, if mixed uniformly with air, could create a cloud of considerable concern, having a volume of about 4.4 X 10 fF or a sphere 770 ft in diameter. This could quickly spread over downwind areas and... 

Chemical Designations - Synonyms Lead arsenate, acid Plumbous arsenate Chemical Formula PbHAS04. 

Latin American Crop Protection Association (LACPA), 259 Latvian histihite of Organic Synthesis (OIS), 262 Latvian Ministry of Eiivironmental Protection and Regional Development, 283 Laurel Industries Inc., 236, 241 Laxnii Organic hidustries Ltd., 173 Lead - metallic and inorganic compomids, 82 Lead acetate, 82 Lead arsenate, 82 Lead chloride, 82... 

Blei, n. lead, -abgang, m. lead dross, lead scoria, -ablagerung,/. lead deposit, -acetat, n. lead acetate, -ader, /. lead vein, -anti-monerz, n., -antimonglanz, m. zinkenite. -arbeit, /. lead smelting plumbing, -arse-nat, n. lead arsenate, -arsenglanz, m. sarto-rite. -arsenik, m. lead arsenate lead arsenide, -art, /. kind or variety of lead. 

In addition to their concern regarding spray residues of the lead arsenate and organic types, canners whose fruits are sprayed with lime sulfur have reason for concern over the presence of sulfur in their canned products. The presence of elemental sulfur or simple compounds of reduced sulfur in canned foods, especially in those products having an acid character, is objectionable, not only because it may be the source of sulfide flavor and staining, but also because it may actively accelerate the formation of hydrogen by the corrosive action of the product on the container. 

Mercury, tin, lead, arsenic, and antimony form toxic lipophilic organometallic compounds, which have a potential for bioaccumulation/bioconcentration in food chains. Apart from anthropogenic organometallic compounds, methyl derivatives of mercury and arsenic are biosynthesized from inorganic precursors in the natural environment. 

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