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Blood cadmium burden and the risk of nasopharyngeal carcinoma: a case–control study in Chinese Chaoshan population Texte intégral
2015
Peng, Lin | Wang, Xiaoling | Huo, Xia | Xu, Xijin | Lin, Kun | Zhang, Jingwen | Huang, Yue | Wu, Kusheng
Cadmium is a ubiquitous carcinogenic pollutant with multiple biological effects. Both observational and experimental studies have suggested associations between cadmium and the rates of many types of cancers. The aim of the present study was to evaluate whether cadmium exposure is associated with nasopharyngeal carcinoma (NPC) in a population with a relatively high prevalence in southeast China. Hospital-based 134 NPC cases and 132 cancer-free controls were recruited from a cancer hospital in Chaoshan area, southeast of China. Basic clinical data and information of lifetime styles, smoking, and drinking as well as other demographic characteristics were also collected from medical records. Blood cadmium levels (BCLs) were detected by graphite-furnace atomizer absorption spectrophotometer (GFAAS). BCLs and over-limit ratios between cases and controls were compared. The relationships between BCLs and NPC were explored by comparing BCLs differences between/among different characteristics of related factors and logistic regression analysis. In addition, BCLs within cases were also compared in relation to the disease clinical stages, pathological types, and metastasis. The median concentration of blood cadmium in cases (3.84, interquartile range 2.21–6.10) was significantly higher than that of controls (2.28, interquartile range 1.79–3.45). The over-limit ratio (≥5 μg/L) in cases was also higher than that in controls (35.1 vs. 13.6 %, χ ² = 16.55, p < 0.001). Smokers tended to have high levels of cadmium burden, and smokers with longer smoking pack-years in cases had relatively higher BCLs (p = 0.001). NPC patients with diseases history presented lower cadmium burden (p = 0.020). In the NPC cases, BCLs were positively associated with clinical stages and N classification (r = 0.193, 0.187, respectively, p < 0.05). Cadmium seems to be a risk factor of NPC, and high cadmium exposure may promote the occurrence and development of NPC.
Afficher plus [+] Moins [-]Heavy metals in normal mucosa and nasal polyp tissues from Tunisian patients Texte intégral
2015
Khlifi, Rim | Olmedo, Pablo | Gil, Fernando | Chakroun, Amine | Hammami, Boutheina | Hamza-Chaffai, Amel
Despite growing evidence that bacteria, fungi, allergens, and superantigens play a prominent role in the pathophysiology of nasal polyps (NP), the exact cause of polyposis is still unknown. The etiology of NP is considered multifactorial. Until now, there is no information on the presence of heavy metals, such as cadmium (Cd), chromium (Cr), nickel (Ni), and arsenic (As) or of their role, in the pathogenesis of NP disease. In this study, concentrations of these four metals in tissue of NP were determined using Atomic Absorption Spectrometry. The Ni, Cr, and As levels in NP tissues were 2.1-, 3.2-, and 8.0-fold higher than those of normal mucosa (p < 0.05), respectively. A strong effect of cumulative smoking as expressed in the number of pack per year (PY), Ni, As, and Cd levels in NP tissue samples of patients ever-smokers (1–20 and >20 PY) are significantly higher than those of non-smokers (p = 0.006, 0.002, and < 0.001, respectively). The highest As concentrations among patients lived at polluted areas (1–25 and > 25 years) were observed in both nasal mucosa and NP tissues. The Ni and As in both nasal mucosa and NP tissues of patients occupationally exposed were significantly higher than non-exposed group. Cr and As levels were found to be associated with NP stage classification (p < 0.05). This is the first report to describe an association between concentrations of metals (Cr, As, and Ni) in human NP tissues and the risk of NP disease. Tissue metal levels have increased due to smoking, environmental, and occupational exposure. Therefore, heavy metal exposure may increase the risk of NP in the Tunisian population. The considerable risk in the category of highest cumulative exposure argues for an association between heavy metals exposure and nasal polyposis risk. Future investigations with larger samples should better elucidate this association.
