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Occurrence of persistent organic pollutants in air at different sites in the province of Córdoba, Argentina
2019
Pegoraro, Cesar N. | Wannaz, Eduardo D.
The occurrence of persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) in the atmosphere of six sites with different emission sources in the province of Córdoba, Argentina, was analyzed. The sites included urban, industrial, agricultural, and mountain areas. Samples were collected using passive air samplers (PAS) consisting of polyurethane foam disks (PUF). Samples were analyzed for 12 PAHs, 31 polychlorinated biphenyls (PCBs), 12 organochlorine pesticides (OCPs), and 11 polybrominated diphenyl ethers (PBDEs). The concentrations of PAHs in the atmosphere were elevated at urban sites and were even higher at the industrial site. With respect to OCPs, it was observed that the concentrations of endosulfan were greater at the agricultural site (AGR) (416 ± 4 pg m⁻³). For hexachlorocyclohexanes (HCHs), only the alpha isomer was detected and there were minimal differences between the different sampling sites (5.9–13.3 pg m⁻³). In the case of dieldrin, the highest concentrations (33.6 pg m⁻³) were found at the mountain site, which may have been due to its use for insect control. Although heptachlor epoxide was not detected, the concentration of heptachlor was significantly higher at the agricultural and downtown sites (∼ 3.6 pg m⁻³). Regarding DDTs, the isomers p,p′-DDT and p,p′-DDE showed the highest concentrations at the mountain site (ΣDDT 120 ± 12 pg m⁻³) and downtown site (ΣDDT 157 ± 62 pg m⁻³). The relationship between the isomers suggested that at the downtown site, the contribution of this pesticide to the environment was recent, probably for the control of diseases vectors. The congener pattern of PBDEs was dominated by BDE-47, and BDE-99 at all sites, with the downtown site having the highest concentrations of compound esters (ΣPBDEs 118 ± 38 pg m⁻³). Finally, high concentrations of PCBs were found at the industrial site (ΣPCBs 1677 ± 134 pg m⁻³), and the predominating homologs were 5-Cl and 6-Cl, in contrast to the other sites where PCBs were dominated by 3-Cl and 4-Cl. This is the first study of POPs carried out in the province of Córdoba.
Afficher plus [+] Moins [-]Heavy metal pollution in Nanchang City and its health implication on traffic policemen
2019
Liu, Xiaozhen | Liang, Yue | Guo, Jiangmei
The purpose of this study is to evaluate the health effect of heavy metal pollution in air pollutants on traffic policemen. This study will facilitate the scientific evaluation of health status of traffic policemen. PM₁₀ samples were collected from industrial area, congested traffic area and residential area respectively in Nanchang City, and the concentrations of heavy metals were analyzed. The traffic policemen were examined through chest X-rays. The total of 637 urine samples and 142 blood samples have been collected, and the concentrations of Pb in samples were detected. Vehicle flux data of Nanchang City were collected from the Department of Transport’s Traffic Management. Statistic analyses were carried out by statistics software of Excel 2003 and SPSS20.0, and the health effect of heavy metal pollution of PM₁₀ on the traffic policemen was evaluated. The discharge of pollutants from enterprises is an important reason for the high content of heavy metals in urban air pollution. With the rapid growth of urban traffic flow, Bayi Bridge becomes an important transportation hinge in Nanchang City, and the bidirectional traffic flow rate through the bridge at peak hours reached 99 vehicles per minute. The latent hazard of occupational harm on the traffic policemen caused by automobile exhaust is increasing. The concentration of Pb in the urine and blood samples from traffic policemen working in Nanchang City was 268.310 ± 177.031 and 22.873 ± 21.137 μg/L, respectively. Both results (2.04% of Pb in urine and 18.31% of Pb in blood) exceeded the highest limit of observed occupationally outdoor workers. This study provides an initial contribution for the assessment of city air pollution, esp. the health effect of heavy metal (Pb) pollution on traffic policemen.
