Poisons, soluble

Barium salt dihydrate, C,4H10BaC>4.2H2O, barium benzoate. Nacreous leaflets. Poisonous Soluble in about 20 parts water slightly sol in ale. 

Mercury salt, C,ll. AsdIg04, mercuric cacedylatc. Hygroscopic, somewhat unstable cryst powder. Poisonous/ Soluble in water, alcohol practically in sol in ether. Keep well closed. 

Tetrahydrate. white, odorless, cryst powder. Poisonous Soluble in about 6 parts water, about 100 parts alcohol. The aq soln is moderately acid to litmus. 

Action on the Economy.—The oxids and hydroxid act as corrosives, by virtue of their alkalinity, and also as tru 5 poisons. All soluble compounds of Ba, and those which are readily concerted into soluble compounds in the stomach, are actively poisonous. Soluble sulfids, followed by emetics, are indicated as Antidotes. The sulfate, notwithstanding its insolubility in water, is poisonous to some animals. 

Toxic elements Elements that have no biological role and are poisonous in the elemental form or produce poisonous soluble compounds exhibiting toxic effects mechanisms of these effects often He in the inhibition of metaboUcaUy significant enzymes as a consequence of interaction of the toxic element with the enzyme molecule the most important toxic elements in food are particular metals (Pb, Cd and Hg) and metalloids (As). 

Properties Glossy, colorless crystals or white powder, turning.yellow on exposure to light odorless tasteless at first, then bitter poisonous Soluble in chloroform, alcohol, alkalies and most volatile and fatty oils very slightly soluble in water. Solutions are levorotatory. Sp.gx. 1.187 m.p. 170-173 C b.p. sublimes specific rotation —170 to —175 (2 g/lOO ml alcohol). 

H2N (CH2]5 NH2. a syrupy fuming liquid, b.p. 178-180 - C. Soluble in water and alcohol. Cadaverine is one of the ptomaines and is found, associated with pulrescine, in putrefying tissues, being formed by bacterial action from the amino-acid lysine. It is found in the urine in some cases of the congenital disease cystinuria. The free base is poisonous, but its salts are not. 

Phosphine is a colourless gas at room temperature, boiling point 183K. with an unpleasant odour it is extremely poisonous. Like ammonia, phosphine has an essentially tetrahedral structure with one position occupied by a lone pair of electrons. Phosphorus, however, is a larger atom than nitrogen and the lone pair of electrons on the phosphorus are much less concentrated in space. Thus phosphine has a very much smaller dipole moment than ammonia. Hence phosphine is not associated (like ammonia) in the liquid state (see data in Table 9.2) and it is only sparingly soluble in water. 

Both chloramine-T and dichloramine-T have marked antiseptic properties, chloramine-T being most frequently used because of its solubility in water. Aqueous solutions of chloramine-T can be used either for external application, or for internal application to the mouth, throat, etc, as chloramine-T in moderate quantities is non-toxic its aqueous solution can also be effectively used when the skin has come in contact with many of the vesicant liquid poison-gases, as the latter are frequently organic sulphur or arsenic derivatives which combine with or are oxidised by chloramine-T and are thus rendered harmless. 

Rya.nia., The root and stem of the plant yania speciosa family Flacourtiaceae, native to South America, contain from 0.16—0.2% of iasecticidal components, the most important of which is the alkaloid ryanodine [15662-33-9] C25H250 N (8) (mp 219—220°C). This compound is effective as both a contact and a stomach poison. Ryanodine is soluble ia water, methyl alcohol, and most organic solvents but not ia petroleum oils. It is more stable to the action of air and light than pyrethmm or rotenone and has considerable residual action. Ryania has an oral LD q to the rat of 750 mg/kg. The material has shown considerable promise ia the control of the European com borer and codling moth and is used as a wettable powder of ground stems or as a methanohc extract. Ryanodine uncouples the ATP—ADP actomyosia cycle of striated muscle. 

Alkali AletalIodides. Potassium iodide [7681-11-0] KI, mol wt 166.02, mp 686°C, 76.45% I, forms colorless cubic crystals, which are soluble in water, ethanol, methanol, and acetone. KI is used in animal feeds, catalysts, photographic chemicals, for sanitation, and for radiation treatment of radiation poisoning resulting from nuclear accidents. Potassium iodide is prepared by reaction of potassium hydroxide and iodine, from HI and KHCO, or by electrolytic processes (107,108). The product is purified by crystallization from water (see also Feeds and feed additives Photography). 

Fuel Dissolution. In the American and British plants, LWR fuel pieces typically fall directly from the shear into a dissolver basket, which fits inside the dissolver vessel. A soluble poison such as gadolinium is added to the nitric acid to prevent criticahty. The massive end fittings are sometimes separated from the fuel pieces before the latter enter the dissolver. The French have installed continuous rotary dissolvers in the UP3 and UP2-800 plants at La Hague. The units each consist of a dmm rotating within a geometrically favorable slab tank (13). 

The second control mechanism is the soluble reactor poison boric acid [10043-35-3] Natural boron contains 20% boron-10 [14798-12-0] ... 

The third control is by use of a fixed burnable poison. This consists of rods containing a mixture of aluminum oxide and boron carbide, included in the initial fuel loading using the vacant spaces in some of the fuel assembhes that do not have control clusters. The burnable poison is consumed during operation, causing a reactivity increase that helps counteract the drop owing to fuel consumption. It also reduces the need for excessive initial soluble boron. Other reactors use gadolinium as burnable poison, sometimes mixed with the fuel. 

Metals and metalloids that form alkyl compounds, eg, methylmercury and methylarsenic acid, tributjltin, deserve special concern because these compounds are volatile and accumulate in cells they are poisonous to the central nervous system of higher organisms. Because methylmercury or other metal alkyls may be produced at a rate faster than it is degraded by other organisms, it may accumulate in higher organisms such as fish. Hg species are also reduced to elementary Hg which is soluble in water but lost by volatilization to the atmosphere (40). 

Treatment. Treatment of poisoning from soluble barium salts may be preventive or curative (47,51). Preventive treatment involves inhibition of intestinal absorption by administering such soluble sulfates as magnesium or sodium, causing precipitation of barium sulfate in the alimentary tract. 

---