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Chemical composition of PM10 and its in vitro toxicological impacts on lung cells during the Middle Eastern Dust (MED) storms in Ahvaz, Iran
2016
Naimabadi, Abolfazl | Ghadiri, Ata | Idani, Esmaeil | Babaei, Ali Akbar | Alavi, Nadali | Shirmardi, Mohammad | Khodadadi, Ali | Marzouni, Mohammad Bagherian | Ankali, Kambiz Ahmadi | Rouhizadeh, Ahmad | Goudarzi, Gholamreza
Reports on the effects of PM10 from dust storm on lung cells are limited. The main purpose of this study was to investigate the chemical composition and in vitro toxicological impacts of PM10 suspensions, its water-soluble fraction, and the solvent-extractable organics extracted from Middle Eastern Dust storms on the human lung epithelial cell (A549). Samples of dust storms and normal days (PM10 < 200 μg m⁻³) were collected from December 2012 until June 2013 in Ahvaz, the capital of Khuzestan Province in Iran. The chemical composition and cytotoxicity were analyzed by ICP- OES and Lactase Dehydrogenase (LDH) reduction assay, respectively. The results showed that PM10 suspensions, their water-soluble fraction and solvent-extractable organics from both dust storm and normal days caused a decrease in the cell viability and an increase in LDH in supernatant in a dose–response manner. Although samples of normal days showed higher cytotoxicity than those of dust storm at the highest treated dosage, T Test showed no significant difference in cytotoxicity between normal days and dust event days (Pvalue > 0.05). These results led to the conclusions that dust storm PM10 as well as normal day PM10 could lead to cytotoxicity, and the organic compounds (PAHs) and the insoluble particle-core might be the main contributors to cytotoxicity. Our results showed that cytotoxicity and the risk of PM10 to human lung may be more severe during dust storm than normal days due to inhalation of a higher mass concentration of airborne particles. Further research on PM dangerous fractions and the most responsible components to make cytotoxicity in exposed cells is recommended.
Mostrar más [+] Menos [-]Influence of temperature on phenanthrene toxicity towards nitrifying bacteria in three soils with different properties
2016
Suszek-Łopatka, Beata | Maliszewska-Kordybach, Barbara | Klimkowicz-Pawlas, Agnieszka | Smreczak, Bożena
This study focused on the combined effect of environmental conditions (temperature) and contamination (polycyclic aromatic hydrocarbons, PAHs) on the activity of soil microorganisms (nitrifying bacteria). Phenanthrene (Phe) at five contamination levels (0, 1, 10, 100 and 1000 mg kg−1 dry mass of soil) was employed as a model PAH compound in laboratory experiments that were conducted at three temperatures (i.e., 20 °C (recommended by ISO 15685 method), 15 and 30 °C). Three soils with different properties were used in these studies, and the activity of the nitrifying bacteria was assessed based on nitrification potential (NP) determinations. For the statistical evaluation of the results, the ANCOVA (analysis of covariance) method for three independent variables (i.e., temperature, phenanthrene concentration, soil matrix (as a qualitative variable)) and their interactions was employed. The results indicated on the significant interaction of all studied factors. Temperature influenced the toxicity of Phe towards NP, and this effect was related to the Phe concentration as well as was varied for the different soils. A low content of soil organic matter (controlling bioavailability of phenanthrene to soil microorganisms) enhanced the combined effect of temperature and Phe toxicity, and a high biological activity of the soil (high NP values) increased the effect of high temperature on the Phe stimulatory influence. The results indicate that the temperature should not be neglected in tests evaluating PAH ecotoxicity, especially for reliable ecological risk assessment.
