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Featured researches published by Reiji Kubota.


Environmental Toxicology and Chemistry | 2005

Body distribution of trace elements in black‐tailed gulls from Rishiri Island, Japan: Age‐dependent accumulation and transfer to feathers and eggs

Tetsuro Agusa; Taro Matsumoto; Tokutaka Ikemoto; Yasumi Anan; Reiji Kubota; Genta Yasunaga; Takashi Kunito; Shinsuke Tanabe; Haruo Ogi; Yasuyuki Shibata

Body distribution and maternal transfer of 18 trace elements (V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Hg, Tl, and Pb) to eggs were examined in black-tailed gulls (Larus crassirostris), which were culled in Rishiri Island, Hokkaido Prefecture, Japan. Manganese, Cu, Rb, Mo, and Cd showed the highest levels in liver and kidney, Ag, Sb, and Hg in feather, and V, Sr, and Pb in bone. Maternal transfer rates of trace elements ranged from 0.8% (Cd) to as much as 65% (Tl) of maternal body burden. Large amounts of Sr, Ba, and Tl were transferred to the eggs, though maternal transfer rates of V, Cd, Hg, and Pb were substantially low. It also was observed that Rb, Sr, Cd, Cs, and Ba hardly were excreted into feathers. Concentrations of Co in liver, Ba in liver and kidney, and Mo in liver increased significantly with age, whereas Se in bone and kidney, Hg in kidney, and Cr in feather decreased with age in the known-aged black-tailed gulls (2-20 years old). It also was suggested that feathers might be useful to estimate contamination status of trace elements in birds, especially for Hg on a population basis, although the utility is limited on an individual basis for the black-tailed gulls. To our knowledge, this is the first report on the maternal transfer rate of multielements and also on the usefulness of feathers to estimate contamination status of Hg in birds on a population basis.


Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 2008

Multivariate characterization of elements accumulated in King Bolete Boletus edulis mushroom at lowland and high mountain regions.

Jaromir J. Falandysz; Takashi Kunito; Reiji Kubota; Leszek Bielawski; Aneta Frankowska; J. Falandysz; Shinsuke Tanabe

Based on ICP-MS, ICP-OES, HG-AAS, CV-AAS and elementary instrumental analysis of King Bolete collected from four sites of different soil bedrock geochemistry considered could be as mushroom abundant in certain elements. Kings Bolete fruiting bodies are very rich in K (> 20 mg/g dry weight), rich in Ca, Mg, Na, Rb and Zn (> 100 μg/g dw), and relatively also rich in Ag, Cd, Cs, Cu, Fe, Mn and Se (> 10 μg/g dw). The caps of King Bolete when compared to stipes around two-to three-fold more abundant are in Ag, Cd, Cs, Cu, Hg, K, Mg, Mo, N, Rb, Se and Zn. King Bolete collected at the lowland and mountain sites showed Ag, Ba, Co, Cr, Hg, K, Mg, Mn, Mo and Na in caps in comparable concentrations, and specimens from the mountain areas accumulated more Cd and Sb. Elements such as Al, Pb and Rb occurred at relatively elevated concentration in King Bolete picked up at the metal ores-rich region of the Sudety Mountains. Because of high bioconcentration potential King Bolete at the background sites accumulate in fruiting bodies great concentrations of problematic elements such as Cd, Pb and Hg, i.e. up to nearly 20, 3 and 5 μg/g dw, on the average, respectively. The interdependence among determined mineral elements examined were using the principal components analysis (PCA) method. The PCA explained 56% of the total variance. The metals tend to cluster together (Ba, Cd, Cs, Cr, Ga, Rb, Se, Sr and V; K and Mg; Cu and Mo). The results provided useful environmental and nutritional background level information on 26 minerals as the composition of King Bolete from the sites of different bedrock soil geochemistry.


