Distribution Of Arsenic Compounds Research Articles

Arsenic Trioxide Therapy During Pregnancy: ATO and Its Metabolites in Maternal Blood and Amniotic Fluid of Acute Promyelocytic Leukemia Patients.

Acute promyelocytic leukemia (APL) is extremely fatal if treatment is delayed. Management of APL in pregnancy is a challenging situation. Arsenic trioxide (ATO) is successfully applied to treat APL. ATO can be transformed into different arsenic species [arsenite (AsIII), monomethylated arsenic (MMA, consists of MMAIII and MMAV), dimethylated arsenic (DMA, consists of DMAIII and DMAV), and arsenate (AsV)], which produce different toxic effects. Investigating the maternal and fetal exposure to arsenic species is critical in terms of assessing maternal and fetal outcomes, choice of optimal treatment, and making decisions for attempting to preserve the obstetrical and fetal wellbeing. In this study, maternal blood and amniotic fluid (AF) from APL patients treated with ATO in pregnancy and blood samples of non-pregnant patients were collected. Concentrations of inorganic arsenic (iAs, iAs = AsIII+AsV), MMA, and DMA were analyzed by high-performance liquid chromatography–hydride generation–atomic fluorescence spectrometry (HPLC–HG–AFS). The difference in arsenic species of plasma between pregnant patients and non-pregnant patients, distribution of arsenic compounds in AF and maternal plasma, and arsenic penetration into AF were explored. The outcomes of pregnant women treated with ATO and their fetus were analyzed. No significant differences in arsenic concentration, percentage, and methylation index [PMI: primary methylation index (MMA/iAs); SMI: secondary methylation index (DMA/MMA)] between pregnant women and non-pregnant women (p > 0.05) were observed. The mean ratios of AF to maternal plasma were as follows: iAs, 2.09; DMA, 1.04; MMA, 0.49; and tAs, 0.98. Abortion rate is higher with the diagnosis at an earlier gestational age, with 0%, 67%, and 100% of pregnancies ending in abortion during the third, second, and first trimester, respectively. The age of the pregnant women, the dose of ATO, and the duration of fetal exposure in utero had no influence on fetal outcomes. All APL women achieved complete remission (CR). Collectively, ATO and its metabolites can easily cross the placenta. Levels and distribution of arsenic species in maternal plasma and AF gave evidence that arsenic species had a different ability to penetrate the placenta into AF (iAs > DMA > MMA) and indicated a relatively high fetal exposure to ATO and its metabolites in utero. Gestational age at diagnosis was more likely to be closely related to fetal outcomes, but had no effects on mother outcomes.

Distribution of arsenic compounds in Plantaginaceae and Cyperaceae plants growing in contaminated soil

ABSTRACTThe ability of plant species to accumulate arsenic (As) species in the biomass from As-contaminated soils is variable. Among the plants widely grown at the As-contaminated locations, Plantaginaceae and Cyperaceae families belong to the frequent ones. In this study, the ability of Plantago lanceolata (Plantaginaceae) and three wetland plant species representing the family Cyperaceae (Carex praecox, Carex vesicaria, and Scirpus sylvaticus) naturally occurring in the soils with an elevated As in the Czech Republic were investigated. The plants were cultivated under controlled conditions in an As-contaminated soil reaching 735 mg kg−1 of the total As. The total As in plants reached up to 8.3 mg kg−1 in leaves, and up to 155 mg kg−1 in roots of C. praecox. Dominant As compounds were arsenite and arsenate with a small abundance of dimethylarsinic acid (DMA) in all the plant species. In Cyperaceae, small percentages of arsenobetaine (AB) and arsenocholine (AC) were detected, suggesting the ability of these plants to transform As into less toxic compounds. Moreover, the important role of As(V) sequestration on iron plaque on the root surface of Cyperaceae was confirmed. In this context, root washing with oxalic acid partially disrupted the iron plaque for the better release of arsenate.

Stability of arsenic species in hydroponic media and its influence on arsenic uptake and distribution in White mustard (Sinapis alba L.)

The long-term uptake and distribution of arsenic compounds by hydroponically cultivated White mustard (Sinapis alba) was investigated with a special emphasis on controlling the stability of the arsenic compounds in nutrient solution during the experiment. It was concluded that arsenites are rapidly oxidised to arsenates during the 7-day cultivation of White mustard. The presence of plant roots increases the oxidation rate of arsenites. Dimethylarsinic acid (DMA) and arsenates remain stable during the exposition, while monomethylarsonic acid (MMA) is partially demethylated. When the nutrient solution containing arsenites is exchanged daily, the distribution of arsenic in White mustard is significantly different (translocation factor—TF—is 70 times higher) in comparison to the experiment without exchange of the medium. Speciation analysis of arsenic in plant tissues and in nutrient solutions was performed by high performance liquid chromatography with inductively coupled plasma-mass spectrometry (HPLC ICP-MS). The results obtained unquestionably illustrated that the uncontrolled conditions of hydroponic plant cultivation may be a source of misinterpretation of all the obtained data. Additionally, the synthesis of phytochelatins in plants exposed to different arsenic compounds was investigated. Phytochelatins were identified in tissues of plants exposed to arsenites and arsenates, and their presence was correlated with high arsenite content. Phytochelatin synthesis was not indicated in plants grown in the presence of MMA and DMA.

