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Rare-earth elements in human colostrum milk Texte intégral
2017
Poniedziałek, Barbara | Rzymski, Paweł | Pięt, Małgorzata | Niedzielski, Przemysław | Mleczek, Mirosław | Wilczak, Maciej | Rzymski, Piotr
Rare-earth elements (REEs) are used in a growing number of applications, and their release to environment has increased over the decades. Knowledge of REEs in human milk and factors that could possibly influence their concentration is scarce. This study evaluated the concentrations of 16 REEs (Ce, Eu, Er, Gd, La, Nd, Pr, Sc, Sm, Dy, Ho, Lu, Tb, Tm, Y, and Yb) in human colostrum milk collected from Polish women (n = 100) with the ICP-OES technique. The concentrations (mean ± SD) of Pr (41.9 ± 13.2 μg L⁻¹), Nd (11.0 ± 4.0 μg L⁻¹), La (7.1 ± 5.2 μg L⁻¹), and Er (2.2 ± 0.8 μg L⁻¹) were found above detection limits. The total mean ± SD concentration of detected REEs was 60.9 ± 17.8 μg L⁻¹. Current smokers displayed significantly increased Nd concentrations compared to women who had never smoked. No other associations between REEs in colostrum milk and age, diet in pregnancy (food supplement use and frequency of fish, meat, and vegetable consumption) or place of living (urban/rural) were found. This study adds to general understanding of the occurrence and turnover of REEs in women and human fluids.
Afficher plus [+] Moins [-]Presence of active pharmaceutical ingredients in the continuum of surface and ground water used in drinking water production Texte intégral
2017
Ahkola, Heidi | Tuominen, Sirkku | Karlsson, Sanja | Perkola, Noora | Huttula, Timo | Saraperä, Sami | Artimo, Aki | Korpiharju, Taina | Äystö, Lauri | Fjäder, Päivi | Assmuth, Timo | Rosendahl, Kirsi | Nysten, Taina
Anthropogenic chemicals in surface water and groundwater cause concern especially when the water is used in drinking water production. Due to their continuous release or spill-over at waste water treatment plants, active pharmaceutical ingredients (APIs) are constantly present in aquatic environment and despite their low concentrations, APIs can still cause effects on the organisms. In the present study, Chemcatcher passive sampling was applied in surface water, surface water intake site, and groundwater observation wells to estimate whether the selected APIs are able to end up in drinking water supply through an artificial groundwater recharge system. The API concentrations measured in conventional wastewater, surface water, and groundwater grab samples were assessed with the results obtained with passive samplers. Out of the 25 APIs studied with passive sampling, four were observed in groundwater and 21 in surface water. This suggests that many anthropogenic APIs released to waste water proceed downstream and can be detectable in groundwater recharge. Chemcatcher passive samplers have previously been used in monitoring several harmful chemicals in surface and wastewaters, but the path of chemicals to groundwater has not been studied. This study provides novel information on the suitability of the Chemcatcher passive samplers for detecting APIs in groundwater wells.
Afficher plus [+] Moins [-]Toxic metal tolerance in native plant species grown in a vanadium mining area Texte intégral
2017
Aihemaiti, Aikelaimu | Jiang, Jianguo | Li, De’an | Li, Tianran | Zhang, Wenjie | Ding, Xutong
Vanadium (V) has been extensively mined in China and caused soil pollution in mining area. It has toxic effects on plants, animals and humans, posing potential health risks to communities that farm and graze cattle adjacent to the mining area. To evaluate in situ phytoremediation potentials of native plants, V, chromium, copper and zinc concentrations in roots and shoots were measured and the bioaccumulation (BAF) and translocation (TF) efficiencies were calculated. The results showed that Setaria viridis accumulated greater than 1000 mg kg⁻¹ V in its shoots and exhibited TF > 1 for V, Cr, Zn and BAF > 1 for Cu. The V accumulation amount in the roots of Kochia scoparia also surpassed 1000 mg kg⁻¹ and showed TF > 1 for Zn. Chenopodium album had BAF > 1 for V and Zn and Daucus carota showed TF > 1 for Cu. Eleusine indica presented strong tolerance and high metal accumulations. S. viridis is practical for in situ phytoextractions of V, Cr and Zn and phytostabilisation of Cu in V mining area. Other species had low potential use as phytoremediation plant at multi-metal polluted sites, but showed relatively strong resistance to V, Cr, Cu and Zn toxicity, can be used to vegetate the contaminated soils and stabilise toxic metals in V mining area.