Journal of Environmental Science and Health Part B-pesticides Food Contaminants and Agricultural Wastes | 2008

Some mineral constituents of Parasol Mushroom (Macrolepiota procera)

Jerzy Falandysz; Takashi Kunito; Reiji Kubota; Magdalena Gucia; Aneta Mazur; Jaromir J. Falandysz; Shinsuke Tanabe

This article reports background concentrations of Ag, Ba, Cd, Co, Cr, Cs, Cu, Ga, Hg, Mn, Mo, Pb, Rb, Sb, Sr, Se, Tl, V and Zn in caps and stalks of M. procera collected from four spatially distant sites across Poland. The elements were determined using inductively coupled plasma-mass spectrometry (ICP-MS), hydride generation atomic absorption spectrometry (HG-AAS) or a cold vapor atomic absorption spectrometry (CV-AAS). Copper, zinc, rubidium, selenium, chromium and cobalt were the most abundant amongst elements determined in this mushroom. Some elements (Cu, Zn, Rb, Se, Pb, Hg, Cd, Mo) occurred at greater concentrations in the caps than stalks of M. procera and some (Ag, Ba, Sr, V, Tl) dominated in the stalks, while for some other this proportion was similar or varied (Mn, Cr, Co, Ga, Sb, Cs) depending on the sampling site. For elements such as copper, zinc, rubidium as well as selenium some spatial similarity in distribution and/or concentration values both in caps and stalks was noted. Cadmium and lead content in caps of M. procera was usually below the European Union tolerance limit value of 2.0 and 3.0 μg/g dw set for cultivated mushrooms, respectively. These two toxic metals have been found in elevated concentration in M. procera from unpolluted stands outside of Poland as reported by some authors, which implies the possibility of relatively high background levels in this species.


Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 2007

Selected elements in fly agaric Amanita muscaria

Jaromir J. Falandysz; Takashi Kunito; Reiji Kubota; Krzysztof Lipka; Aneta Mazur; J. Falandysz; Shinsuke Tanabe

Concentrations of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Cs, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Pb, Rb, Se, Sb, Sr, V, Tl and Zn have been determined in the whole fruiting bodies, as well as separately in caps and stalks, of fly agaric collected from three geographically distant sites in northern part of Poland. The elements were determined using ICP-MS, ICP-OES, HG-AAS and CV-AAS, respectively. For elements such as Al, Ba, Cr, Fe, Ga, Mo, Mn, Pb, Sb, Sr, Tl, and V concentrations were similar in the caps and stalks, respectively, and for K, Zn, Ag, Ca, Cd, Cu, Hg, Mg, Rb and Se were greater in the caps, while for Co, Cs and Na in the stalks. For Ag, Al, Ba, Ca, Cd, Co, Cr, Cs, Fe, Ga, Hg, Mn, Mo, Pb, Rb, Sb, Sr, Tl and V concentration in the caps showed spatial variations (P < 0.05), while for Cu, K, Mg, Na, Se and Zn was independent of the site. The elements such as K with median or mean in the caps between 37,000 and 43,000 μg/g·dm and Mg with 920 and 1,100 μg/g dm were most abundant. Next, within median values range from approximately 100 to 500 μg/g dm were such as Ca, Fe and Al, and in descending order they followed by Rb (100–400 μg/g dm); V, Na, Zn (50–200 μg/g dm); Cu, Mn (10–50 μg/g dm); Cd (10–20 μg/g dm); Se (5 μg/g dm); Ba (< 1–3); Cr, Ag, Pb, Sr (< 1–2 μg/g dm); Cs, Co, Hg (< 1–1 μg/g dm); Ga (< 0.5), Sb, Mo and Tl (< 0.1 μg/g dm).


Environmental Pollution | 2001

Arsenic accumulation in the liver tissue of marine mammals.