Intake and excretion of arsenicals in green (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata)

Environmental context Although among higher marine animals, relatively high concentration of arsenic and unique distribution of arsenic compounds are found in green (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata), the accumulation mechanism remains unknown. We examined the accumulation of arsenicals in two turtles from the standpoint of short- and long-term intake and excretion and found that prey items might be important for the arsenic accumulation. This study can provide useful information on the accumulation pattern of arsenic speciation in sea turtles. Abstract We analysed arsenic (As) compounds in the stomach and intestine contents, bile and urine of green (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) to understand As accumulation through intake and excretion. Stable isotopes of δ15N and δ13C were also measured for understanding the feeding behaviour dependent accumulation of As. Major As species in gastrointestinal contents were unknown water-soluble As, followed by unextracted As. Concentrations of AB and DMA in the tissues were higher than those in the stomach contents (prey items), indicating high bioaccumulation of these arsenicals. In green turtles, AB concentration was high in bile and increased throughout the gastrointestinal tract, suggesting significant biliary excretion of AB. δ15N was positively correlated with AB level in green turtles, whereas a negative relationship between residual As and δ15N was observed in hawksbill turtles. This study indicates feeding behaviour-dependent accumulation of As compounds in both turtle species for the first time.

Distribution of arsenic compounds in Mytilus galloprovincialis of the Venice lagoon (Italy)

Samples of Mytilus galloprovincialis collected in different sites of the Venice lagoon (Italy) were investigated for total arsenic concentrations by ICP-AES and for single arsenic species by HPLC-ICP-MS. For this purpose, an analytical procedure for the sensitive and efficient speciation of the arsenic species As(III), As(V), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AB), arsenocholine (AC), and four arsenosugars was optimised. The total arsenic and the single arsenic species were determined in both the hepatopancreas (digestive gland) and the remaining soft tissues in order to verify the different arsenic accumulation in the body parts of mussels. Arsenic compounds were extracted from the mussels with a methanol/water mixture; the extracts were evaporated to dryness, redissolved in water, and chromatographed in an anion-exchange column, a Hamilton PRP-X100. Only small quantities or traces of inorganic arsenic were detected in the mussels. The majority of arsenic compounds detected in the extracts were organic species, with a predominance of arsenobetaine and of an arsenosugar. In addition, a greater arsenic accumulation in the digestive glands of mussels was observed.

Arsenic uptake and arsenic compounds in cultivated Agaricus bisporus

In view of recent findings that most wild-growing mushrooms contain mainly organo-arsenic compounds, this work was conducted as a preliminary study of arsenic uptake and the distribution of arsenic compounds in mushrooms grown under controlled conditions with the intention of assessing potential health risks involved in the consumption of cultivated Agaricus bisporus. Agaricus bisporus was grown on substrate containing 1000 mg As kg −1 As(V) as well as on control substrate without arsenic addition. Agaricus bisporus grown on the control substrate (3.8 ± 0.2 μg As/g dry mass) contained 0.50 ± 0.03 μg As/g dry mass, whereas 22.8 ± 1.0 μg As/g dry mass were found in the mushrooms grown on the substrate amended with As(V). Arsenic speciation analysis of extracts of the mushrooms revealed that the main proportion of the incorporated arsenic in the treated Agaricus bisporus was present as inorganic arsenic. In the treated mushrooms the concentration of dimethylarsinic acid was twice as high as in the control mushrooms and the concentration of methylarsonic acid was almost 4 times higher than the concentration in the control mushrooms. Surprisingly, the concentration of arsenobetaine in the treated mushrooms was approximately half the concentration in the control sample.

