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Removal of selenium containing algae by the bivalve Sinanodonta woodiana and the potential risk to human health Texto completo
2018
Zhou, Chuanqi | Huang, Jung-Chen | Liu, Fang | He, Shengbing | Zhou, Weili
Selenium (Se) is an essential micronutrient for animals and humans with a relatively narrow margin between nutritional essentiality and potential toxicity. Even though our previous studies have demonstrated algae could efficiently remove Se, mainly through volatilization, concern is raised about eco-risks posed by the remaining Se in algae. Here, Sinanodonta woodiana was investigated as a biofilter for the removal of Se-containing Chlorella vulgaris and for its potential risk to human health. Our results suggest filtration rates of S. woodiana were independent of Se levels in algal biomass, with a removal efficiency of between 60 and 78%. However, Se concentrations accumulated in mussels were significantly correlated with algal-borne Se levels, with a dietary assimilation efficiency ranging from 12% to 46%. Thus, a pilot biofiltration system was set up to assess uptake and depuration processes. The system was found to efficiently remove Se laden algae through the uptake by mussels, while 21% of Se in mussels could be depurated in 6 days. Among tissues, gills accumulated the highest Se concentration after assimilating algal-borne Se but shed Se compounds in the fastest pace during depuration. Health risks posed by consumption of mussels exposed to different sources of Se were further assessed. S. woodiana accumulated the highest Se concentration after exposure to waterborne SeMet, followed by dietary Se, selenite and control. The relatively higher Se levels were found in gills for all the treatments. After boiling, the most common method of cooking mussels, the greatest reduction in Se concentration occurred in mantle for the control and dietary Se groups and in muscle for the SeMet and selenite treatments. Therefore, within the safe limits, Se-containing mussels can be consumed as a dietary supplement. Overall, our research suggests incorporation of mussels into an algal treatment system can improve Se removal efficiency and also provide financial incentives for practitioners.
Mostrar más [+] Menos [-]Arsenic speciation and bioaccessibility in raw and cooked seafood: Influence of seafood species and gut microbiota Texto completo
2021
Fu, Yaqi | Yin, Naiyi | Cai, Xiaolin | Du, Huili | Wang, Pengfei | Sultana, Mst Sharmin | Sun, Guoxin | Cui, Yanshan
Seafood is an important source of arsenic (As) exposure for humans. In this study, 34 seafood samples (fishes, shellfishes, and seaweeds) collected from different markets in China were analysed for total and speciated As before and after boiling. Furthermore, the As bioaccessibility was also assessed using a physiologically based extraction test combined with the Simulator of Human Intestinal Microbial Ecosystems. The results showed that the total As (tAs) contents of seaweeds (raw: 44.12; boiled: 31.13, μg·g⁻¹ dw) were higher than those of shellfishes (raw: 8.34; boiled: 5.14, μg·g⁻¹ dw) and fishes (raw: 6.01; boiled: 3.25, μg·g⁻¹ dw). Boiling significantly decreased the As content by 22.24% for seaweeds, 32.27% for shellfishes, and 41.42% in fishes, respectively (p < 0.05). During in vitro digestion, the bioaccessibility of tAs and arsenobetaine (AsB) significantly varied between the investigated species of seafood samples in gastric (G) and small intestinal phases (I) (p < 0.05). Higher tAs bioaccessibility (G: 68.6%, I: 81.9%) were obtained in fishes than shellfishes (G: 40.9%, I: 52.5%) and seaweeds (G: 31%, I: 53.6%). However, there was no significant differences in colonic phase (C) (p > 0.05). With the effect of gut microbiota, arsenate (AsⅤ) was transformed into monomethylarsonic acid (MMA) and arsenite (AsⅢ) in C. Moreover, as for seaweeds, an unknown As compound was produced.
Mostrar más [+] Menos [-]Light absorption of organic carbon emitted from burning wood, charcoal, and kerosene in household cookstoves Texto completo
2018
Xie, Mingjie | Shen, Guofeng | Holder, Amara L. | Hays, Michael D. | Jetter, James J.