Reiji Kubota; Takashi Kunito; Shinsuke Tanabe

Arsenic concentrations were determined in livers of 226 individuals representing 16 different marine mammal species to elucidate its accumulation with age, sex, and feeding habits. Arsenic concentrations varied widely among species and individuals, and ranged from < 0.10 to 7.68 micrograms g-1 dry weight. Marine mammals feeding on cephalopods and crustaceans contained higher arsenic concentrations than those feeding on fishes. No significant gender difference in arsenic concentration was found for almost all the species. Also, no apparent trend with age (or body length) in arsenic accumulation was found for most of the species. It was noted that two seal species, Baikal seal and Caspian seal, from landlocked water environments, contained lower arsenic concentrations than the marine species. To our knowledge, this is the first comprehensive study of arsenic accumulation in a wide range of marine mammal species.


Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 2007

Selected elements in Brown Birch Scaber Stalk Leccinum scabrum.

Jerzy Falandysz; Takashi Kunito; Reiji Kubota; Leszek Bielawski; Aneta Mazur; Jaromir J. Falandysz; Shinsuke Tanabe

A survey of 26 metallic elements and metalloids such as Ag, Al, Ba, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Sb, Se, Sr, Tl, V and Zn was carried out using ICP-MS, ICP-OES, HG-AAS and CV-AAS in the caps and stalks of edible mushroom Brown Birch Scaber Stalk collected from two lowland and one mountain sites in Poland. Ag, Al, Cd, Cr, Cs, Cu, Fe, Hg, K, Mg, Mo, Pb, Rb, Se, V and Zn occurred in greater concentration in the caps than stalks of Brown Birch Scaber Stalk, and opposite situation was for Tl and Na. Brown Birch Scaber Stalk collected from the site in Sudety Mountains did contain Al, Ba, Cs, Fe, Ga, Ni, Pb, Sr and V in significantly greater concentration when compared to specimens collected from the lowland sites, and what imply on significance of geological origin and/or soil substrate pollution impacting on mineral composition of this mushroom species. The results provide useful environmental and nutritional baseline level information on mineral composition of Brown Birch Scaber Stalk from unpolluted sites.


Reviews of Environmental Contamination and Toxicology | 2008

Arsenic in Marine Mammals, Seabirds, and Sea Turtles

Takashi Kunito; Reiji Kubota; Junko Fujihara; Tetsuro Agusa; Shinsuke Tanabe

Although there have been numerous studies on arsenic in low-trophic-level marine organisms, few studies exist on arsenic in marine mammals, seabirds, and sea turtles. Studies on arsenic species and their concentrations in these animals are needed to evaluate their possible health effects and to deepen our understanding of how arsenic behaves and cycles in marine ecosystems. Most arsenic in the livers of marine mammals, seabirds, and sea turtles is AB, but this form is absent or occurs at surprisingly low levels in the dugong. Although arsenic levels were low in marine mammals, some seabirds, and some sea turtles, the black-footed albatross and hawksbill and loggerhead turtles showed high concentrations, comparable to those in marine organisms at low trophic levels. Hence, these animals may have a specific mechanism for accumulating arsenic. Osmoregulation in these animals may play a role in the high accumulation of AB. Highly toxic inorganic arsenic is found in some seabirds and sea turtles, and some evidence suggests it may act as an endocrine disruptor, requiring new and more detailed studies for confirmation. Furthermore, DMA(V) and arsenosugars, which are commonly found in marine animals and marine algae, respectively, might pose risks to highly exposed animals because of their tendency to form reactive oxygen species. In marine mammals, arsenic is thought to be mainly stored in blubber as lipid-soluble arsenicals. Because marine mammals occupy the top levels of their food chain, work to characterize the lipid-soluble arsenicals and how they cycle in marine ecosystems is needed. These lipid-soluble arsenicals have DMA precursors, the exact structures of which remain to be determined. Because many more arsenicals are assumed to be present in the marine environment, further advances in analytical capabilities can and will provide useful future information on the transformation and cycling of arsenic in the marine environment.