Afficher plus [+] Moins [-]The possible global hazard of cell phone radiation on thyroid cells and hormones: a systematic review of evidences
2019
Asl, Jafar Fatahi | Larijani, Bagher | Zakerkish, Mehrnoosh | Rahim, Fakher | Shirbandi, Kiarash | Akbari, Rasoul
The aim of this review was to investigate the effects of possible harmful waves from either cell phone use or being within the range of the cell phone from 450 to 3800 MHz on the thyroid cells and hormones. Eight electronic datasets were systematically searched using MeSH terms, including “cell phone,” “mobile phone,” “GSM,” “radio frequency,” “smartphone,” “triiodothyronine,” “thyroxin,” “thyroid-stimulating hormone,” “T3,” “T4,” “TSH,” and “morphological” and all possible combinations, to identify relevant studies published up to Dec 2018. We also manually searched the reference lists of potentially selected studies to identify further relevant publications. About 161 relevant studies were initially found. After screening titles and abstracts, 139 studies were excluded, and finally 22 studies (comprising 7182 cases) were included in the qualitative synthesis. Of the 22 included studies, 11 studies reported changes in T3 and T4 levels (six reported a decrease in T3 levels and one reported increase in it); moreover, five found decreased T4 levels and two studies an increased level. In other 10 studies, TSH alteration was reported. Of these, two studies reported a decrease in TSH level and one reported an increase in the hormone levels, while in the remaining studies non-significant changes were reported. Finally, seven studies examined histological changes in the thyroid gland follicles and showed that the volume of these cells was reduced. Based on the evidence discussed above, the reduction in diameter of thyroid follicles is potentially linked with cell phone radiation. Exposure may negatively influence the iodine uptake in the thyroid gland or increases temperature effect on the thyroid gland. However, further research are needed in order to show that the level of TSH and thyroid hormone suppression by microwave.
Afficher plus [+] Moins [-]Does globalization increase the ecological footprint? Empirical evidence from Malaysia
2019
Ahmed, Zahoor | Wang, Zhaohua | Mahmood, Faisal | Hafeez, Muhammad | Ali, Nazakat
This study focuses to investigate the relationship between globalization and the ecological footprint for Malaysia from 1971 to 2014. The results of the Bayer and Hanck cointegration test and the ARDL bound test show the existence of cointegration among variables. The findings disclose that globalization is not a significant determinant of the ecological footprint; however, it significantly increases the ecological carbon footprint. Energy consumption and economic growth stimulate the ecological footprint and carbon footprint in Malaysia. Population density reduces the ecological footprint and carbon footprint. Further, financial development mitigates the ecological footprint. The causality results disclose the feedback hypothesis between energy consumption and economic growth in the long run and short run.
Afficher plus [+] Moins [-]Trace elements in Plantago lanceolata L., a plant used for herbal and food preparations: new data and literature review
2019
Drava, Giuliana | Cornara, Laura | Giordani, Paolo | Minganti, Vincenzo
Plantago lanceolata L. is a common grassland and roadside plant, widely used in many countries in food and herbal preparations. In this study, samples of this wild plant were collected from rural, suburban/urban, and industrial environments; the concentrations of As, Cd, Co, Cu, Fe, Mn, Ni, P, Pb, V, and Zn were measured in the edible parts of the plant (leaves), in the roots, and in the soils in order to calculate the bioaccumulation and translocation factors. The data obtained were compared with literature data available. Except for samples collected near mines and smelting plants, where Cd, Pb, and Zn concentrations were up to 15 times higher, in all other cases, no differences were observed with respect to samples from rural areas, except for Pb concentration, which was 3 times higher in urban areas. In the samples collected in our study area, the metal content does not pose particular health risks; however, even within a quite restricted region like the investigated area, high metal concentrations, possibly due to the presence of particular substrates, were observed in some samples collected from areas considered “clean” and suitable for wild food plant gathering.