Mostrar más [+] Menos [-]Ten-year trends in urinary concentrations of triclosan and benzophenone-3 in the general U.S. population from 2003 to 2012
2016
Han, Changwoo | Lim, Youn-Hee | Hong, Yun-Chul
Despite their popular use and emerging evidences of adverse health effects, consequent trends in population level triclosan and benzophenone-3 exposure have been poorly evaluated. Therefore, we examined temporal trends of urinary triclosan and benzophenone-3 concentration in the general U.S. population by combining five cycles of National Health and Nutritional Examination Survey (NHANES, 2003–2012) data. We calculated percent changes and the least square geometric means (LSGMs) of urinary triclosan and benzophenone-3 concentration from 10,232 participants by using multivariable regression models. As a result, LSGM concentration of urinary triclosan and benzophenone-3 did not show statistically significant changes over the study period. [Percent change (95% CI): Triclosan, −7.35% (−20.86, 8.47); Benzophenone-3, 7.08% (−27.88, 58.99)] However, we found decreasing trend of urinary triclosan concentration and increasing trend of urinary benzophenone-3 concentration since 2005–2006. Socio-demographic factors which affected urinary concentration of triclosan and benzophenone-3 persisted throughout 10 year study period. Highest income group showed higher level of urinary triclosan and benzophenone-3 concentration. Overall concentration of benzophenone-3 was higher in female than in male, and higher in non-Hispanic Whites than any other races/ethnicities.
Mostrar más [+] Menos [-]Weathering steel as a potential source for metal contamination: Metal dissolution during 3-year of field exposure in a urban coastal site
2016
Raffo, Simona | Vassura, Ivano | Chiavari, Cristina | Martini, Carla | Bignozzi, Maria C. | Passarini, Fabrizio | Bernardi, Elena
Surface and building runoff can significantly contribute to the total metal loading in urban runoff waters, with potential adverse effects on the receiving ecosystems. The present paper analyses the corrosion-induced metal dissolution (Fe, Mn, Cr, Ni, Cu) from weathering steel (Cor-Ten A) with or without artificial patinas, exposed for 3 years in unsheltered conditions at a marine urban site (Rimini, Italy). The influence of environmental parameters, atmospheric pollutants and surface finish on the release of dissolved metals in rain was evaluated, also by means of multivariate analysis (two-way and three-way Principal Component Analysis). In addition, surface and cross-section investigations were performed so as to monitor the patina evolution. The contribution provided by weathering steel runoff to the dissolved Fe, Mn and Ni loading at local level is not negligible and pre-patination treatments seem to worsen the performance of weathering steel in term of metal release. Metal dissolution is strongly affected by extreme events and shows seasonal variations, with different influence of seasonal parameters on the behaviour of bare or artificially patinated steel, suggesting that climate changes could significantly influence metal release from this alloy. Therefore, it is essential to perform a long-term monitoring of the performance, the durability and the environmental impact of weathering steel.
Mostrar más [+] Menos [-]Is particulate air pollution at the front door a good proxy of residential exposure?
2016
Zauli Sajani, Stefano | Trentini, Arianna | Rovelli, Sabrina | Ricciardelli, Isabella | Marchesi, Stefano | Maccone, Claudio | Bacco, Dimitri | Ferrari, Silvia | Scotto, Fabiana | Zigola, Claudia | Cattaneo, Andrea | Cavallo, Domenico Maria | Lauriola, Paolo | Poluzzi, Vanes | Harrison, Roy M.
The most advanced epidemiological studies on health effects of air pollution assign exposure to individuals based on residential outdoor concentrations of air pollutants measured or estimated at the front-door. In order to assess to what extent this approach could cause misclassification, indoor measurements were carried out in unoccupied rooms at the front and back of a building which fronted onto a major urban road. Simultaneous measurements were also carried out at adjacent outdoor locations to the front and rear of the building. Two 15-day monitoring campaigns were conducted in the period June–December 2013 in a building located in the urban area of Bologna, Italy. Particulate matter metrics including PM2.5 mass and chemical composition, particle number concentration and size distribution were measured. Both outdoor and indoor concentrations at the front of the building substantially exceeded those at the rear. The highest front/back ratio was found for ultrafine particles with outdoor concentration at the front door 3.4 times higher than at the rear. A weak influence on front/back ratios was found for wind direction. Particle size distribution showed a substantial loss of particles within the sub-50 nm size range between the front and rear of the building and a further loss of this size range in the indoor data. The chemical speciation data showed relevant reductions for most constituents between the front and the rear, especially for traffic related elements such as Elemental Carbon, Iron, Manganese and Tin. The main conclusion of the study is that gradients in concentrations between the front and rear, both outside and inside the building, are relevant and comparable to those measured between buildings located in high and low traffic areas. These findings show high potential for misclassification in the epidemiological studies that assign exposure based on particle concentrations estimated or measured at subjects’ home addresses.
