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Cadmium distribution in mature durum wheat grains using dissection, laser ablation-ICP-MS and synchrotron techniques * Полный текст
2020
Yan, Bofang | Isaure, Marie-Pierre | Mounicou, Sandra | Castillo-Michel, Hiram | De Nolf, Wout | Nguyen, Christophe | Cornu, Jean-Yves
Understanding how essential and toxic elements are distributed in cereal grains is a key to improving the nutritional quality of cereal-based products. The main objective of this work was to characterize the distribution of Cd and of nutrients (notably Cu, Fe, Mn, P, S and Zn) in the durum wheat grain. Laser ablation inductively coupled mass spectrometry and synchrotron micro X-ray fluorescence were used for micro-scale mapping of Cd and nutrients. A dissection approach was used to quantitatively assess the distribution of Cd and nutrients among grain tissues. Micro X-ray absorption near-edge spectroscopy was used to identify the Cd chemical environment in the crease. Cadmium distribution was characterized by strong accumulation in the crease and by non-negligible dissemination in the endosperm. Inside the crease, Cd accumulated most in the pigment strand where it was mainly associated with sulfur ligands. High-resolution maps highlighted very specific accumulation areas of some nutrients in the germ, for instance Mo in the root cortex primordia and Cu in the scutellum. Cadmium loading into the grain appears to be highly restricted. In the grain, Cd co-localized with several nutrients, notably Mn and Zn, which challenges the idea of selectively removing Cd-enriched fractions by dedicated milling process.
Показать больше [+] Меньше [-]First measurement of human exposure to current use pesticides (CUPs) in the atmosphere of central Chile: The case study of Mauco cohort Полный текст
2020
Cortés, Sandra | Pozo, Karla | Llanos, Yasna | Martínez, Natalia | Foerster, Claudia | Leiva, Cinthya | Ustáriz, Javier | Přibylová, Petra | Klánová, Jana | Jorquera, Héctor
Chile is a leading agricultural producer and thus consumer of insecticides, herbicides, and fungicides. In Molina, Central Chile, a prospective cohort has been established for studying the incidence and risk factors of chronic diseases in the adult population. Our goals were to measure airborne current use pesticides (CUPs), assess their spatial distribution and potential sources, and estimate health risks for the population in Molina. CUPs were measured using passive air samplers (PAS), deployed on six sites from October 2015 to August 2016. Thirty-eight pesticides were analyzed using high performance liquid chromatography (HPLC), but only nine of them were detected. Chlorpyrifos (CPF) was detected with air concentrations ranging from 444 to 14 624 (pg m(-3)). Diazinon, atrazine, dimethoate, metolachlor, simazine, terbuthylazine and tebuconazole were also detected; only pendimethalin had concentrations as high as those of CPF, with a maximum of 14 927 (pg m(-3)). Backward wind trajectories were used to estimate locations of potential sources contributing to airborne CUPs concentrations. Most of the exposure to CUPs was associated with local sources, while regional sources southern/eastern/western of Molina appear to contribute as secondary sources (soil evaporation followed by atmospheric transport) in spring and summer seasons. A health risk assessment using US-EPA's methodology was carried out for inhalation exposure of detected pesticides. None of the measured CUPs were associated with a hazard quotient (HQ) greater than 1, indicating no significant risk due to inhalation of pesticides in Molina's population with the exception of the group of children below 12 years old. However, further investigations are needed to evaluate others CUPs exposure route such as food consumption and dermal exposure to improve our health risk estimations. | Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) 15130011-15110020 180078 1161673 Vicerrectoria de Investigacion, Pontificia Universidad Catolica de Chile 9/2014 RECETOX Research Infrastructure LM2015051 CZ.02.1.01/0.0/0.0/16_013/0001761
Показать больше [+] Меньше [-]Development of a flux DMT with integrated adsorptive stripping voltammetry for free metal ions detection in solution Полный текст
2018
Janot, Noemie | Rotureau, Elise | Pinheiro, Jose Paulo
Development of a flux DMT with integrated adsorptive stripping voltammetry for free metal ions detection in solution. Interfaces Against Pollution
Показать больше [+] Меньше [-]Ecotoxicoproteomic assessment of the functional alterations caused by chronic metallic exposures in gammarids Полный текст
2017
Gismondi, Eric | Thomé, Jean-Pierre | Urien, Nastassia | Uher, Emmanuelle | Baiwir, Dominique | Mazzucchelli, Gabriel | De Pauw, Edwin | Fechner, Lise | Lebrun, Jérémie | FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
