摘要:

AbstractChemical forms of water‐soluble and lipid soluble arsenic compounds in marine macroalgae, including edible algae, are reviewed. Major watersoluble arsenic compounds inalgae are arseniccontaining ribofuranosides (ACRs). Red and green algae contain mainly a glycerophospho derivative at the glycerol terminal while brown algae contain a sulfate or sulfonate derivatives at the glycerol terminal together with a glycerophospho derivative. Brown algae which belong to the Sargasso species contain significant amounts of inorganic arsenic in the form of arsenate. Lipid‐soluble arsenic identified in a brown algae (Undaria pinnatifida) was an acylated derivative of an ACR. Thirty‐eight marine algae were analyzed by HPLC/ICP/MS and their arsenic compounds are characterized. The characterization of arsenic compounds may show their role in the chemical taxonomy of algae species in addition to giving an understanding of the toxicological and geochemical implication of the el

ISSN:0268-2605    

DOI:10.1002/aoc.590040303

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractBlackfoot disease is endemic in Chia Yi and Tainan Counties in south‐western Taiwan. Arsenic present in the drinking water taken from wells has been blamed for causing this disease. The discovery in 1975 of fluorescent compounds in these well waters led to the isolation of these substances, to their identification as humic substances containing a large number of elements (among them arsenic), and to the development of an animal model for blackfoot disease. Mice receiving aqueous solutions of these fluorescent substances at a daily dose of 5 mg per 20 g body mass for at least 22 days developed blackfoot and blacktail disease. Work with these fluorescent substances, their chemical properties, and their biological actions is reviewe

ISSN:0268-2605    

DOI:10.1002/aoc.590040304

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractArsenic is ubiquitous in the atmosphere, hydrosphere, pedosphere, lithosphere, and biosphere of the earth. Hot springs in Japan have arsenic concentrations as high as 25 mg kg−1, Generally, the hotter the water the higher are the arsenic concentrations. On average, acidic waters have higher arsenic concentrations than alkaline waters. The arsenic concentrations are positively correlated with the antimony and the lead concentrations. The daily discharge of arsenic from a geothermal well may reach a total of 220 kg. The arsenic concentrations, the temperatures, and the pH values for some Japanese thermal waters are tabulate

ISSN:0268-2605    

DOI:10.1002/aoc.590040305

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractSynthetic inorganic ion exchangers were studied regarding adsorption and desorption features of cacodylic acid [(CH3)2A3O(OH)] with a view to finding a selective adsorbent in aqueos solution. Hydrous oxides of titanium [Ti(IV)], Zirconium [Zr(IV)], manganese [Mn(IV)]and ion [Fe(III)] among synthetic inorganic ion exchangers showed a high selectivity towards cacodylic acid over a wide pH range lower than 12. A large capacity for cacodylic acid (1.0 mmol g−1) was observed for amorphous hydrous titanium dioxide (Am‐HTDO) at pH<5.5 in a solution of ionic strength of 0.1 made with (NaCl + HCl) or (NaCl + NaOH). The uptake by the column method (0.9 mmol g−1) was in good agreement with the batch method. The acid could be quantitatively eluted by 1 mol dm

ISSN:0268-2605    

DOI:10.1002/aoc.590040306

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractEffects of selenium (Se) on the kinetics of incorporation and excretion of74As have been studied by use of a marine diatom,Cylindrotheca fusiformis. For the incorporation experiment, the cells were incubated with carrier‐free74As in a phosphate‐free normal medium, and collected sequentially over 45 h. For the excretion experiment, the cells were transferred to a normal medium and collected sequentially over 95 h. The cell components were fractionated into watersoluble, insoluble and lipid fractions by TLC.74As was mostly incorporated into the water‐soluble fraction and less than 10% of it into the insoluble and lipid fractions. Within a few hours considerable amounts of74As were found in those fractios, but after that the rate of accumulation decreased.74As was excreted into the medium rapidly at the beginning, but the rate of excretion slowed down gradually. In the cells, the amount of As in the insoluble fraction decreased more rapidly than that in the lipid and water‐soluble fractions. The time course changes of74As in the three fractions showed some oscillation of larger amplitude of variation at first and later approached a constant value. Selenium in the medium showed some effects o the rate of arsenic incorporation as well as on the ratio of the three fractions. In the excretion process, selenium changed the amplitude of the variation and the ratio of74As in the three fractions at the late

ISSN:0268-2605    

DOI:10.1002/aoc.590040307

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractIn order to understand the chemical form of arsenic compounds and their distribution in unpoluted areas, concentrations of arsenic compounds in the marine atmosphere were measured in several islands in several oceans. Furthermore, concentration of arsenic compounds were also measured between Tokyo and the Syowa station during a cruise by the Antarctic observation boatShirase. Aerosols in the marine atmosphere were collected by a high‐volume air sampler with a quartz fiber filter. After extracting a sample, an analysis of arsenic compounds in the sample solution was carried out by hydride generation atomic absorption spectrophotometry combined with a cold trap of liquid nitrogen. This technique has a high analytical sensivity, so that it is suitable to determine arsenic compounds at trace level.The atmospheric concentrations of arsenic compounds were at the same level over the Pacific Ocean and the Atlantic Ocean. The concentration range of arsenic compounds over these oceans was 100–200 pg m−3for inorganic arsenic, 10–20 pg m−3for inorganic arsenic. It is considered that these values are the background concentrations in the northern hemisphere. On the other hand, over he Antarctic Ocean in the southern hemisphere, the atmospheric concentrations of inorganic arsenic were very low, and organic arsenics were little found. This fact indicates that arsenic in the atmosphere is strongly influenced by anthropogeni