Tissue accumulation and distribution of arsenic compounds in three marine fish species: relationship to trophic position

AbstractIn this study the accumulation and distribution of arsenic compounds in marine fish species in relation to their trophic position was investigated. Arsenic compounds were measured in eight tissues of mullet Mugil cephalus (detritivore), luderick Girella tricuspidata (herbivore) and tailor Pomatomus saltatrix (carnivore) by high performance liquid chromatography–inductively coupled plasma‐mass spectrometry. The majority of arsenic in tailor tissues, the pelagic carnivore, was present as arsenobetaine (86–94%). Mullet and luderick also contained high amounts of arsenobetaine in all tissues (62–98% and 59–100% respectively) except the intestines (20% and 24% respectively). Appreciable amounts of dimethylarsinic acid (1–39%), arsenate (2–38%), arsenite (1–9%) and trimethylarsine oxide (2–8%) were identified in mullet and luderick tissues. Small amounts of arsenocholine (1–3%), methylarsonic acid (1–3%) and tetramethylarsonium ion (1–2%) were found in some tissues of all three species. A phosphate arsenoriboside was identified in mullet intestine (4%) and from all tissues of luderick (1–6%) except muscle. Pelagic carnivore fish species are exposed mainly to arsenobetaine through their diet and accumulate the majority of arsenic in tissues as this compound. Detritivore and herbivore fish species also accumulate arsenobetaine from their diet, with quantities of other inorganic and organic arsenic compounds. These compounds may result from ingestion of food and sediment, degradation products (e.g. arsenobetaine to trimethylarsine oxide; arsenoribosides to dimethylarsinic acid), conversion (e.g. arsenate to dimethylarsinic acid and trimethylarsine oxide by bacterial action in digestive tissues) and/or in situ enzymatic activity in liver tissue. Copyright © 2001 John Wiley & Sons, Ltd.

Occurrence and chemical form of arsenic in marine macroalgae from the east coast of Australia

Arsenic concentrations were measured in thirteen macroalgal species from Sydney, Australia. Brown macroalgae contained, on average, more arsenic (range, mean ± s.e.: 5–173 μg g–1, 39 ± 4 μg g–1) than either green (0.12–30.2 μg g–1, 10.7 ± 0.7 μg g–1) or red macroalgae (0.11–16.9 μg g–1, 4.3 ± 0.3 μg g–1). Despite the overlap in arsenic concentrations between different macroalgal species, inter-species arsenic variation was apparent with arsenic concentrations following the order brown > green > red macroalgal species. It was concluded that the main contribution to the variation in arsenic concentration was from natural variability expected to occur between individuals of any species as a result of physiological differences.Most of the arsenic compounds in macroalgae (70–108%) could be extracted using methanol/water mixtures, with 38–95% of the arsenic compounds present in characterizable forms. All macroalgal species contained arsenoribosides (9–99%). The distribution of arsenoribosides followed a general pattern; glycerol-arsenoriboside and phosphate-arsenoriboside were common to all macroalgal species. Sulfonate-arsenoriboside and sulfate-arsenoriboside were found in brown macroalgal species and one red macroalgal species. Six macroalgal species contained high concentrations of inorganic arsenic (14.2–62.9%) and four species contained high concentrations of dimethylarsinic acid (13.3–41.1%). The variation in the distribution of arsenic compounds in marine macroalgal species appears to be related to taxonomic differences in storage and structural polysaccharides.

The Distribution of Arsenic Compounds in the Ocean: Biological Activity in the Surface Zone and Removal Processes in the Deep Zone

The vertical profies of inorganic arsenic [As(III) + As(V)], monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA) were investigated at four sampling stations in the Pacific Ocean and a sampling station in the southern Tasman Sea. In addition, the concentrations of those compounds in surface waters of the Pacific Ocean and Tasman Sea have been determined. The vertical profiles of inorganic arsenic showed the low concentrations in both the surface and deep/bottom zones. The depleted concentrations in the surface zone varied from 1000 to 1700 ng dm -3 and that in the deep/bottom zone varied from 1300 to 2050 ng dm -3 . The maximum concentrations that varied from 1500 to 2450 ng dm -3 were usually observed at a depth of about 2000 m. Both MMAA and DMAA were observed throughout the water column at sampling stations in the north-western and equatorial regions of the Pacific Ocean. At the sampling station in the central northern Pacific gyre, DMAA was the only methylated arsenic compound observed throughout the water column. On the contrary, at the sampling station in the southern Tasman Sea, the only detected methylated arsenic compound throughout the water column was MMAA. Their vertical profiles showed maximum concentrations in the surface water which abruptly dropped with depth from 0 to 200 m. The concentration in the surface water was close to 10 ng dm -3 for MMAA and varied from 27 to 185 ng dm -3 for DMAA. At depths greater than 100 m, MMAA and DMAA were at comparable concentrations which varied from 0.7 to 14 ng dm -3 . The low inorganic arsenic concentration in the surface zone was due to biological activity. This activity resulted in the uptake of As(V) and subsequent reduction and methylation to MMAA and DMAA. DMAA was the main predominant arsenic compound resulting from biological activity in surface waters. The low inorganic arsenic concentrations in the deep and bottom zones were likely to be caused by the adsorption of dissolved inorganic arsenic onto sinking particulates rich in iron and manganese oxides.