Journal of Environmental Monitoring | 2006

Urinary 8-hydroxy-2'-deoxyguanosine in inhabitants chronically exposed to arsenic in groundwater in Cambodia.

Reiji Kubota; Takashi Kunito; Tetsuro Agusa; Junko Fujihara; In Monirith; Hisato Iwata; Annamalai Subramanian; Touch Seang Tana; Shinsuke Tanabe

Arsenic concentrations in hair and urine, and urinary levels of 8-hydroxy-2-deoxyguanosine (8-OHdG), a marker of oxidative DNA damage, were examined for inhabitants of the Mekong Basin in Kratie Province, Cambodia. Also, the arsenic levels of tube-well water were determined. Total arsenic concentrations in tube-well water ranged from <1 to 886 microg L(-1), and 44.8% of these exceeded the WHO drinking water guideline of 10 microg L(-1). Elevated levels of arsenic were observed in the human hair and urine, and also a significant positive correlation was observed between the concentrations in hair and urine. These results suggest that the inhabitants are chronically exposed to arsenic through drinking the tube-well water. Levels of urinary 8-OHdG were higher for the subjects with higher arsenic levels in hair and urine, suggesting that induction of oxidative DNA damage was caused by chronic exposure to arsenic in tube-well water for the inhabitants in Kratie Province. To our knowledge, this is the first report on the oxidative DNA damage caused by chronic exposure to arsenic in groundwater for the inhabitants in Cambodia.


Marine Pollution Bulletin | 2002

Chemical speciation of arsenic in the livers of higher trophic marine animals.

Reiji Kubota; Takashi Kunito; Shinsuke Tanabe

Concentrations of total arsenic and individual arsenic compounds were determined in livers of cetaceans (Dalls porpoise and short-finned pilot whale), pinnipeds (harp and ringed seals), sirenian (dugong), and sea turtles (green and loggerhead turtles) to characterize arsenic accumulation profiles in higher trophic marine animals. Hepatic arsenic concentrations in sea turtles were highest among the species examined. Chemical speciation of arsenic revealed that arsenobetaine was the major arsenic compound in almost all the species. In contrast, arsenobetaine was a minor constituent in dugong. Dimethylarsinic acid, methylarsonic acid, arsenocholine, tetramethylarsonium ion, arsenite, and an unidentified arsenic compound were also detected as minor constituents. However, the composition of arsenic compounds was different among these species. These results might reflect the differences in the metabolism of arsenic and/or the compositions of arsenic compounds in their preys. To our knowledge, this is the first report on the large variation in the composition of arsenic species in liver of marine mammals and sea turtles.


Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 2007

Selected elements of Poison Pax Paxillus involutus

J. Falandysz; Takashi Kunito; Reiji Kubota; Andrzej Brzostowski; Mazur A. Justyna; Shinsuke Tanabe

Concentrations of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Cs, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Se, Sb, Sr, V, Tl and Zn have been determined in the whole fruiting bodies as well as separately in caps and stalks of Poison Pax collected from three geographically distant sites across Poland. The elements were determined using ICP-MS, ICP-OES, HG-AAS and CV-AAS, respectively. Based on arithmetic mean and median values for Poison Pax specimens from the Leźno site the elements such as Ag, Co, Cr, Cs, Mn, Mo, K, Pb, Rb, Sb, Se, V and Tl occur at similar concentration both in the caps and stalks, while for Cd, Cu, Hg, Mg and Zn around two-fold greater concentrations were noted in caps than stalks (cap/stalk concentration quotient > 1). Cs, Cd, Ni and Rb occurred at much greater concentration in specimens collected from the K≪odzka Hollow in the Sudety Mountains when compared to the lowland site (Mann–Whitney U-test), and slightly greater values were noted also for Cr, Mo and Rb, while for Ca, Co, Mg and Mn were smaller The results provide useful environmental and biological baseline level of information for metallic elements of Poison Pax.

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