Mostrar más [+] Menos [-]The effect of drinking water salinity on blood pressure in young adults of coastal Bangladesh
2016
Talukder, Mohammad Radwanur Rahman | Rutherford, Shannon | Phùng, Dũng | Islam, Mohammad Zahirul | Chu, Cordia
More than 35 million people in coastal Bangladesh are vulnerable to increasing freshwater salinization. This will continue to affect more people and to a greater extent as climate change projections are realised in this area in the future. However the evidence for health effects of consuming high salinity water is limited. This research examined the association between drinking water salinity and blood pressure in young adults in coastal Bangladesh. We conducted a cross-sectional study during May-June 2014 in a rural coastal sub-district of Bangladesh. Data on blood pressure (BP) and salinity of potable water sources was collected from 253 participants aged 19–25 years. A linear regression method was used to examine the association between water salinity exposure categories and systolic BP (SBP) and diastolic BP (DBP) level. Sixty five percent of the study population were exposed to highly saline drinking water above the Bangladesh standard (600 mg/L and above). Multivariable linear regression analyses identified that compared to the low water salinity exposure category (<600 mg/L), those in the high water salinity category (>600 mg/L), had statistically significantly higher SBP (B 3.46, 95% CI 0.75, 6.17; p = 0.01) and DBP (B 2.77, 95% CI 0.31, 5.24; p = 0.03). Our research shows that elevated salinity in drinking water is associated with higher BP in young coastal populations. Blood pressure is an important risk factor of hypertension and cardiovascular diseases. Given the extent of salinization of freshwater in many low-lying countries including in Bangladesh, and the likely exacerbation related to climate change-induced sea level rise, implementation of preventative strategies through dietary interventions along with promotion of low saline drinking water must be a priority in these settings.
Mostrar más [+] Menos [-]Resuspension of sediment, a new approach for remediation of contaminated sediment
2016
Pourabadehei, Mehdi | Mulligan, Catherine N.
Natural events and anthropogenic activities are the reasons of undesirable resuspension of contaminated sediments in aquatic environment. Uncontrolled resuspension could remobilize weakly bound heavy metals into overlying water and pose a potential risk to aquatic ecosystem. Shallow harbours, with contaminated sediments are subjected to the risk of uncontrolled resuspension. Remediation of sediments in these areas cannot be performed by conventional in situ methods (e.g. capping with or without reactive amendment). Ex situ remediation also requires dredging of sediment, which could increase the risk of spreading contaminants. Alternatively, the resuspension technique was introduced to address these issues. The concept of the resuspension method is that finer sediments have a greater tendency to adsorb the contamination. Therefore, finer sediments, believed carry more concentration of contaminants, were targeted for removal from aquatic environment by a suspension mechanism in a confined water column. The objective of this study was to evaluate the feasibility of the resuspension technique as a new approach for remediation of contaminated sediment and a viable option to reduce the risk of remobilization of contaminants in harbours due to an undesirable resuspension event. Unlike the common in situ techniques, the resuspension method could successfully reduce the total concentration of contaminants in almost all samples below the probable effect level (PEL) with no significant change in the quality of overlying water. The results indicated that removal efficiency could be drastically enhanced for metals in sediment with a higher enrichment factor. Moreover, availability of metals (e.g. Cd and Pb) with a high concentration in labile fractions was higher in finer sediments with a high enrichment factor. Consequently, removal of contaminants from sediment through the resuspension method could reduce the risk of mobility and availability of metals under changing environmental conditions. Potential dredging in harbours could be performed safer and more cost-effective afterward.
