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The purpose of this work was to investigate the distribution of total arsenic (As) in Chlamys farreri (C. farreri) tissues and evaluate the effects of steaming practices on the As levels. The results indicated that viscera was the part with the highest As concentration (5.08 ± 0.08 mg/kg, wet weight (ww)) and the highest As content percentage (more than 33%) of raw scallops. With the increase of steaming time, although the trends of various tissues were not clear on aspect of As concentration (dry weight (dw)), compared with control groups, there were significantly declined (p

The effects of ambient fine particulate matter (PM2.5) exposure on blood pressure have been widely reported. However, there remains uncertainty regarding the underlying roles of particulate matter components. We aimed to investigate the association between ambient PM2.5 exposure and blood pressure, as well as the potential effects of trace metal(loid)s, in a repeated-measurement study that enrolled women of childbearing age. Our study included 35 participants from Hebei Province, China, each of whom was visited for five times. During each visit, we conducted questionnaire surveys, measured blood pressure, and collected blood. The daily PM2.5 exposure of participants was estimated according to their residential addresses using a spatiotemporal model that combined monitoring data with satellite measurements and chemical-transport model simulations. This model was used to calculate average PM2.5 concentrations in 1, 3, 7, 15, 30, and 60 days prior to each visit. Serum concentrations of various trace metal(loid)s were measured. A linear mixed-effects model was used to investigate associations among study variables. Overall, the mean (standard deviation) 60 days PM2.5 concentration over all five visits was 108.1(43.3) μg/m3. PM2.5 concentration was positively associated with both systolic and diastolic blood pressures. Likewise, ambient PM2.5 concentration was positively associated with serum concentrations of manganese and arsenic, and negatively associated with serum concentrations of nickel, tin, and chromium. Only the serum concentration of molybdenum was negatively associated with systolic blood pressure. We concluded that ambient PM2.5 exposure may contribute to elevated blood pressure, potentially by interfering with internal intake of various metal(loid)s in the human body.

The orpiment[As2S3(s)] is an important secondary mineral in the geochemical process of arsenic in the environment. The study upon orpiment dissolution is important to investigate the migration and transformation of arsenic in the environment. The environmental pH and sulfur content have vital influence on species changing and stability of arsenic species in orpiment. Here we analyzed the stable arsenic species of anoxic orpiment dissolution in sulfidic and the absence of sulfide solutions at neutral condition with simulation test via X-ray absorption near edge spectroscopy(XANES) and extended X-ray absorption fine structure(EXAFS). The results showed that orpiment dissolution contained a mixture of arsenite and thioarsenite species at neutral condition, and arsenic species in sulfidic solutions is mainly thioarsenic, while arsenic species in the absence of sulfide solutions is oxythioarsenic. The results of Linear Combination of Fits showed that arsenic species were arsenite (88. 2%) and thioarsenite(11. 8%) in sulfidic solutions, and there were arsenite (56. 3%) and thioarsenite(43. 7%) in the absence of sulfide solutions. Our results confirmed that the formation of arsenite was related to the total sulfur to total arsenic ratios, and the form of thioarsenite species could be enriched by increasing of the total sulfur to total arsenic ratio.

the sediments is the second pollution source to the water quality of river in mining area, in order to assess the pollution extent of the Shuangqiao River by anthropogenic activity, and establish the geochemical background values and the possible geochemical anomaly range, The authors use Lognormal distribution plots to study the Mercury, Chromium, Cadmium, Lead, Copper, Arsenic, Zinc and Iron dispersion in the fine sediments of the Shuangqiao River. The Lognormal distribution plots are applied to discriminate the geochemical background levels of eight heavy metals from the geochemical anomalies. The result shows that Mercury, Lead are the most heavily pollution which is related to anthropogenic activities, and the concluded geochemical background value is more reasonable than before.