Afficher plus [+] Moins [-]Outdoor air pollution pregnancy exposures are associated with behavioral problems in China’s preschoolers
2019
Ren, Yunzhao | Yao, Xing | Liu, Yisi | Liu, Suyang | Li, Xiao | Huang, Qing | Liu, Feifei | Li, Na | Lu, Yuanan | Yuan, Zhanpeng | Li, Shiyue | Xiang, Hao
There are mounting evidences indicated that maternal exposure to outdoor air pollutants in pregnancy affects children’s neural development, but the researches on children’s behavioral difficulties are seldom. We explored the association between maternal exposure to outdoor air pollution during different trimesters of pregnancy and the prevalence of behavioral difficulties among 657 preschool children aged 3–4 from three kindergartens in Wuhan, China. This is a cross-sectional study. Children’s behavioral difficulties were assessed by the Strengths and Difficulties Questionnaire (SDQ) (reported by parents). Maternal exposure to outdoor air pollutants during pregnancy were estimated based on the daily average measured concentration levels from ground monitoring stations. Potential confounding factors including children-related, maternal, and socio-economic status (SES) were adjusted in the study. We calculated the prevalence of each type of behavioral difficulties and used binary logistic regression method to estimate the crude odds ratio (cOR), adjusted odds ratio (aOR), and corresponding 95% confidence intervals (95% CIs) for 1 μg/m³ increase in each air pollutant during every exposure window in single- and two-pollutant models. The prevalence of participants’ total behavioral difficulties was 9.6%. In single-pollutant models, during full gestation, positive associations were observed between exposure to NO₂ (aOR = 1.204, 95% CI 1.042, 1.392), particle matter (PM)₁₀ (aOR = 1.070, 95% CI 1.018, 1.125), PM₂.₅ (aOR = 1.095, 95% CI 1.021, 1.176) and total difficulties, exposure to PM₁₀ (aOR = 1.040, 95% CI 1.001, 1.081), PM₂.₅ (aOR = 1.053, 95% CI 1.000, 1.109) and prosocial behavior, respectively. In the first trimester, exposure to SO₂ (aOR = 1.047, 95% CI 1.009, 1.086), NO₂ (aOR = 1.039, 95% CI 1.013, 1.066), PM₁₀ (aOR = 1.013, 95% CI 1.004, 1.023), and PM₂.₅ (aOR = 1.016, 95% CI 1.004, 1.028) were all positively associated with total difficulties. The associations between second and third trimesters’ exposure to all pollutants and outcomes were not statistically significant. However, in the two-pollutant models, second trimester exposure to PM₂.₅ (aOR = 1.078, 95%CI 1.023, 1.137) was positively associated with total behavioral difficulties after adjusting for PM₁₀. Exposure to outdoor air pollutants SO₂, NO₂, PM₁₀, and PM₂.₅ during pregnancy may be associated with behavioral difficulties, especially in the first trimester.
Afficher plus [+] Moins [-]Levels of heavy metals in a multifloral Saudi honey
2019
Bazeyad, Abdulqader Y. | Al-Sarar, Ali S. | Rushdi, Ahmed I. | Hassanin, Ashraf S. | Abobakr, Yasser
The presence of chemical pollutants, especially heavy metals, affects the quality of honey. The objective of this study was to determine the levels of eight heavy metals (As, Cd, Co, Cr, Cu, Ni, Pb, and Zn) in honey samples from Al-Baha region in Saudi Arabia, using inductively coupled plasma with optical emission spectroscopy (ICP-OES). The highest concentration was found for Zn (1707.93 μg kg⁻¹), while the lowest was found for Co (3.04 μg kg⁻¹). Cluster analysis and principal component analysis showed that two groups are recognized indicating two different metal sources. The first group includes only Zn and the second group includes the rest of the metals. In view of the recommended and established heavy metal intakes for humans, consumption of Saudi honey from Al-Baha should not be deemed a matter of concern for human health.