Afficher plus [+] Moins [-]Variation in tolerance to common marine pollutants among different populations in two species of the marine copepod Tigriopus Texte intégral
2015
Sun, Patrick Y. | Foley, Helen B. | Bao, Vivien W. W. | Leung, Kenneth M. Y. | Edmands, Suzanne
Geographical variation in chemical tolerance within a species can significantly influence results of whole animal bioassays, yet a literature survey showed that the majority of articles using bioassays did not provide detail on the original field collection site of their test specimens confounding the ability for accurate replication and comparison of results. Biological variation as a result of population-specific tolerance, if not addressed, can be misinterpreted as experimental error. Our studies of two marine copepod species, Tigriopus japonicus and Tigriopus californicus, found significant intra- and inter-specific variation in tolerance to copper and tributyltin. Because both species tolerate copper concentrations orders of magnitude higher than those found in coastal waters, difference in copper tolerance may be a by-product of adaptation to other stressors such as high temperature. Controlling for inter-population tolerance variation will greatly strengthen the application of bioassays in chemical toxicity tests.
Afficher plus [+] Moins [-]Changes in the abundance of sugars and sugar-like compounds in tall fescue (Festuca arundinacea) due to growth in naphthalene-treated sand Texte intégral
2015
Balasubramaniyam, Anuluxshy | Harvey, Patricia J
The hydrophilic metabolome of tall fescue (Festuca arundinacea) adapted to grow in naphthalene-treated sand (0.8 g kg⁻¹sand dw) was analysed using gas chromatography-mass spectrometry, and peaks corresponding to the more abundant compounds were tentatively identified from analysis of their mass spectral features and reference to the NIST Mass Spectral Database. Particular attention was paid to sugars as they are known to play important roles as stress regulators in plants. The results showed that the abundance of sugars was greater in the roots but lesser in the shoots of treated plants when compared to their control counterparts. The results for indole acetic acid (IAA) were notable: IAA was prominently less in the treated roots compared to shoots, and in treated shoots, IAA was particularly subdued compared to untreated shoots consistent with IAA degradation in treated plant tissues. The differences in the molecular phenotype between control and treated plants were expressed in root structural differences. The treated roots were modified to have greater suberisation, enhanced thickening in the endodermis and distortions in the cortical zone as demonstrated through scanning electron and epi-fluorescence microscopy.
Afficher plus [+] Moins [-]Neighborhood epidemiological monitoring and adult mental health: European Quality of Life Survey, 2007–2012 Texte intégral
2015
Shiue, Ivy
Little is monitored on perceived neighborhood noise, quality of drinking water, air quality, rubbish, traffic, etc. at a continental scale. This study was aimed to examine the relationships of such neighborhood risks and mental health in adults and the very old in an international and population-based setting across Europe. Data were retrieved from the European Quality of Life Survey, 2007–2012 including demographics, living conditions, income and financial situation, housing and local environment, family, work, health, social participation and quality of social services. Adults aged 18 and above were included for statistical analysis (n = 79,270). Analysis included chi-square test, t test and logistic regression modeling. People who lived in town or city tended to indicate certain major problems for them such as noise (odds ratio (OR) 2.34, 95 % confidence interval (CI) 2.17–2.53, P < 0.001), air quality (OR 2.76, 95 % CI 2.54–3.00, P < 0.001), low quality of drinking water (OR 1.33, 95 % CI 1.23–1.43, P < 0.001), crime and/or violence (OR 2.92, 95 % CI 2.68–3.19, P < 0.001), rubbish (OR 3.68, 95 % CI 3.41–3.97, P < 0.001) and traffic congestion (OR 2.64, 95 % CI 2.45–2.85, P < 0.001). People who reported major problems on noise (OR 2.19, 95 % CI 1.96–2.45, P < 0.001), air quality (OR 2.11, 95 % CI 1.87–2.37, P < 0.001), low quality of drinking water (OR 2.40, 95 % CI 2.14–2.68, P < 0.001), crime and/or violence (OR 2.13, 95 % CI 1.88–2.41, P < 0.001), rubbish (OR 1.98, 95 % CI 1.77–2.11, P < 0.001) and traffic congestion (OR 1.50, 95 % CI 1.34–1.68, P < 0.001) were also classified as having depression. Perceived neighborhood conditions were associated with adult mental health across Europe. Future neighborhood monitoring research moving from the etiological to neighborhood management would be suggested.