Mostrar más [+] Menos [-]Modelling and mapping trace element accumulation in Sphagnum peatlands at the European scale using a geomatic model of pollutant emissions dispersion
2016
Diaz-de-Quijano, Maria | Joly, Daniel | Gilbert, Daniel | Toussaint, Marie-Laure | Franchi, Marielle | Fallot, Jean-Michel | Bernard, Nadine
Trace elements (TEs) transported by atmospheric fluxes can negatively impact isolated ecosystems. Modelling based on moss-borne TE accumulation makes tracking TE deposition in remote areas without monitoring stations possible. Using a single moss species from ombrotrophic hummock peatlands reinforces estimate quality. This study used a validated geomatic model of particulate matter dispersion to identify the origin of Cd, Zn, Pb and Cu accumulated in Sphagnum capillifolium and the distance transported from their emission sources. The residential and industrial sectors of particulate matter emissions showed the highest correlations with the TEs accumulated in S. capillifolium (0.28(Zn)-0.56(Cu)) and (0.27(Zn)-0.47(Cu), respectively). Distances of dispersion varied depending on the sector of emissions and the considered TE. The greatest transportation distances for mean emissions values were found in the industrial (10.6 km when correlating with all TEs) and roads sectors (13 km when correlating with Pb). The residential sector showed the shortest distances (3.6 km when correlating with Cu, Cd, and Zn). The model presented here is a new tool for evaluating the efficacy of air pollution abatement policies in non-monitored areas and provides high-resolution (200 × 200 m) maps of TE accumulation that make it possible to survey the potential impacts of TEs on isolated ecosystems.
Mostrar más [+] Menos [-]Occurrence of Dechlorane compounds and polybrominated diphenyl ethers (PBDEs) in the Korean general population
2016
Kim, Jongchul | Son, Min-hui | Shin, Eun-su | Choi, Sung-Deuk | Chang, Yoon Seok
Dechlorane compounds, including Dechlorane Plus (DP), mirex, and Dechlorane (Dec) 602, 603 and 604, were measured in 61 serum samples collected from a Korean urban area (Seoul) in 2013. Dechlorane Plus and Dec 602 were dominant in most samples, whereas Dec 604 was not detected in any samples. The median value of DP was 0.75 ng/g lipid, which was comparable with the levels observed in Europe and Canada, but lower than that observed in China. Statistically significant correlations among Dechlorane compounds were observed. The median anti-isomer fractional abundance (fanti) was 0.74, and a negative correlation between fanti and the DP concentration in serum samples was observed. Polybrominated diphenyl ethers (PBDEs) were also measured for comparison with Dechlorane compounds, and BDE-153 was found the most abundant congener with a median value of 1.43 ng/g lipid. A time trend of Dechlorane compounds was investigated in 7 pooled serum samples to cover the period from 2006 to 2013. A distinct trend of Dechlorane compounds was not observed, while PBDEs steadily decreased with time.
Mostrar más [+] Menos [-]Current status and historical variations of DDT-related contaminants in the sediments of Lake Chaohu in China and their influencing factors
2016
Kang, Lei | He, Qi-Shuang | He, Wei | Kong, Xiang-Zhen | Liu, Wen-Xiu | Wu, Wen-Jing | Li, Yi-Long | Lan, Xin-Yu | Xu, Fu-Liu
The temporal-spatial distributions of DDT-related contaminants (DDXs), including DDT (dichlorodiphenyltrichloroethane), DDE (dichlorodiphenyldichloroethylene) and DDD (dichlorodiphenyldichloroethane), in the sediments of Lake Chaohu and their influencing factors were studied. p,p-DDE and p,p-DDD were found to be the two dominant components of DDXs in both surface and core sediments. The parent DDT compounds were still detectable in sediment cores after the late 1930s. Historical usage of technical DDT was identified as the primary source of DDXs in sediments, as indicated by DDT/(DDD + DDE) ratios of less than one. The residual levels of DDXs were higher in the surface and core sediments in the western lake area than in other lake areas, which might be due to the combined inflow effects of municipal sewage, industrial wastewater and agricultural runoff. The DDX residues in the sediment cores reached peak values in the late 1970s or early 1980s. There were significant positive relationships between DDX residues in sediment cores with annual DDT production and with fine particulate sizes (<4.5 μm). The relationship between the DDXs and TOC in sediment was complex, as indicated by the significant differences among the surface and core sediments. The algae-derived organic matter significantly influenced the amount of residue, composition and distribution of DDXs in the sediments. The DDD/DDE ratios responded well to the anaerobic conditions in the sediments that were caused by algal blooms after the late 1970s in the western lake area. This suggests that the algae-derived organic matter was an important factor and served as a biomarker of eutrophication and also affected the DDX residues and lifecycle in the lake ecosystem.
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