Household cookstove emissions are an important source of carbonaceous aerosols globally. The light-absorbing organic carbon (OC), also termed brown carbon (BrC), from cookstove emissions can impact the Earth's radiative balance, but is rarely investigated. In this work, PM2.5 filter samples were collected during combustion experiments with red oak wood, charcoal, and kerosene in a variety of cookstoves mainly at two water boiling test phases (cold start CS, hot start HS). Samples were extracted in methanol and extracts were examined using spectrophotometry. The mass absorption coefficients (MACλ, m2 g−1) at five wavelengths (365, 400, 450, 500, and 550 nm) were mostly inter-correlated and were used as a measurement proxy for BrC. The MAC365 for red oak combustion during the CS phase correlated strongly to the elemental carbon (EC)/OC mass ratio, indicating a dependency of BrC absorption on burn conditions. The emissions from cookstoves burning red oak have an average MACλ 2–6 times greater than those burning charcoal and kerosene, and around 3–4 times greater than that from biomass burning measured in previous studies. These results suggest that residential cookstove emissions could contribute largely to ambient BrC, and the simulation of BrC radiative forcing in climate models for biofuel combustion in cookstoves should be treated specifically and separated from open biomass burning.
Mostrar más [+] Menos [-]Using devitalized moss for active biomonitoring of water pollution Texto completo
2016
Debén, S. | Fernández, J.A. | Carballeira, A. | Aboal, J.R.
This paper presents the results of an experiment carried out for the first time in situ to select a treatment to devitalize mosses for use in active biomonitoring of water pollution. Three devitalizing treatments for the aquatic moss Fontinalis antipyretica were tested (i.e. oven-drying at 100 °C, oven-drying with a 50-80-100 °C temperature ramp, and boiling in water), and the effects of these on loss of material during exposure of the transplants and on the accumulation of different heavy metals and metalloids were determined. The suitability of using devitalized samples of the terrestrial moss Sphagnum denticulatum to biomonitor aquatic environments was also tested. The structure of mosses was altered in different ways by the devitalizing treatments. Devitalization by boiling water led to significantly less loss of material (p < 0.01) than the oven-drying treatments. However, devitalization by oven-drying with a temperature ramp yielded more stable results in relation to both loss of material and accumulation of elements. With the aim of standardizing the moss bag technique, the use of F. antipyretica devitalized by oven-drying with a temperature ramp is recommended, rather than other devitalization treatments or use of S. denticulatum.
Mostrar más [+] Menos [-]Identification of genotoxic compounds in crude oil using fractionation according to distillation, polarity and Kow Texto completo
2017
Park, Shin Yeong | Lee, Hyo Jin | Khim, Jong Seong | Kim, Gi Beum
We examined the degree of DNA damage caused by fractions of crude oil in accordance with the boiling points, polarity and log Kow. Relatively high DNA damage was observed in the aromatic fraction (290–330°C) and resin and polar fraction (350–400°C). The resin and polar fraction showed relatively high genotoxicity compared with the aliphatic and aromatic fraction at the 1–4 log Kow range. At the 6–7 log Kow range, the aromatic fraction showed relatively high DNA damage compared with the aliphatic and resin and polar fraction. In particular, every detailed fraction in accordance with the log Kow values (aliphatic and aromatic (310–320°C) and resins and polar fractions (370–380°C)) showed one or less than one DNA damage. However, the fractions before separation in accordance with log Kow values (aliphatic and aromatic (310–320°C) and resin and polar (370–380°C) fractions) showed high DNA damage. Thus, we confirm the synergistic action between the detailed compounds.
Mostrar más [+] Menos [-]Depletion and biodegradation of hydrocarbons in dispersions and emulsions of the Macondo 252 oil generated in an oil-on-seawater mesocosm flume basin Texto completo
2014
Brakstad, Odd G. | Daling, Per S. | Faksness, Liv-G. | Almås, Inger K. | Vang, Siv-H. | Syslak, Line | Leirvik, Frode
Physically and chemically (Corexit 9500) generated Macondo 252 oil dispersions, or emulsions (no Corexit), were prepared in an oil-on-seawater mesocosm flume basin at 30–32°C, and studies of oil compound depletion performed for up to 15days. The use of Corexit 9500 resulted in smaller median droplet size than in a physically generated dispersion. Rapid evaporation of low boiling point oil compounds (C⩽15) appeared in all the experiments. Biodegradation appeared to be an important depletion process for compounds with higher boiling points in the dispersions, but was negligible in the surface emulsions. While n-alkane biodegradation was faster in chemically than in physically dispersed oil no such differences were determined for 3- and 4-ring PAH compounds. In the oil dispersions prepared by Corexit 9500, increased cell concentrations, reduction in bacterial diversity, and a temporary abundance of bacteria containing an alkB gene were associated with oil biodegradation.