Afficher plus [+] Moins [-]Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour Texte intégral
2015
Claveau, Julie | Monperrus, Mathilde | Jarry, Marc | Pinaly, Herve | Baudrimont, Magalie | Gonzalez, Patrice | Amouroux, David | Bardonnet, Agnès | Bolliet, Valérie
Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour Texte intégral
2015
Claveau, Julie | Monperrus, Mathilde | Jarry, Marc | Pinaly, Herve | Baudrimont, Magalie | Gonzalez, Patrice | Amouroux, David | Bardonnet, Agnès | Bolliet, Valérie
Overall recruitment of European glass eels (Anguilla anguilla) has decreased significantly since the early 1980s. Due to their long life cycle, benthic/demersal habits and high lipid content, eels might accumulate high concentrations of contaminants, but data concerning glass eels are still scarce. This study provides original data on methylmercury (MeHg) concentrations in glass eels at spatial (marine and estuarine), annual and seasonal scales. The relationship between MeHg concentrations in glass eels and their propensity to migrate up estuaries was also investigated. MeHg data were individually related to the eels’ energetic condition which was estimated by dry weight. Glass eel migratory behaviour was investigated in an experimental flume and related to the MeHg concentration and dry weight at the individual scale. Marine and estuarine glass eels were caught from 2004 to 2011. There was a strong inverse correlation between MeHg concentrations and dry weight. MeHg concentrations increased in marine and estuarine glass eels from 2004 to 2009 and from 2004 to 2010, respectively, and then, both groups decreased in 2011. On a seasonal time scale, MeHg concentrations were higher at the end of the fishing season (April). MeHg bioaccumulation is likely to result from different sources, but the lack of significant differences between marine and estuarine glass eels suggests that direct contamination during estuarine migration is low. Other sources such as maternal transfer or oceanic contamination are discussed.
Afficher plus [+] Moins [-]Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour Texte intégral
2015
Claveau, Julie | Monperrus, Mathilde | Amouroux, David | Jarry, Marc | Pinaly, Hervé | Baudrimont, Magalie | Gonzalez, Patrice | Bardonnet, Agnes | Bolliet, Valérie | Ecologie Comportementale et Biologie des Populations de Poissons (ECOBIOP) ; Institut National de la Recherche Agronomique (INRA)-Université de Pau et des Pays de l'Adour (UPPA) | Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM) ; Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | J.C. ’ s PhD thesis was funded by the University of Pau et les Pays de l ’ Adour (ED 211). The project was partly supported by funding from the Office National de l ’ Eau and Milieux Aquatiques (ONEMA), from the European Union within the framework of the ORQUE SUDOE project, the Conseil Général des Pyrénées Atlantiques within the framework of the EXPLOR project and by the University of Pau (BQR MIRA)
International audience | Overall recruitment of European glass eels (Anguilla anguilla) has decreased significantly since the early 1980s. Due to their long life cycle, benthic/demersal habits and high lipid content, eels might accumulate high concentrations of contaminants, but data concerning glass eels are still scarce. This study provides original data on methylmercury (MeHg) concentrations in glass eels at spatial (marine and estuarine), annual and seasonal scales. The relationship between MeHg concentrations in glass eels and their propensity to migrate up estuaries was also investigated. MeHg data were individually related to the eels’ energetic condition which was estimated by dry weight. Glass eel migratory behaviour was investigated in an experimental flume and related to the MeHg concentration and dry weight at the individual scale. Marine and estuarine glass eels were caught from 2004 to 2011. There was a strong inverse correlation between MeHg concentrations and dry weight. MeHg concentrations increased in marine and estuarine glass eels from 2004 to 2009 and from 2004 to 2010, respectively, and then, both groups decreased in 2011. On a seasonal time scale, MeHg concentrations were higher at the end of the fishing season (April). MeHg bioaccumulation is likely to result from different sources, but the lack of significant differences between marine and estuarine glass eels suggests that direct contamination during estuarine migration is low. Other sources such as maternal transfer or oceanic contamination are discussed
Afficher plus [+] Moins [-]Distinguishing anthropogenic and natural sources of trace elements in soils undergoing recent 10-year rapid urbanization: a case of Donggang, Eastern China Texte intégral
2015
Lv, Jianshu | Liu, Yang | Zhang, Zulu | Zhou, Rujia | Zhu, Yuchi
A total of 59 samples consisting of 45 topsoils samples and 14 subsoils samples were collected from urban soils of Donggang and were analyzed for soil properties and 12 trace elements. The mean contents of As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Se, V, and Zn in topsoils were 5.76, 0.20, 9.88, 44.82, 17.69, 0.05, 578.96, 19.98, 28.38, 0.21, 58.88, and 58.32 mg kg⁻¹, respectively. The mean enrichment factor results suggested that Hg, Cd, Pb, Cu, Se, and Zn were enriched in topsoils compared with subsoils. Spatial distribution maps of trace elements indicated that Hg, Cd, Pb, Cu, Se, and Zn had similar patterns, with the highest values in the industrial region. There were no significant associations displayed between spatial distributions of As, Co, Cr, Mn, Ni, and V and the industrial region. Through correlation analysis, stepwise regression analysis, and redundancy analysis, three main sources of 12 trace elements were identified. Cd, Hg, and Se originated from industrial emissions and coal combustion, and As, Co, Cr, Mn, Ni, and V had a lithogenic origin. The combination of human activities and natural sources contributed to the contents of Cu, Pb, and Zn, and the human activities included industrial and traffic emissions.