peer reviewed | Very few ecotoxicological studies have been performed on long-term exposure under controlled conditions, hence limiting the assessment of the impact of chronic and diffuse chemical pressures on the health of aquatic organisms. In this study, an ecotoxicoproteomic approach was used to assess the integrated response and possible acclimation mechanisms in Gammarus fossarum following chronic exposures to Cd, Cu or Pb, at environmentally realistic concentrations (i.e. 0.25, 1.5 and 5 µg/L respectively). After 10-week exposure, changes in protein expression were investigated in caeca of control and exposed males. Gel-free proteomic analyses allowed for the identification of 35 proteins involved in various biological functions, for which 23 were significantly deregulated by metal exposures. The protein deregulation profiles were specific to each metal, providing evidence for metal-specific action sites and responses of gammarids. Among the tested metals, Cu was the most toxic in terms of mortality, probably linked with persistent oxidative stress. Moulting and osmoregulation were the major biological functions affected by Cu in the long-term. In Pb-exposed gammarids, significant deregulations of proteins involved in immune response and cytoskeleton were observed. Reproduction appears to be strongly affected in gammarids chronically exposed to Cd or Pb. Besides, modified expressions of several proteins involved in energy transfer and metabolism highlighted important energetic reshuffling to cope with chronic metal exposures. These results support the fact that metallic pressures induce a functional and energetic cost for individuals of G. fossarum with potential repercussions on population dynamics. Furthermore, this ecotoxicoproteomic study offers promising lines of enquiry in the development of new biomarkers that could make evidence of long-term impacts of metals on the health of organisms.
Показать больше [+] Меньше [-]A review on occurrence of emerging pollutants in waters of the MENA region Полный текст
2021
Haddaoui, I. | Mateo-Sagasta, Javier
Little is known about the occurrence of emerging pollutants (EPs) in waters in the Middle East and North Africa (MENA) region despite the extensive use of low-quality water there. Available data dealing with the sources, occurrence and removal of EPs within the MENA region in different categories of water is collected, presented and analyzed in this literature review. According to the collected database, the occurrence and removal efficiency of EPs in the water matrix in the MENA region is available, respectively, for 13 and six countries of the 18 in total; no available data is registered for the rest. Altogether, 290 EPs have been observed in different water matrices across the MENA countries, stemming mainly from industrial effluents, agricultural practices, and discharge or reuse of treated wastewater (TWW). Pharmaceutical compounds figure among the most frequently reported compounds in wastewater, TWW, surface water, and drinking water. Nevertheless, pesticides are the most frequently detected pollutants in groundwater. Worryingly, 57 cases of EPs have been reported in different fresh and drinking waters, exceeding World Health Organization (WHO) and European Commission (EC) thresholds. Overall, pharmaceuticals, organic compounds, and pesticides are the most concerning EP groups. The review revealed the ineffectiveness of treatment processes used in the region to remove EPs. Negative removals of some EPs such as carbamazepine, erythromycin, and sulfamethoxazole were recorded, suggesting their possible accumulation or release during treatment. This underlines the need to set in place and strengthen control measures, treatment procedures, standards, and policies for such pollutants in the region.
Показать больше [+] Меньше [-]Temporal changes in environmental health risks and socio-psychological status in areas affected by the 2011 tsunami in Ishinomaki, Japan Полный текст
2013
Makita, K. | Inoshita, K. | Kayano, T. | Uenoyama, K. | Hagiwara, K. | Asakawa, M. | Ogawa, K. | Kawamura, S. | Noda, J. | Sera, K. | Sasaki, H. | Nakatani, N. | Higuchi, H. | Ishikawa, N. | Iwano, H. | Tamura, Y.
On March 11 2011, a tsunami caused by a magnitude 9.0 earthquake devastated the northeastern coast of Honshu, Japan.The present study was conducted to assess environmental health risks of the areas affected and socio-psychological status of the dislocated people in Ishinomaki. Samples of sludge, water, flies and rodents were collected in 20 urban neighborhood associations affected by the tsunami in July and August 2011, and in August 2012. A socio-psychological survey was conducted in two urban and one rural temporary housing complexes in 2012. Animal feed concentrates and fish from damaged factories were scattered along the coast which caused a strong odor and great number of flies. Removal of fish and feed along with spraying insecticides reduced the odor and the number of flies by August 2011. The sludge and water samples contained potentially hazardous bacteria, but none were highly pathogenic. Heavy metals in sludge were not in alarming quantities. A rodent was captured in one unit in August 2011, and monitoring in two units found that the log number of rodents captured increased significantly over time (slope=0.08, p = 0.005). In temporary housing complexes, those who originally lived in rural fishing villages wished to return to their homes more (64.2%, 9/14) than in urban areas (30.6%, 11/36, p = 0.06). Risk factors for depression included absence of friends (p = 0.011) or trusted person to counsel in the housing complexes (p = 0.003) and illness of the respondent or a family member (p = 0.003). In conclusion, overall environmental health risk was acceptable for living, and monitoring of rodents population was recommended. In addition, psychological and economical support was needed for evacuees in temporary housing complexes.
