Radioactivity water solubility

Radon-222 [14859-67-7] Rn, is a naturally occuriing, iaert, radioactive gas formed from the decay of radium-226 [13982-63-3] Ra. Because Ra is a ubiquitous, water-soluble component of the earth s cmst, its daughter product, Rn, is found everywhere. A major health concern is radon s radioactive decay products. Radon has a half-life of 4 days, decayiag to polonium-218 [15422-74-9] Po, with the emission of an a particle. It is Po, an a-emitter having a half-life of 3 min, and polonium-214 [15735-67-8] Po, an a-emitter having a half-life of 1.6 x lO " s, that are of most concern. Polonium-218 decays to lead-214 [15067-28A] a p-emitter haviag = 27 min, which decays to bismuth-214 [14733-03-0], a p-emitter haviag... 

The extensive industrial and commercial utilization of water-soluble polymers (polyelectrolytes) in water treatment has been developed based on the charge along the polymer chains and the resultant water solubility. The use of water-soluble polymers in water treatment has been investigated by several authors [5-26] in the recovery of metals radioactive isotopes, heavy metals, and harmful inorganic residues. This allows recycling water in the industrial processes and so greatly saves... 

In previous works [18-20,23,102] water-soluble polymers such as polyacrylamide (pAM), polysodium acrylate (pAA Na), poly(acrylamide-sodium acrylate) (pAM-AA Na), poly(acrylamide-diallyethylamine-hy-drochloride) (pAM-DAEA-HCl), and poly(acrylamide-sodium acrylate-diallyethylamine-hydrochloride) (pAM-AANa-DAEA-HCl) were used in the recovery of cations and some radioactive isotopes from aqueous solutions. It was found that the floe is formed between the added polymer and ions of the solution in the flocculation process with the formation of a crosslinked structure. The formed cross-linked structure is characterized by [103-105] ... 

Denmark 1.5 days after the explosion. Air samples collected at Roskilde, Denmark on April 27-28, contained a mean air concentration of 241Am of 5.2 pBq/m3 (0.14 fCi/m3). In May 1986, the mean concentration was 11 pBq/m3 (0.30 fCi/m3) (Aarkrog 1988). Whereas debris from nuclear weapons testing is injected into the stratosphere, debris from Chernobyl was injected into the troposphere. As the mean residence time in the troposphere is 20-40 days, it would appear that the fallout would have decreased to very low levels by the end of 1986. However, from the levels of other radioactive elements, this was not the case. Sequential extraction studies were performed on aerosols collected in Lithuania after dust storms in September 1992 carried radioactive aerosols to the region from contaminated areas of the Ukraine and Belarus. The fraction distribution of241 Am in the aerosol samples was approximately (fraction, percent) organically-bound, 18% oxide-bound, 10% acid-soluble, 36% and residual, 32% (Lujaniene et al. 1999). Very little americium was found in the more readily extractable exchangeable and water soluble and specifically adsorbed fractions. 

Experiments with monkeys given intramuscular injections of a mineral oil emulsion with [l-14C] -hexa-decane tracer provide data illustrating that absorbed C-16 hydrocarbon (a major component of liquid petrolatum) is slowly metabolized to various classes of lipids (Bollinger 1970). Two days after injection, substantial portions of the radioactivity recovered in liver (30%), fat (42%), kidney (74%), spleen (81%), and ovary (90%) were unmetabolized -hexadecane. The remainder of the radioactivity was found as phospholipids, free fatty acids, triglycerides, and sterol esters. Essentially no radioactivity was found in the water-soluble or residue fractions. One or three months after injection, radioactivity still was detected only in the fat-soluble fractions of the various organs, but 80-98% of the detected radioactivity was found in non-hydrocarbon lipids. 

Very long nanotubes may not be able to be removed from the body by immune system cells like macrophages and hence may linger in the body for a long time. There is some data that radioactive-labeled water-soluble fullerenes are cleared... 