Mostrar más [+] Menos [-]Effect of cooking on total mercury content in Norway lobster and European hake and public health impact Texto completo
2016
Perugini, Monia | Zezza, Daniela | Tulini, Serena Maria Rita | Abete, Maria Cesarina | Monaco, Gabriella | Conte, Annamaria | Olivieri, Vincenzo | Amorena, Michele
The risk of Hg poisoning by eating seafood is considered real from the several international agencies that recommended, by fish consumption advisories, to pregnant women and young children to avoid or severely limit the consumption of the fish and shellfish with a high-range mercury levels. The analyses of two common species, European hake and Norway lobster, collected from an area of Central Adriatic Sea, reported high mercury levels in crustaceans. For Norway lobster total mercury exceeded, in six out of ten analysed pools, the recommended 0.5mg/kg wet weight European limit. Moreover the increased amount of Hg concentrations in Norway lobster cooked samples suggests the necessity to review current procedures of Hg control in food, considering also consumption habits of consumers. The Hg values found in all European hake samples are below the legal limits and, in this species, the boiling did not modify the concentrations in fish tissues.
Mostrar más [+] Menos [-]Heat processing effect of luteolin on anti-metastasis activity of human glioblastoma cells U87 Texto completo
2018
El Gueder, Dorra | Maatouk, Mouna | Kalboussi, Zahar | Daouefi, Zaineb | Chaaban, Hind | Ioannou, Irina | Ghedira, Kamel | Ghedira, Leila Chekir | Luis, José
Among the flavonoïds, luteolin is a flavone that has been identified in many plants. It is known for its apoptotic potential with damage to DNA and cell cycle blockage. Many studies have shown that luteolin has anti-oxidant, anti-inflammatory, and anti-cancer activities. However, it is known that heat treatment (boiling, cooking, and treating with microwaves …) can influence the structure of flavonoïds, which often leads to changes in their activities. The present study was conducted to study the effect of heated luteolin on anti-tumor activity of glioblastoma cells U87. Glioblastoma cell viability was evaluated by MTT assay. Adhesion assay was performed on different protein matrices (collagen type 1, vitronectin, fibronectin, and poly-L-lysine); migration assay was determined by modified Boyden chambers and videomicroscopy, and finally, angiogenesis was tested in vitro by capillary network formation on Matrigel™. The results obtained show that the thermal treatment significantly reduces its cytotoxic activity and ability to inhibit cell adhesion to different protein matrices. It was also found that the heat processed significantly reduced the ability of luteolin to inhibit cell migration, cell invasion, and endothelial cell angiogenesis (HMEC-1). This suggests that heat treated luteolin has a lower anti-tumor potential than native luteolin. Graphical abstract ᅟ
Mostrar más [+] Menos [-]Dynamic modelling for cork boiling wastewater treatment at pilot plant scale Texto completo
2014
De Torres-Socías, E. | Cabrera-Reina, A. | Trinidad, M. J. | Yuste, F. J. | Oller, I. | Malato, S.
Solar photo-Fenton process has been extensively reported to be highly efficient in the remediation of complex industrial wastewater containing several families of pollutants such as pharmaceuticals, dyes, pesticides, derivatives of wine, etc. Moreover, solar photo-Fenton mathematical modelling regarded as a powerful tool for scaling-up and process control purposes is hindered by the complexity and variability of its reaction mechanism which depends on the particular wastewater under study. In this work, non-biodegradable cork boiling wastewater has been selected as a case study for solar photo-Fenton dynamic modelling by using MATLAB® software. First of all physic-chemical pretreatment was applied attaining chemical oxygen demand (COD) reductions between 43 and 70 % and total suspended solid (TSS) reductions between 23 % and 59 %. After solar photo-Fenton treatment, COD decreased between 45 and 90 % after consumptions of H₂O₂ varying around 1.9 and 2.4 g/L. Individual calibration of the semi-empirical model by using experimental results made it possible to perfectly predict hydrogen peroxide variations throughout the treatment. It must be highlighted that slight deviations between predictions and experimental data must be attributed to important changes in wastewater characteristics.
Mostrar más [+] Menos [-]Effect of cooking on arsenic concentration in rice Texto completo
2020
Atiaga, Oliva | Nunes, Luis M. | Otero, Xosé L.
This study assessed the effect of rinsing and boiling on total content of As (tAs) and of its inorganic and organic forms in different types of rice (polished and brown) from Spain and Ecuador. Rice was subjected to five different treatments. The results showed that the treatment consisting of three grain rinsing cycles followed by boiling in excess water showed a significant decrease in tAs content compared with raw rice. Regarding As species, it is worth noting that the different treatments significantly reduced the content of the most toxic forms of As. The estimated lifetime health risks indicate that pre-rinsing alone can reduce the risk by 50%, while combining it with discarding excess water can reduce the risk by 83%; therefore, the latter would be the preferable method.
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