Afficher plus [+] Moins [-]Evaluation of exposure to fluoride in child population of North Argentina Texte intégral
2017
Rocha, René Antonio | Calatayud, Marta | Devesa, Vicenta | Vélez, Dinoraz
Fluoride is an important element for humans. It inhibits initiation and progression of dental caries and stimulates bone formation. However, excessive intake may lead to the appearance of dental and/or skeletal fluorosis and a decrease in intellectual coefficient in child populations. This study evaluates exposure to fluoride in the child population of Chaco province (Argentina) by analysis of drinking water, food and its bioaccessible fraction (quantity of fluoride solubilised by gastrointestinal digestion and available for intestinal absorption) and urine as a biomarker of internal dose. The concentration of fluoride in drinking water varied between 0.050 and 4.6 mg L⁻¹, and 80% of the samples exceeded the WHO drinking-water guideline value (1.5 mg L⁻¹). Fluoride concentrations in food ranged between 0.80 and 3.0 mg kg⁻¹ fresh weight (fw), being lower in bioaccessible fraction (0.43–1.9 mg kg⁻¹, fw). On the basis of the consumption data declared for the young child population, fluoride intake varies between 4.1 and 6.5 mg day⁻¹, greater than the level recommended for this age group. Moreover, in some cases, concentrations of fluoride found in urine (0.62–8.9 mg L⁻¹) exceeded those reported in areas with declared fluorosis. All data obtained show the worrying situation of child population in this area of Argentina.
Afficher plus [+] Moins [-]Occupational and life-style factors-acquired mutagenicity in agric-workers of northeastern Brazil Texte intégral
2017
Chaves, Tatiana Vieira Souza | Islam, Muhammad Torequl | de Moraes, Manoel Odoríco | de Alencar, Marcus Vinícius Oliveira Barros | Gomes, Débora Cássia Vieira | de Carvalho, Rodrigo Mendes | Maluf, Sharbel Weider | de Moura do Amaral, Fabrício Pires | Paz, Márcia Fernanda Correia Jardim | Cerqueira, Gilberto Santos | Rolim, Hercília Maria Lins | de Castro e Sousa, João Marcelo | de Carvalho Melo-Cavalcante, Ana Amélia | de Moraes, Maria Elisabete Amaral
Pesticides are a complex mixture of chemicals used to protect crops from a number of pests and diseases. They have been considered as potential mutagenic agents. This study aims at evaluation of the mutagenic effect of pesticide exposure to agricultural workers through chromosomal aberrations (CA) and micronucleus (MN) assay in peripheral blood lymphocytes and oral mucosal cells, respectively. The exposed group was consisted with 97 farmers, while the control (un-exposed) group consisted of 55. The results showed a significant (p < 0.05) increase in frequency of CA and MN in the exposed group. Both CA and MN profiles were linked to a significant (p < 0.05) co-relation with the confounding factors such as smoking habits, alcohol, vegetables, tea/coffee, vitamins, and sweetener consumptions. More cytogenetic events were denoted in smoking and alcohol consumption as well as non-personal protective equipment (non-PPE) and low/no vegetables user farmers. In conclusion, a deficiency of dietary and medicaments-derived antioxidants, while consumption of alcohol and tobacco, as well as effects of radiation, heavy metal poisoning (especially from sweeteners), and non-PPE using habits, may contribute cytogenetic damage to the workers.
Afficher plus [+] Moins [-]An anoxic-aerobic system for simultaneous biodegradation of phenol and ammonia in a sequencing batch reactor Texte intégral
2017
Liu, Qifeng | Singh, V. P. (Vijay P.) | Fu, Zhimin | Wang, Jing | Hu, La
A laboratory-scale sequencing batch reactor (SBR) was investigated to treat artificial pretreated coal gasification wastewater that was mainly contained of ammonia and phenol. The efficiency of SBR fed with increasing phenol concentrations (from 150 to 300 mg l⁻¹) and the relationship among phenol, nitrogen removal, and the microbial community structure were evaluated. When the phenol feeding concentration was increased to about 300 mg l⁻¹, the removal efficiency was above 99.0%, demonstrating the robustness of phenol removal capacity. The study showed that most phenol was degraded in anoxic stage. The average removal efficiencies of ammonia and total nitrogen were 98.4 and 81.9%, respectively, with average NH₄ ⁺-N concentration of 107.5 mg l⁻¹ and COD/N 7.5. Low temperature caused sludge loss that led to the decreased performance. Increasing the temperature could not recover the performance effectively. The data from bacterial analysis revealed that Delftia, Hydrogenophaga, and unclassified Xanthomonadaceae played a significant role in phenol degradation before the temperature increase, while uncultured Syntrophococcus sp. and unclassified Rhodocyclaceae were responsible for phenol degradation after the temperature increase. These results imply that the SBR holds potential for the simultaneous removal of phenolic compounds and nitrogen through aerobic ammonia oxidation and anoxic denitrification with phenol as the co-organic carbon source.