Показать больше [+] Меньше [-]An ex ante life cycle assessment of wheat with high biological nitrification inhibition capacity Полный текст
2022
Leon, Ai | Guntur Venkata Subbarao | Kishii, Masahiro | Naruo Matsumoto | Kruseman, Gideon K.
It is essential to increase food production to meet the projected population increase while reducing environmental loads. Biological nitrification inhibition (BNI)-enabled wheat genetic stocks are under development through chromosome engineering by transferring chromosomal regions carrying the BNI trait from a wild relative (Leymus racemosus (Lam.) Tzvelev) into elite wheat varieties; field evaluation of these newly developed BNI-wheat varieties has started. Ten years from now, BNI-enabled elite wheat varieties are expected to be deployed in wheat production systems. This study aims to evaluate the impacts of introducing these novel genetic solutions on life cycle greenhouse gas (LC-GHG) emissions, nitrogen (N) fertilizer application rates and N-use efficiency (NUE). Scenarios were developed based on evidence of nitrification inhibition and nitrous oxide (N2O) emission reduction by BNI crops and by synthetic nitrification inhibitors (SNIs), as both BNI-wheat and SNIs slow the nitrification process. Scenarios including BNI-wheat will inhibit nitrification by 30% by 2030 and 40% by 2050. It was assumed that N fertilizer application rates can potentially be reduced, as N losses through N2O emissions, leaching and runoff are expected to be lower. The results show that the impacts from BNI-wheat with 40% nitrification inhibition by 2050 are assessed to be positive: a 15.0% reduction in N fertilization, a 15.9% reduction in LC-GHG emissions, and a 16.7% improvement in NUE at the farm level. An increase in ammonia volatilization had little influence on the reduction in LC-GHG emissions. The GHG emissions associated with N fertilizer production and soil N2O emissions can be reduced between 7.3 and 9.5% across the wheat-harvested area worldwide by BNI-wheat with 30% and 40% nitrification inhibition, respectively. However, the present study recommends further technological developments (e.g. further developments in BNI-wheat and the development of more powerful SNIs) to reduce environmental impacts while improving wheat production to meet the increasing worldwide demand.
Показать больше [+] Меньше [-]Fluoride in weathered rock aquifers of southern India: managed aquifer recharge for mitigation Полный текст
2016
Brindha, Karthikeyan | Jagadeshan, G. | Kalpana, L. | Elango, L.
Climatic condition, geology, and geochemical processes in an area play a major role on groundwater quality. Impact of these on the fluoride content of groundwater was studied in three regions-part of Nalgonda district in Telangana, Pambar River basin, and Vaniyar River basin in Tamil Nadu, southern India, which experience semi-arid climate and are predominantly made of Precambrian rocks. High concentration of fluoride in groundwater above 4 mg/l was recorded. Human exposure dose for fluoride through groundwater was higher in Nalgonda than the other areas. With evaporation and rainfall being one of the major contributors for high fluoride apart from the weathering of fluoride rich minerals from rocks, the effect of increase in groundwater level on fluoride concentration was studied. This study reveals that groundwater in shallow environment of all three regions shows dilution effect due to rainfall recharge. Suitable managed aquifer recharge (MAR) methods can be adopted to dilute the fluoride rich groundwater in such regions which is explained with two case studies. However, in deep groundwater, increase in fluoride concentration with increase in groundwater level due to leaching of fluoride rich salts from the unsaturated zone was observed. Occurrence of fluoride above 1.5 mg/l was more in areas with deeper groundwater environment. Hence, practicing MAR in these regions will increase the fluoride content in groundwater and so physica or chemical treatment has to be adopted. This study brought out the fact that MAR cannot be practiced in all regions for dilution of ions in groundwater and that it is essential to analyze the fluctuation in groundwater level and the fluoride content before suggesting it as a suitable solution. Also, this study emphasizes that long-term monitoring of these factors is an important criterion for choosing the recharge areas.