Afficher plus [+] Moins [-]Competitive sorption and desorption of trace elements by Tunisian Aridisols Calcorthids Texte intégral
2015
Sahraoui, Hamdi | Andrade, María Luisa | Hachicha, Mohamed | Vega, Flora Alonso
The sorption and retention processes play an important role in determining the bioavaibility and fate of trace elements in soils. Sorption and desorption of Pb²⁺, Zn²⁺, Ni²⁺, Cu²⁺, and Co²⁺ in three Tunisian Aridisols Calcorthids (AR1, AR2, and AR3) were studied using batch experiments. Sorption and retention capacities were determined by means of K ᵣ parameter and they were related to soil properties. The results showed that in all studied soils, K ᵣ values for Pb²⁺ and Cu²⁺ were higher than those of Zn²⁺, Ni²⁺, and Co²⁺ indicating that soils have higher affinity for the first ones. The high sorption and retention capacity of the three studied soils is ascribed to their alkaline pH and their high carbonates contents favoring the precipitation of these elements. Moreover, bivariate correlation analysis showed that sorption and retention of the studied cations was also strongly correlated with clay fraction and Fe oxides contents. All soils show high sorption irreversibility of Pb²⁺, Zn²⁺, Ni²⁺, Cu²⁺, and Co²⁺. The soils with highest sorption capacity show also the highest irreversibility.
Afficher plus [+] Moins [-]Air quality modeling in the Oviedo urban area (NW Spain) by using multivariate adaptive regression splines Texte intégral
2015
Nieto, P. J García | Antón, J. C Álvarez | Vilán, J. A Vilán | García-Gonzalo, E.
The aim of this research work is to build a regression model of air quality by using the multivariate adaptive regression splines (MARS) technique in the Oviedo urban area (northern Spain) at a local scale. To accomplish the objective of this study, the experimental data set made up of nitrogen oxides (NO ₓ), carbon monoxide (CO), sulfur dioxide (SO₂), ozone (O₃), and dust (PM₁₀) was collected over 3 years (2006–2008). The US National Ambient Air Quality Standards (NAAQS) establishes the limit values of the main pollutants in the atmosphere in order to ensure the health of healthy people. Firstly, this MARS regression model captures the main perception of statistical learning theory in order to obtain a good prediction of the dependence among the main pollutants in the Oviedo urban area. Secondly, the main advantages of MARS are its capacity to produce simple, easy-to-interpret models, its ability to estimate the contributions of the input variables, and its computational efficiency. Finally, on the basis of these numerical calculations, using the MARS technique, conclusions of this research work are exposed.
Afficher plus [+] Moins [-]Formaldehyde exposure in gross anatomy laboratory of Suranaree University of Technology: a comparison of area and personal sampling Texte intégral
2015
Saowakon, Naruwan | Ngernsoungnern, Piyada | Watcharavitoon, Pornpun | Ngernsoungnern, Apichart | Kosanlavit, Rachain
Cadavers are usually preserved by embalming solution which is composed of formaldehyde (FA), phenol, and glycerol. Therefore, medical students and instructors have a higher risk of exposure to FA inhalation from cadavers during dissection. Therefore, the objective of this study was to evaluate the FA exposure in indoor air and breathing zone of medical students and instructors during dissection classes in order to investigate the relationship between them. The indoor air and personal air samples in breathing zone were collected three times during anatomy dissection classes (in January, August, and October of 2014) with sorbent tubes, which were analyzed by high-performance liquid chromatography (HPLC). The air cleaner machines were determined by weight measurement. Pulmonary function tests and irritation effects were also investigated. The mean of FA concentrations ranged from 0.117 to 0.415 ppm in the indoor air and from 0.126 to 1.176 ppm in the breathing zone of students and instructors. All the personal exposure data obtained exceeded the threshold limit of NIOSH and WHO agencies. The air cleaner machines were not significant difference. The pulmonary function of instructors showed a decrease during attention of classes and statistically significant decreasing in the instructors more than those of the students. Clinical symptoms that were observed in nose and eyes were irritations with general fatigue. We suggested that the modified exhaust ventilation and a locally ventilated dissection work table were considered for reducing FA levels in the gross anatomy dissection room.
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