Afficher plus [+] Moins [-]Mercury contamination, a potential threat to the globally endangered aquatic warbler Acrocephalus paludicola Texte intégral
2017
Pacyna, AnetaDorota | Martínez, CarlosZumalacárregui | Miguélez, David | Jiguet, Frédéric | Polkowska, Żaneta | Wojczulanis-Jakubas, Katarzyna
Mercury (Hg) contamination is considered a global concern for humans and wildlife, and although the number of studies dealing with that issue continues to increase, some taxonomic groups such as small passerine birds are largely understudied. In this paper, concentration of mercury in the aquatic warbler (Acrocephalus paludicola) feathers, a globally threatened passerine species, was examined. The concentration differences between two ages and sexes were investigated. The comparison of feathers taken on autumn migrants of two age categories act as a comparison of the species’ exposure within the two different areas (European breeding or African wintering grounds). The average Hg concentration for all sampled individuals [2.32 μg/g dw (range 0.38–12.76)] is relatively high, compared with values found in other passerine species. An age difference was found, with first-year individuals displaying higher mercury concentrations than adults. This indicates that birds are exposed to mercury pollution during the breeding season, i.e., in the continental floodplains of eastern Europe. The average Hg concentration in feathers grown on the breeding grounds was 3.88 ± 2.59 μg/g dw, closer to the critical value of 5 μg/g dw, which is considered to impair the health of individuals. The findings suggest that mercury pollution may constitute a threat so far neglected for the endangered aquatic warbler.
Afficher plus [+] Moins [-]High added-value products from the hydrothermal carbonisation of olive stones Texte intégral
2017
Borrero-López, A.M. | Fierro, V. | Jeder, A. | Ouederni, A. | Masson, E. | Celzard, A.
Olive stones (OS) were submitted to hydrothermal carbonisation (HTC) in order to evaluate the possibility of producing high added-value products, mainly furfural (FU) and 5-hydroxymethylfurfural (5-HMF) on one hand and hydrochars and carbons on the other hand. Temperature (160–240 °C), residence time (1–8 h), initial pH (1–5.5) and liquid/solid ratio (4–48 w/w) were systematically varied in order to study the main products and to optimise FU production. FU production yield up to 19.9 %, based on the hemicellulose content, was obtained. Other minor, but valuable, compounds such as 5-methylfurfural (5-MF) and some phenolic compounds were also produced. The hydrochar was carbonised at 900 °C, and the resultant carbon material was highly ultramicroporous with a peak of pore size distribution centred on 0.5 nm and a surface area as high as 1065 m² g⁻¹, typical of most carbon molecular sieves.
Afficher plus [+] Moins [-]Effect of cadmium on cytosine hydroxymethylation in gastropod hepatopancreas Texte intégral
2017
Nica, Dragos | Popescu, Cristina | Draghici, George | Privistirescu, Ionela | Suciu, Maria | Stöger, Reinhard
5-Hydroxymethylcytosine (5hmC) is an important, yet poorly understood epigenetic DNA modification, especially in invertebrates. Aberrant genome-wide 5hmC levels have been associated with cadmium (Cd) exposure in humans, but such information is lacking for invertebrate bioindicators. Here, we aimed to determine whether this epigenetic mark is present in DNA of the hepatopancreas of the land snail Cantareus aspersus and is responsive to Cd exposure. Adult snails were reared under laboratory conditions and exposed to graded amounts of dietary cadmium for 14 days. Weight gain was used as a sublethal endpoint, whereas survival as a lethal endpoint. Our results are the first to provide evidence for the presence of 5hmC in DNA of terrestrial mollusks; 5hmC levels are generally low with the measured values falling below 0.03%. This is also the first study to investigate the interplay of Cd with DNA hydroxymethylation levels in a non-human animal study system. Cadmium retention in the hepatopancreas of C. aspersus increased from a dietary Cd dose of 1 milligram per kilogram dry weight (mg/kg d. wt). For the same treatment, we identified the only significant elevation in percentage of samples with detectable 5hmC levels despite the lack of significant mortalities and changes in weight gain among treatment groups. These findings indicate that 5hmC is an epigenetic mark that may be responsive to Cd exposure, thereby opening a new aspect to invertebrate environmental epigenetics.
Afficher plus [+] Moins [-]Amoxicillin removal from aqueous solution using activated carbon prepared by chemical activation of olive stone Texte intégral
2017
Limousy, Lionel | Ghouma, Imen | Ouederni, Abdelmottaleb | Jeguirim, Mejdi
A chemical-activated carbon (CAC) was prepared by phosphoric acid activation of olive stone. The CAC was characterized using various analytical techniques and evaluated for the removal of amoxicillin from aqueous solutions under different operating conditions (initial concentration, 12.5–100 mg L⁻¹, temperature, 20–25 °C, contact time, 0–7000 min). The CAC characterization indicates that it is a microporous carbon with a specific surface area of 1174 m²/g and a pore volume of 0.46 cm³/g and contains essentially acidic functional groups. The adsorption tests indicated that 93 % of amoxicillin was removed at 20 °C for 25 mg L⁻¹ initial concentration. Moreover, it was found that adsorption capacity increased with contact time and temperature. Kinetic study shows that the highest correlation was obtained for the pseudo-second-order kinetic model, which confirms that the process of adsorption of amoxicillin is mainly chemisorption. Using the intraparticle diffusion model, the mechanism of the adsorption process was determined. The equilibrium data analysis showed that the Sips and Langmuir models fitted well the experimental data with maximal adsorption capacities of 67.7 and 57 mg/g, respectively, at 25 °C. The chemical-activated carbon of olive stones could be considered as an efficient adsorbent for amoxicillin removal from aqueous solutions.
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