Afficher plus [+] Moins [-]Improvement and application research of the SRM in alpine regions
2019
Hao, Gai-rui | Li, Jia-ke | Li, Kang-bin | Huang, Gang | Song, Jia-bao | Li, Huai-en
The simulation of snowmelt runoff in alpine mountainous areas is of great significance not only for the risk assessment of snowmelt flood in spring and summer, but also for the development and management of water resources in the basin. An improved snowmelt runoff model (SRM) is constructed based on the analysis of change characteristics of climate, runoff, and snow and ice cover in the middle and upper reaches of the Taxkorgan River in Xinjiang Province, China. Because of the large evaporation in the study basin, the evaporation loss is added to the model. The SRM and the improved SRM are calibrated and verified by using data such as temperature, precipitation, water vapor pressure, and snow-covered area (SCA) ratio in the study basin from 2002 to 2012. The results show that, compared with the SRM, the average Nash–Sutcliffe coefficient (NSE) of annual runoff simulation increases from 0.80 to 0.86 in the calibration and increases from 0.74 to 0.83 in the validation through the improved model, and the average runoff error reduces from − 12.8 to 1.32% in the calibration and reduces from − 20.0 to − 11.51% in the validation. After adding the measured flow rate for real-time correction, the average NSE of annual runoff simulation increases from 0.91 to 0.93 and the average annual runoff error reduces from − 7.76 to − 3.91% in the calibration. The average NSE increases from 0.85 to 0.89 and the average runoff error reduces from − 12.35 to − 2.76% in the validation. It indicates that the SRM structure with increased evaporation loss is more in line with the actual situation. The short-term simulation effect of the model is greatly improved by adding the measured flow rate for real-time correction. At the same time, the improved SRM and the hypothetical climate change scenario are used to analyze the impact analysis of the snowmelt runoff simulation in the partial wet year. The results show that in the case of rising temperature, the ice and snow ablation period is prolonged, and the annual runoff also changes significantly in time distribution. It is of guiding significance for the influence of climate change on the runoff of recharged rivers with ice–snow meltwater in the other alpine regions.
Afficher plus [+] Moins [-]COP negotiations and Malaysian climate change roadmap: a comparative assessment using a dynamic environmental model
2019
Ahmed, Adeel | Al-Amin, Abul Quasem | Rasiah, Rajah
This study critically evaluates two COP proposals on Malaysia that have been under consideration to reduce climate damage. A top-down disaggregation framework deploying an “Empirical Regional Downscaling Dynamic Integrated Model of Climate and the Economy” is used to evaluate the local government climate roadmap and Malaysia’s emissions reduction agendas under COP21 and subsequently COP22 proposals. The findings show that the costs from climate damage over the period 2010–2110 under the Malaysian Optimal Climate Action scenario will amount to MYR5,483 (US$1589) billion. The commensurate climate damage costs under the COP21 and COP22 scenario would be MYR5, 264 (US$1526) billion. Thus, the effective proposal for reducing climate damage in Malaysia over the period 2010–2110 is the COP22 time-adjusted COP21 proposal but there are a number of macroeconomic cost implications for savings and consumption that policy makers must address before acting.
Afficher plus [+] Moins [-]The role of eco-innovation on CO2 emission reduction in an extended version of the environmental Kuznets curve: evidence from the top 20 refined oil exporting countries
2019
Fethi, Sami | Rahuma, Abdulhamid
This study empirically investigates the role of eco-innovation on the reduction of carbon dioxide emissions (CO₂) in an extended version of the environmental Kuznets curve (EKC). Under dynamic framework, second-generation panel econometric techniques such as the CADF and the CIPS unit root tests, DSUR cointegrating test, and DH panel causality test are employed over the period 2007–2016 for the case of top 20 refined oil exporting countries. Results reveal that eco-innovation (i.e. research and development) exerts a negative and significant long-term effect on carbon emissions (CO₂). This result indicates that the extended version of EKC and the Porter hypotheses are validated for the selected countries. The findings, which show heterogeneity and cross-sectionally dependence in the panel time-series framework, suggest that rising levels of carbon emissions and real income may encourage more research and development (i.e. eco innovation) and lower energy consumption.
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