An As(III)-imprinted chitosan resin (As-ICR) was successfully prepared to selectively remove arsenic from Laminaria japonica Aresch (LJA) juice. Batch adsorption experiments and column adsorption experiments were performed to evaluate the adsorption conditions, selectivity, and reusability. The results showed that the minimum total arsenic concentration of the juice was 4.16 mg/L at pH 6.0, 40 °C, with equilibrium time 4 h. The selectivity of As-ICR for arsenic was much higher than that of non-imprinted chitosan resin. As-ICR could be reused for 10 times with only about 13% regeneration loss. FTIR spectra demonstrated that the adsorption of As-ICR for arsenic occurred on amino and hydroxyl groups. Total arsenic concentration of the juice decreased significantly, while the other metal ions decreased except Zn2+ insignificantly. This suggests that As-ICR is a very promising sorbent for selective removal of arsenic from the juice.

Arsenic pollution seriously threatens human health and environment safety, being a very prominent environmental issue to be urgently solved in the world. In natural environment and soil systems, arsenic exists in complicated forms, but the plant arsenic poisoning is mainly from As(V) and As (III) exposure. As(V) can be absorbed by plant roots through Pi channel, and reduced rapidly to As(III) by arsenate reductase. As( III) can be transported into plants through NIP channel, and subsequently either transformed into methylated arsenic by arsenic methyltransferase or chelated with the thiol of GSH and PCs. These arsenic compounds can be sequestrated in root cell vacuoles or transported to plant aerial parts. Meanwhile, a part of absorbed arsenic can be discharged to external media. All of these can help to detoxify the arsenic in plants. This paper reviewed the latest research progress on the arsenic- resistance of crops, especially rice, with the focus on the mechanisms of As(V) and As(Ill) absorption and excretion, As(V) reduction, and As (II) methylation and chelation. The major topics of future research on arsenic toxicity were proposed.

The soil of 0-100 cm depth was collected from the wastewater-irrigated farmland in Zhangshi, Shenyang and was amended with low concentration of arsenic. Microbial-mediated speciation transformation and environmental behavior of arsenic were investigated with and without addition of sulfate. The results showed that without addition of sulfate, arsenate was significantly reduced and released into soil solution after eight days of anaerobic incubation. Above 70% of arsenic presented as arsenite. More arsenic was released from the soil of 20-40 cm depth with arsenite and total arsenicconcentration of 892.8 microg x L(-1) and 1 240.6 microg x L(-1) respectively. Compared with abiotic control, the amount of arsenic dissolved in hydrochloric acid decreased greatly in each layer of soil, moreover, almost all of arsenic was reduced to arsenite. Ferric iron was also significantly reduced to ferrous and released into soil solution simultaneously. The concentration of ferrous iron in soil solution was above 40 mg x L(-1) in solution and was 9.0-13.4 g x kg(-1) in soil solid. Above 50% of the iron dissolved in hydrochloric acid was presented as ferrous. This indicates that microbial reduction leads to reductive dissolution of iron oxides and transformation of mineral configuration in soil solid. The release of arsenic and iron was notably suppressed after addition of 10 mmol x L(-1) sulfate, with the concentration reduced by 50%. The amount of HCl-dissolvable arsenic in soil solid decreased by 50%, compared to the treatment without sulfate addition, which probably due to precipitation of arsenic sulfide. It is obvious that microbial reduction leads to reduction and release of arsenic when sulfate is absent. In the presence of sulfate, microbes may transform mobile arsenic into more stable species. Formation of arsenic sulfide mineral was probably the mechanism for arsenic fixation in soil by microbes.

Spatial distribution of heavy metals, arsenic and organic matter in recent sediments in the Hangzhou section of the Grand Canal and their relationships were analyzed. The results showed that the concentrations of heavy metals and organic matters varied widely along the canal, and the average geological accumulation factors decreased in the following orders: organic carbon(2.6), zinc(2.1), cadmium (2.0), copper(1.5), lead(1.1), nitrogen(0.9), mercury (0.8), phosphorus(0.4), arsenic(0.2) and chromium(0). Content of heavy metals and organic carbon in the top 10 cm layer were lower than that of lower layers, except for mercury and organic carbon in the S9 section. Contents of organic carbon in the top 50 cm layer of the mud sediments are significantly higher than those underneath. In the bottom mud layer, there is a concentration peak of the pollutants. In the mud sediments of the canal, cadmium mainly occurred in the Fe and Mn oxide fraction, copper in the organic fraction, lead in the Fe and Mn oxide fraction, and zinc in the carbonate and the Fe and Mn oxide fraction.