When fish of both populations were exposed to 80 yg/1 14c-aldrin, dieldrin was the only detectable metabolite in the organic extracts of the liver. The percentage of radioactivity in the water-soluble fraction in both populations was small. Although previous work had indicated a greater production of water-soluble metabolite(s) in the R population (15), more recent work indicated that the relative proportion of racTToactivity in the water-soluble fraction was similar in both populations (Table VII). 

Table VII - Radioactivity in Water-soluble Fractions of Livers of Susceptible (S) and Resistant (R) Fish Exposed to 80 yg/l 14C-aldrin for 6 hra... 

Population ng aldrin equivalents/ mg protein Water soluble radioactivity x 100/ total hepatic radioactivity... 

No metabolites of dieldrin were observed in organic extracts of livers of either S or R fish exposed to 30 yg/l 4c-dieldrin for 6 hr (5j (Table IX). A small percentage of the radioactivity was found in the water-soluble fraction. Therefore, it appears that little metabolism of dieldrin occurs in mosquitofish livers in either population. In addition, the degree of intoxication in S fish did not appear to affect the metabolism either qualitatively or quantitatively. 

Extraction of the fish showed that 81% of the carbon-14 residues were organosoluble, 13% were polar water-soluble products and 6% unextractable. Chromatography of the organo-soluble radioactivity showed that a large proportion (87%) was still very polar in nature with DDT accounting for 8%, DDE 3% and DDD 2%. 

In addition to the two model substances, Table V includes similar data on two water soluble pollutants. For phenol, the hepatic compartment at 4 hrs. contained both a large concentration and a high percentage of the administered dose. As is indicated by the urine and kidney levels, the importance of the renal route is evident. While there are no other unique distributional factors noted for phenol from these data, the fact that after 24 hrs. only about 30% of the administered radioactive compound is accounted for, as well as other known properties of phenol, suggests that it may be excreted via the gills (28) or through the skin. 

Deep geological disposal is the most favored solution for the permanent disposal of nuclear wastes with long half-lives. Although the locations of the burial places are selected with outmost care to avoid migration of the wastes in nature over a very long period of time, no barrier can be safe forever, so, numerous studies are in progress to determine the main factors that could cause leaks of radioactive nuclides. Soluble compounds in ground water are likely to play a major role in the release of actinides. 

Of the total recovered radioactivities after AgNO, treatment (water soluble plus AgCl) of the aqueous buffer phase takem from C1-toxaphene cultures (Table 5), 30.3% was found as water soluble metabolites and 69.7% as free chloride ion under aerobic conditions. Under anaerobic conditions, 17.0% was found as water soluble metabolites and 83.0% as free chloride ion. 

As shown in Table III, there is no significant difference in glucose uptake by cotton leaf discs immediately after exposure, but after 24 hr the uptake has nearly doubled. The percentage distribution of radioactivity in various extraction fractions is approximately the same in control and ozone-treated tissues. CO2 evolution from the added glucose is virtually identical in control and treated tissues. Isotope incorporation into the water soluble fraction, which would include amino acids, organic acids, and soluble carbohydrate, is also quite similar. Some distributional differences in the insoluble fraction are noted between... 

Polymer encapsulation technology (PET) was designed to stabilize radioactive materials and wastes. Polymer encapsulation uses nonvolatile polymers with excellent heat resistance, low water solubility, chemical stability, and excellent radiation resistance. Once materials have been mixed with the encapsulant, the mixture expands and hardens. This process prevents radioactivity from escaping and confines radioactive particles to the polymer structure. 

Five metabolites were detected in the feces of rats and mice collected over a 5-day period after administration of a single dose of " C-2,2, 4,4 -tctraBDE (Om and Klasson-Wehler 1998). Although the precise structure was not identified, the data suggested that the metabolites were hydroxylated derivatives of tetraBDE. An additional metabolite, possibly a methyl thio-substituted tetraBDE, was also detected in the feces. Yet, at least 85% of the radioactivity in the feces corresponded to the parent compound. A water-soluble metabolite was detected in urine from mice, but could not be isolated. Unchanged tetraBDE was also the major compound in all tissues analyzed, but minor amounts of hydroxylated tetraBDE metabolites were detected. 

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