Arsenic Table methylation

Rainbow trout (Oncorhynchus mykiss) fed diets containing up to 90 mg As+5/kg were slightly affected, but those given diets containing >120 mg As/kg (as As+3 or As+5) grew poorly, avoided food, and failed to metabolize food efficiently. No toxic effects were reported over 8 weeks of exposure to diets containing 1600 mg/kg, as methylated arsenicals (Table 28.4). Dietary disodium... 

It has been su ested, based upon animal data, that a possible arsenic requirement for humans eating 8.37MJ (2000 kcal) would be 12-25 pgday this is near the typical daily intake shown in Table 3. Because of mechanisms for the homeostatic regulation of arsenic (including methylation,... 

Organomineral peroxides of antimony arsenic, boron, magnesium, tin, cadmium, lead, silicon, and 2inc have been prepared by autoxidation and some are Hsted in Table 3 (33,44,60,93,115). For example, dimethyl cadmium reacts with oxygen to form methylperoxy methyl cadmium [69331-62-0] and bis(methylperoxy) cadmium. 

The chloride is used to manufacture silicones, tetramethyl lead and triptane (2,2,3 trimethylbutane). Lesser uses include the manufacture of butyl rubber, higher halogenated methanes, methyl cellulose, quaternary ammonium compounds, methyl mercaptan, methionine, fungicides and pesticides (primarily the Me-arsenate herbicides). Recently the chlorinated fluorocarbons have replaced CH3CI as high volume refrigerants and propellants (ref. 32) Tables 12 and 13 list the chemical and physical properties and potential numbers of workers exposed to the monohalomethanes. 

The reaction product of arsenic trichloride (see Table 1) with 3,4-dimercaptotoluene, 2-chloro-5-methyl-l,3,2-benzodithiarsole, still contains an active chlorine atom, rendering its determination by GC/MS difficult. The derivatization reaction can also be carried out with 2-chlorovinylarsenic oxide (lewisite oxide, CAS 3088-37-7), which is one of the degradation products of lewisite 1. Thus, the highly reactive arsenous compounds can be detected as less reactive derivatives amenable to GC/MS. 

Organic As compounds do not exactly fit into this order of toxicity. Compounds such as methyl- ethyl- phenyl- or 2-chlorvinyl-dichlorarsine (Lewisite) are very toxic and have been used also as chemical weapons (Compton 1987). Examples of environmentally, toxicologically and biologically important arsenic compounds to be discussed in this chapter in more detail are shown in Table 6.1 and Figure 6.1. 

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