Показать больше [+] Меньше [-]Occurrence, bioaccumulation and trophic dynamics of per- and polyfluoroalkyl substances in two tropical freshwater lakes | Occurrence, bioaccumulation and trophic dynamics of per- and polyfluoroalkyl substances in two tropical freshwater lakes Полный текст
2024
Adeogun, Aina O. | Chukwuka, Azubuike V. | Ibor, Oju Richard | Asimakopoulos, Alexandros | Zhang, Junjie | Arukwe, Augustine Ebeku
We have investigated the occurrence, distribution, and biomagnification of per- and polyfluoroalkyl substances (PFAS) in two tropical lakes (Asejire and Eleyele) of Southwestern Nigeria, with contrasting urban intensities. Over an 8-month period, we sampled sediment and fish species (Clarias gariepinus: CIG; Oreochromis niloticus: ON; Coptodon guineensis: CG; Sarotherodon melanotheron: SM) across trophic levels, and analyzed various PFAS congeners, in addition to a select group of toxicological responses. While herbivores (SM) and benthic omnivores (CIG) at Asejire exhibited elevated levels of PFBS and PFOS, the pelagic omnivores (ON) showed a dominance of PFOS, PFDA, PFHxDA and EtFOSE in the muscle. At the Eleyele urban lake, PFAS patterns was dominated by PFBS, EtFOSE, PFPeS, PFOcDA and PFOS in the herbivores (SM, CG), EtFOSE, PFOS and PFBS in the pelagic omnivore (ON) and benthic omnivore (ClG). The estimated biomagnification factor (BMF) analysis for both lakes indicated trophic level increase of PFOS, PFUnA and PFDA at the suburban lake, while PFOS and EtFOSE biomagnified at the urban lake. We detected the occurrence of diSAMPAP and 9CL-PF3ONS, novel compounds not commonly reported, in PFAS studies at both lakes. The studied toxicological responses varied across trophic groups in both lakes with probable modulations by environmental conditions, trophic structure, and relative PFAS exposures in the lakes. The present study documents, for the first time in Nigeria, or any other African country, the role of urbanization on contaminant load into the environment and their implications for contaminant dynamics within the ecosystem and for aquatic food safety. | publishedVersion
Показать больше [+] Меньше [-]Emerging and legacy contaminants in common minke whale from the Barents sea | Emerging and legacy contaminants in common minke whale from the Barents sea Полный текст
2023
Andvik, Clare Margaret | Haug, Tore | Lyche, Jan Ludvig | Borgå, Katrine
Persistent organic pollutants (POPs), including brominated flame retardants (BFRs), perfluoroalkyl substances (PFAS) and metals, can accumulate in marine mammals and be transferred to offspring. In this study, we analyzed 64 lipophilic POPs, including four emerging BFRs, in the blubber, liver and muscle of 17 adult common minke whales (Balaenoptera acutorostrata) from the Barents Sea to investigate occurrence and tissue partitioning. In addition, the placental transfer concentration ratios of 14 PFAS and 17 metals were quantified in the muscle of nine female-fetus pairs to investigate placental transfer. Legacy lipophilic POPs were the dominating compound group in every tissue, and we observed generally lower levels compared to previous studies from 1992 to 2001. We detected the emerging BFRs hexabromobenzene (HBB) and pentabromotoluene (PBT), but in low levels compared to the legacy POPs. We detected nine PFAS, and levels of perfluorooctane sulfonate (PFOS) were higher than detected from the same population in 2011, whilst levels of Hg were comparable to 2011. Levels of lipophilic contaminants were higher in blubber compared to muscle and liver on both a wet weight and lipid adjusted basis, but tissue partitioning of the emerging BFRs could not be determined due to the high number of samples below the limit of detection. The highest muscle ΣPFAS levels were quantified in fetuses (23 ± 8.7 ng/g ww), followed by adult males (7.2 ± 2.0 ng/gg ww) and adult females (4.5 ± 1.1 ng/g ww), showing substantial placental transfer from mother to fetus. In contrast, Hg levels in the fetus were lower than the mother. Levels were under thresholds for risk of health effects in the whales. This study is the first to report occurrence and placental transfer of emerging contaminants in common minke whales from the Barents Sea, contributing valuable new data on pollutant levels in Arctic wildlife. | publishedVersion
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