Ammonium salts toxicity

Diethyl dicarbonate (diethyl pyrocarbonate) was used in the past as a preservative for soft drinks and some alcohohc beverages (including wine). In aqueous solution, however, diethyl dicarbonate is rapidly hydrolysed to ethanol and carbon dioxide, and in alcoholic beverages it is transformed into diethyl carbonate by reaction with ethanol. In the presence of ammonium salts toxic ethyl carbamate then results, which is also known as urethane (Figure 11.2). For these reasons, diethyl dicarbonate is not approved in the EU, but the approved compound is dimethyl dicarbonate (E242), which can be used for the preservation of soft drinks, teas, herbal teas and in some countries to stabilise wine. The methyl carbamate produced from dimethtyl dicarbonate is a non-toxic substance. In treated wines it occurs in amounts up to 10 xg/l. 

Care must be exercised in using sodium nitrite near other chemicals. It is incompatible with ammonium salts, thiocyanates, thiosulfates, and strong reducing agents. In acid solutions, sodium nitrite evolves toxic NO in the presence of secondary amines it can form nitrosamines which are suspected carcinogens. 

The ammonium salts of vanadic acid and vanadium pentoxide have been Hsted as toxic constituents in soHd wastes under the Resource Conservation and Recovery Act (27). 

Toxic intermediate products are produced during hydrolysis. Approximate half-life in water at 25°C is 1.3 min. Decomposition comes through slow change into quaternary ammonium salts. Decomposition point is below 94°C. 

A broad range of information pertaining to the toxicity of several classes of surfactants including anionic (linear alkylbenzene sulfonates (LAS), alkylether sulfates (AES), alkyl sulfates (AS), non-ionic (alkylphenol ethoxylates (APEO)), cationic (ditallow dimethyl ammonium chloride (DTDMAC)—a group of quaternary ammonium salts of distearyl ammonium chloride (DSDMAC)) and amphoteric surfactants (alkyl-betaines) is available. Several reviews of the scientific literature have been published [3-5,20]. 

It is well known that the amino and acetamido group and quaternary ammonium groups often render compounds physiologically active. Particular reference may be made to the work of Haworth and his collaborators on the toxic action associated with quaternary ammonium salts.1... 

It was a result of demand from industry in the mid-1960s for an alternative to be found for the expensive traditional synthetic procedures that led to the evolution of phase-transfer catalysis in which hydrophilic anions could be transferred into an organic medium. Several phase-transfer catalysts are available quaternary ammonium, phosphonium and arsonium salts, crown ethers, cryptands and polyethylene glycols. Of these, the quaternary ammonium salts are the most versatile and, compared with the crown ethers, which have many applications, they have the advantage of being relatively cheap, stable and non-toxic [1, 2]. Additionally, comparisons of the efficiencies of the various catalysts have shown that the ammonium salts are superior to the crown ethers and polyethylene glycols and comparable with the cryptands [e.g. 3, 4], which have fewer proven applications and require higher... 

Other biocidal agents that can be used in closed industrial water systems include copper(II) salts (which, however, can cause corrosion of metals), chlorinated phenols such as sodium pentachlorophenate (NaOCfiCls, which is toxic), and quaternary ammonium salts (lUN+X-). 

Since Os04 is volatile, toxic and expensive, considerable effort has been devoted to the catalytic application of the cis dihydroxylation of alkenes in the presence of excess cooxidant.57-290 Previous procedures used metal chlorate (Hoffman reagent),339 or hydrogen peroxide (Milas reagent)350 as cooxidant, usually in Bu OH or acetone.290 Recent procedures utilize t-butyl hydroperoxide in conjunction with ammonium salts (Et4NOH or Et4NOAc)57,351 or N-methylmorpholine N-oxide,352 and are generally more selective. 

The toxic Japanese gastropod Turbo marmorata contains the two toxins, turbotoxins A (1983) and B (1984), isolated as bis-trifluoroacetates (1824, 1825). The turbotoxins A and B show LD99 = 1.0 and 4.0 mg kg 1 in mice. The simple iodinated ammonium salt 1985 is also found in this animal (1826). The red alga Halopytis incurvus contains the simple brominated phenols 1986 and 1987, which were isolated as the methyl esters and methyl ethers (1827). These presumed degradation products of tyrosine are related to earlier reported brominated metabolites (1). 

The synthesis of DOTMA was performed first using D-mannitol-3,4-acetonide as a starting material (Figure 15.2). This tedious procedure was improved for the synthesis of a variety of DOTMA related cationic lipids (Bennett et al., 1995). Their synthesis was accomplished using a simplified synthetic approach also suitable for the synthesis of DOTMA (Figure 15.3). This procedure allowed access to quaternary ammonium esters with less toxicity and to a variety of quaternary ammonium salts (Figure 15. 4) with improved transfection efficacy. 

A specific type of electrostatic anion receptor constitutes the compounds capable of chromate (CrO -) or dichromate (Cr2Oj ) recognition. These anions are particularly important because of their toxicity and the presence of these pollutants in the environment (waste water and soils). The corresponding receptors are based on the protonated amines [68,69] (such as 54), protonated forms of similar compounds [70,71] or on the quaternary ammonium salts [72] of type 55. Thus, ammonium salt 54 (in the form of chloride) can transfer chro-... 

The first human experiments which suggested a toxic effect of ammonia in disease were done by Van Caulaert. The revival and extension of this work by the group led by Davidson (G2) in the Boston City Hospital has stimulated widespread interest in ammonia as a factor in the production of mental symptoms in liver disease. The ability of various factors, such as urea feedings, high-protein diet, cation resins in the ammonia cycle, and amino acids, to induce symptoms of coma in patients with liver disease (G2, M3, M4, P7, S8) made it quite clear that ammonia was associated with the symptom complex called hepatic coma. The severe toxicity of ammonia in animals and the ability of intravenous or oral ammonium salts to provoke episodes of impending liver coma tended to substantiate the clinical impressions. Rapid confirmation of these observations was furnished by the experiments of other groups (Bll, C2, E2, FI). 

A vigorously stirred suspension of 0.2 to 1 mole of sodium amide in 200 ml of xylene, in which were dissolved 0.1 mole of a,a-diphenyl-7-hexamethyleneimino butyronitrile was boiled for 12 hours. Thereupon the excess of sodium amide was decomposed with water and the xylene layer was separated, washed with water and extracted with hydrochloric acid. This acidic extract was made strongly alkaline with concentrated lye and the separated base was extracted with ether. After drying, the ether was evaporated and the l,l-diphenyl-3-hexamethyleneimino propane distilled in vacuo. The boiling point was 170-174°C/1 mm, the refractive index nD20 = 1.56 36, and the density d420 = 1.009. From the oil obtained several acid additions and quaternary ammonium salts can be obtained by reaction with acids containing a non-toxic anion or esters thereof. The hydrochloric acid salt, for instance, melts at 189-192°C, the methiodide at 174-177°C under decomposition. 

SAFETY PROFILE Experimental reproductive effects. Human mutation data reported. Reaction with ammonia or ammonium salts yields fulminating gold, a heat-, friction-, and impact-sensitive explosive similar to mercury and silver fulminates. See also GOLD COMPOUNDS and CHLORIDES. When heated to decomposition it emits toxic fumes of CT. 

A powerful oxidizer. Incompatible with combustible materials, ammonium salts, nitrogenous materials. Used to chlorinate swimming pools and in cleaning, bleaching, disinfecting, sanitizing. When heated to decomposition it emits very toxic fumes of Cr, NOx, and Na20. 

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