Lead arsenites

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). 

Lead Arsenites.—An investigation of the ternary system PbO-As203-H20 at 25° C. gives evidence of the formation of the metarsenite, Pb(AsO,)2, only.8 Several other well-defined arsenites are known, however. 

Lead arsenite is readily obtained by an electrolytic process.6 The eatholyte may be a 15 per cent, solution of sodium hydroxide or of a sodium salt, or a 30 per cent, solution of potassium hydroxide, the cathode being of nickel. The anolyte is a solution of an alkali arsenite neutralised towards phenolphthalein by means of acetic acid, and the anode is of lead. The cathode space is separated by a diaphragm of vegetable parchment. Ormont obtained a current yield of 97 per cent., and the average energy yield amounted to 1 kg. per kilowatt-hour. 

A colloidal solution of lead arsenite has been obtained by the following method. A solution of lead acetate is treated with a 10 per cent, solution of sodium lvsalbinate, and after washing the precipitate with hot water, it is dissolved in a dilute aqueous solution of sodium hydroxide containing sodium dihvdrogen arsenite. The liquid, after keeping for some hours, is filtered and dialysed until the outside liquor is free from arsenic. The solution in the dialyser is concentrated, mixed with alcohol and ether, and dried over sulphuric acid in a vacuum. A pale yellow horny mass remains, which dissolves readily in water to form a sol.3... 

Blakeley BR, Sisoda CS, Mukkar TK. 1980. The effect of methyhnercury, tetraethyl lead, and sodium arsenite on the humoral immune response in mice. Toxicol Appl Pharm 52 245-254. 

Kharab P, Singh I. 1985. Genotoxic effects of potassium dichromate, sodium arsenite, cobalt chloride and lead nitrate in diploid yeast. MutRes 155 117-120. 

By the action of chloroacetic acid on sodium arsenite isolated and purified through the lead salt. Romberg and Ohman, Svensk. Kem. Tids. 36, 119 (1924). [C. A. 19, 36 (1925).]... 

Fig. 31.5. Minerals formed during reaction at 25 °C of a hypothetical acid drainage water with calcite (top), and fractions of the amounts of arsenite, arsenate, copper, lead, and zinc present initially in solution that sorb onto ferric hydroxide over the course of the reaction path (bottom). Bottom figure is plotted against pH, which increases as the water reacts with calcite.

Arsenic uptake in rabbit intestine is inhibited by phosphate, casein, and various metal-chelating agents (USEPA 1980). Mice and rabbits are significantly protected against sodium arsenite intoxication by (V-(2,3-dimercaptopropyl)phthalamidic acid (Stine et al. 1984). Conversely, the toxic effects of arsenite are potentiated by excess dithiols, cadmium, and lead, as evidenced by reduced food efficiency and disrupted blood chemistry in rodents (Pershagen and Vahter 1979). 

Lead arsenate Copper acetoarsenite CALIFORNIA QUAIL, Callipepla californica Sodium arsenite COMMON BOBWHITE, Colinus virginianus Copper acetoarsenite Sodium cacodylate... 

Inorganic arsenicals such as arsenic trioxide, sodium arsenite, lead arsenate, calcium arsenate and Paris Green have been used for many years as soil sterilants. Organic arsenical herbicides, in which the organic group is bonded directly to the arsenic atom, have been used extensively for post-emergence control of weeds in cotton. Several of the more important herbicides are sodium cacodylate (monosodium dimethylarsenic acid) and sodium salts of methane arsonic acid. The latter compounds exist in two principal forms the monosodium salt (MSMA) at pH6.4 and the disodium salt (DSMA) at pH10.2. 

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