ISSN:0268-2605    

DOI:10.1002/aoc.590040308

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractChronic toxicity, including tumorigenicity, of gallium arsenide (GaAs), gallium phosphide (GaP) and gallium oxide (Ga2O3) was studied in male ICR mice which received either a subcutaneous or an intraperitoneal injection of each material once only. The doses received either subcutaneously or intraperitoneally were 48 mg Kg−1as Ga or 480 mg Kg−1as Ga of each material suspended in 0.2 cm3of olive oil. The control groups received the vehicle only, either subcutaneously or intraperitoneally.In the study using subcutaneous injections, no tumors were observed in the subcutis at the site of injection, and there was no significant difference concerning the survival periods of each group compared with the control group at the termination of the observation period.In the study using intraperitoneal injections, the total tumor incidence in all the experimental groups, except for the GaAs (480 mg Ga Kg−1) groups, was significantly different compared with the control group. However, all these tumors appeared to be spontaneous, rather than induced by the materials themselves. Moreover, in the GaAs (480 mg Ga Kg−1) and Ga2O3(48 mg Ga Kg−1) groups, the number of survival days was significantly lower compared with the control group.From this study, it seems that neither GaAs, GaP nor Ga2O3were tumorigenic to mice when injected subcutaneously. Although it remains unclear whether the increased production of total tumors in each group following intraperitoneal injections was directly due to the tumorigenic action of GaAs, GaP or Ga2O3or not, it appears that these substances produce a potential systemic toxicity in mice following intraperitoneal i

ISSN:0268-2605    

DOI:10.1002/aoc.590040309

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractTwo media (1/5 ZoBell 2216E and inorganic salt media) were used for degradation experiments. Each arsenical [arsenobetaine, trimethylarsine oxide (TMAO), dimethylarsinic acid (DMA), sodium methanearsonate, sodium arsenate and sodium arsenite] was added to 20cm3of each medium (0.084% as As) in a 30‐cm3Erlenmever flask. The mixtures were kept at 25°C in the dark for 91 days for aerobic cultivation. For anaerobic cultivation, about 5 cm3of liquid paraffin was placed on the surface of each mixture. Under aerobic conditions, arsenobetaine was the only methylarsenical which was rapidly degraded, being converted to several metabolites. In contrast, under aerobic conditions, little or no arsenobetaine (ZoBell or inorganic salt‐media respectively) was converted to its metabolites, while all the methylarsenicals other than arsenobetaine were converted to less methylated compounds. The conversion of inorganic arsenic was observed only in the aerobically incubated ZoBell/arsenite mixture; arsenate was derived from it. A peculiar conversion pattern was observed in the aerobically incubated ZoBell/TMAO mixture; DMA derived from TMAO began to convert to TMAO after 14 days of incubation, and TMAO was the only arsenical in the mixture after 35

ISSN:0268-2605    

DOI:10.1002/aoc.590040310

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractTwo arsenic‐tolerant bacterial species were isolated from a contaminated culture of the algaChlorellasp. One of the bacterial species was identified asPseudomonas putida; both were aerobic heterotrophs. The bacteria grew well in a peptone medium of neutral pH at room temperature and reached the stationary phase in approximately four days. Growth was not impaired by arsenic concentration as high as 1000 mg dm−3As in the form of arsenate, but decreased drastically at higher concentrations.P. putidagrown in a peptone medium with 10 mg dm−3As as arsenate, reached a maximal arsenic concentration of 67 mg kg−1(dry mass) after 48 h of growth in the late log phase. Most of the arsenic in the cells was inorganic and 3% of the arsenic was in the trimethylated form. During the stationary phase the bacteria excreted arsenic largely in the inorganic, but also in the inorganic, but also in the mono‐, di‐, and trimethyl

ISSN:0268-2605    

DOI:10.1002/aoc.590040311

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe transport and transformation of arsenic were investigated in the food chainChlorellaandPhormidiumsp. (autotrophic freshwater algae)–Moinasp. (zooplanktonic grazer)–Poeciliasp. (carnivorous guppy). The algae were grown for seven days in a modified Detmer medium containing 100 mg dm−3arsenic as Na2HAsO4. The algae (Chlorella0.64 mg g−1dry mass;Phormidium2.9 mg g−1dry mass) were fed toMoinafor seven days.Moinaacquired arsenic concentrations of 76 μg g−1(fromChlorella) and 111 μg g−1(fromPhormidium). The guppy feeding onMoina(with arsenic fromChlorella) had the lowest arsenic concentrations (5.6 μg g−1) among these organisms.Whereas the arsenic in the algae was almost all in inorganic form, 85% of the arsenic in the guppy was in di‐ and tri‐methylated form. The higher Percentages of methylated arsenic at the higher trophic levels could be the result of preferential uptake or retention of methylarsenic compounds or of methylation of arsenic compounds b

ISSN:0268-2605    

DOI:10.1002/aoc.590040312

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY