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1.
《Environment international》2012,38(8):1321-1328
The impact of cigarette smoking on volatile organic compound (VOC) blood levels is studied using 2003–2004 National Health and Nutrition Examination Survey (NHANES) data. Cigarette smoke exposure is shown to be a predominant source of benzene, toluene, ethylbenzene, xylenes and styrene (BTEXS) measured in blood as determined by (1) differences in central tendency and interquartile VOC blood levels between daily smokers [≥ 1 cigarette per day (CPD)] and less-than-daily smokers, (2) correlation among BTEXS and the 2,5-dimethylfuran (2,5-DMF) smoking biomarker in the blood of daily smokers, and (3) regression modeling of BTEXS blood levels versus categorized CPD. Smoking status was determined by 2,5-DMF blood level using a cutpoint of 0.014 ng/ml estimated by regression modeling of the weighted data and confirmed with receiver operator curve (ROC) analysis. The BTEXS blood levels among daily smokers were moderately-to-strongly correlated with 2,5-DMF blood levels (correlation coefficient, r, ranging from 0.46 to 0.92). Linear regression of the geometric mean BTEXS blood levels versus categorized CPD showed clear dose–response relationship (correlation of determination, R2, ranging from 0.81 to 0.98). Furthermore, the pattern of VOCs in blood of smokers is similar to that reported in mainstream cigarette smoke. These results show that cigarette smoking is a primary source of benzene, toluene and styrene and an important source of ethylbenzene and xylene exposure for the U.S. population, as well as the necessity of determining smoking status and factors affecting dose (e.g., CPD, time since last cigarette) in assessments involving BTEXS exposure.  相似文献   

2.
There is limited evidence about whether background exposure to organochlorine pesticides is related to impairment of cognitive function in general populations. This study was performed to investigate cross-sectional associations between serum concentrations of organochlorine pesticides and cognitive function, a predictor of dementia, among U.S. elders without overt dementia. Study subjects were 644 elders aged 60–85, participating in the National Health and Nutrition Examination Survey 1999–2002. We selected 6 organochlorine pesticides (p,p′-dichlorodiphenyltrichloroethane (DDT), p,p′-dichlorodiphenyldichloroethylene (DDE), trans-nonachlor, oxychlordane, heptachlor epoxide, and β-hexachlorocyclohexane) which were commonly detected in current general population. Cognitive function was assessed with the Digit-Symbol Substitution Test. All 6 compounds showed statistically significant or marginally significant inverse associations with cognitive score after adjusting for covariates including education levels. The strongest association was observed with p,p′-DDT. With the outcome of low cognitive score defined as < 25th percentile, elders in the highest quartile of p,p′-DDT, p,p′-DDE, and β-hexachlorocyclohexane had 2 to 3 times higher risks than those in the lowest quartile. In particular, when their concentrations were further divided with the cutoff points of 90th and 95th percentiles, p,p′-DDT in the highest 5th percentile showed 6.5 (95% confidence interval: 2.6–16.3) times higher risk of low cognitive score. On the other hand, non-persistent pesticides like organophosphates or pyrethroid showed little association with this cognitive score. The potential role of background exposure to organochlorine pesticides in the development of dementia should be explored in future prospective studies and in-vitro/in-vivo experimental studies.  相似文献   

3.
Regional Environmental Change - When established institutional pathways for energy efficiency policies necessary to mitigate climate change are blocked at the federal level, how do entrepreneurs in...  相似文献   

4.
Climate skepticism in the UK media has not been a major focus of recent research. This paper aims to help fill the gap by looking at the incidence of skeptical voices in UK newspapers across three periods: 2007, 2009/2010, and 2010/2011. After analyzing more than 3200 articles, it finds that skeptical voices increased their presence markedly across all newspapers and all types of articles in the second period, and maintained a significant presence in many in the third. Uncontested skeptical voices were particularly prevalent in opinion pieces and editorials in right-leaning newspapers in the second. It also finds that skeptical voices or opinions were more likely to be included in pieces written by in-house non-specialist columnists than by environment editors or correspondents. The negative implications of the results for public understanding and the quality of public debate are then explored.  相似文献   

5.
Chen  Yi  Wang  Pin  Zhang  Zhao  Tao  Fulu  Wei  Xing 《Regional Environmental Change》2017,17(8):2397-2408
Regional Environmental Change - Increasing population, limited land resources, and the demand for environmental protection highlight the urgency of improving crop yield on the limited cultivated...  相似文献   

6.
A quality-controlled and enhanced database of 38 temperature and 52 precipitation stations was developed for Slovenia, a transitional area between Mediterranean, Alpine and continental climatic regimes, covering the period 1951–2007. Mean annual temperatures significantly increased in nearly all of Slovenia (except western areas) at rates between 0.15 and 0.36 °C/decade. Warming was most intense strongest in summer and spring in north-eastern Slovenia (0.3–0.4 °C/decade) and weakest in autumn. Precipitation trends were heterogeneous. Annual precipitation decreased significantly in the north-western part, at 3–6 % per decade. During spring and summer, decrease in rainfall by 3–6 % was detected in western Slovenia. No significant trends were found for the autumn season. In winter, precipitation decreased, by 3–12 % per decade, in particular in north-western Slovenia. As observed also elsewhere in Central Europe, changes in large-scale atmospheric circulation patterns may have contributed to the observed long-term warming and drying in Slovenia. However, the strong warming in summer and spring, that is almost twice the trend observed in neighbouring countries, could be enhanced by drier soils caused by the decrease in winter precipitation in Slovenia.  相似文献   

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8.
We aimed to estimate the levels and time trends of perfluorinated alkyl acids (PFAAs) in serum of 1533 Danish pregnant nulliparous women between 2008 and 2013. The selection criterion of only including nulliparous women was chosen to avoid confounding from parity. The serum samples were analyzed for sixteen PFAAs using solid phase extraction and liquid chromatography tandem mass spectrometry (LC-MS/MS). We investigated the time trends for seven PFAAs, which were detected in more than 50% of the samples: perfluorohexane sulfonate (PFHxS), perfluoroheptane sulfonate (PFHpS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnA). We found that the serum levels of all seven PFAAs decreased during the period from 2008 to 2013; on average PFHxS decreased with 7.0% per year, PFHpS with 14.8%, PFOS with 9.3%, PFOA with 9.1%, PFNA with 6.2%, PFDA with 6.3%, and PFUnA with 7.1% per year. Adjustment for maternal age, body mass index (BMI), educational level and gestational age at blood sampling did not change the time trends much. To our knowledge, we are the first to report decreasing trends of PFNA, PFDA and PFUnA since year 2000, thereby indicating that the phase-out of these compounds are beginning to show an effect on human serum levels.  相似文献   

9.
Climate change projections have drawn attention to the risks of extreme heat and the importance of public health interventions to minimise the impact. The city of Perth, Western Australia, frequently experiences hot summer conditions, with recent summers showing above average temperatures. Daily maximum and minimum temperatures, mortality, emergency department (ED) presentations and hospital admissions data were acquired for Perth for the period 1994 to 2008. Using an observed/expected analysis, the temperature thresholds for mortality were estimated at 34–36 °C (maximum) and 20 °C (minimum). Generalised estimating equations (GEEs) were used to estimate the percentage increase in mortality and morbidity outcomes with a 10 °C increment in temperature, with adjustment for air pollutants. Effect estimates are reported as incidence rate ratios (IRRs). The health impact of heatwave days (three or more days of ≥ 35 °C) was also investigated. A 9.8% increase in daily mortality (IRR 1.098; 95%CI: 1.007–1.196) was associated with a 10 °C increase in maximum temperature above threshold. Total ED presentations increased by 4.4% (IRR 1.044; 95%CI: 1.033–1.054) and renal-related ED presentations by 10.2% (IRR 1.102; 95%CI: 1.071–1.135) per 10 °C increase in maximum temperature. Heatwave days were associated with increases in daily mortality and ED presentations, while total hospital admissions were decreased on heatwave days. Public health interventions will be increasingly important to minimise the adverse health impacts of hot weather in Perth, particularly if the recent trend of rising average temperatures and more hot days continues as projected.  相似文献   

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Some important naturally occurring α- and β-radionuclides in drinking water samples collected in Italy were determined and the radiological quality evaluated. The mean activity concentrations (mBq L−1) of the radionuclides in the water samples were almost in the order: 26 ± 36 (234U) > 21 ± 30 (238U) > 8.9 ± 15 (226Ra) > 4.8 ± 6.3 (228Ra) > 4.0 ± 4.1 (210Pb) > 3.2 ± 3.7 (210Po) > 2.7 ± 1.2 (212Pb) > 1.4 ± 1.8 (224Ra) > 1.1 ± 1.3 (235U) > 0.26 ± 0.39 (228Th) > 0.0023 ± 0.0009 (230Th) > 0.0013 ± 0.0006 (232Th). The mean estimated dose (μSv yr−1) to an adult from the water intake was in this order: 2.8 ± 3.3 (210Po) > 2.4 ± 3.2 (228Ra) > 2.1 ± 2.1 (210Pb) > 1.8 ± 3.1 (226Ra) > 0.94 ± 1.30 (234U) > 0.70 ± 0.98 (238U) > 0.069 ± 0.087 (224Ra) > 0.036 ± 0.044 (235U) > 0.014 ± 0.021 (228Th) > 0.012 ± 0.005 (212Pb) > 0.00035 ± 0.00029 (230Th) > 0.00022 ± 0.00009 (232Th). It is obvious that 210Po, 228Ra, 210Pb and 226Ra are the most important dose contributors in the drinking water intake. As far as the seventeen brands of analysed drinking water were concerned, the committed effective doses were in the range of 2.81–38.5 μSv yr−1, all well below the reference level of the committed effective dose (100 μSv yr−1) recommended by the WHO. These data throw some light on the scale of the radiological impact on the public from some naturally occurring radionuclides in drinking water, and can also serve as a comparison for the dose contribution from artificial radionuclides released to the environment as a result of human practices. Based on the radionuclide composition in the analysed waters, comment was made on the new screening level for gross α activity in guidelines for drinking-water quality recommended by the WHO, 2004.  相似文献   

12.
Abstract

Water pollution is one of the major environmental problems, especially in urban areas. Due to rapid urban expansion and industrialization, water pollution in Zhengzhou City, the capital of Henan Province in central China has become a serious problem for its development. In this study, the surface water quality was evaluated using Nemerow Comprehensive Pollution Index (NCPI), and the change trend was calculated using methods of Mann-Kendall test and Sen’s slope estimator, based on the monitoring data from 1998 to 2008. The results show that the NCPI ranged from 3 to 50 in 70% of the monitoring cases, implying that most rivers were seriously polluted. However, this serious polltuon is expected to be gradually improved, as the concentration of water pollutants and NCPI declined significantly in most rivers. Water pollution in reservoirs was much lower than rivers, and the NCPI in the three monitored reservoirs was lower than 3 in most years, and shows a downward trend. Although the surface water quality was gradually improved, great efforts are still needed to enhance the protection and improvement of surface water environment.  相似文献   

13.
Temporal and spatial characteristics of dust storms in the Xilingol grassland of northern China were explored in this paper, based on data of dust storms from the China Meteorological Data Sharing Service System. During the period of 1954–2007, the total dust storm events (DSE) for the Xilingol grassland decreased from the 1960s to the 1990s, and abnormally increased in the 2000s with clear inter-annual and inter-decadal variations as well as spatial differences. The annual mean DSE in the northwest part was generally more than those in the southeast part of Xilingol grassland, with the DSE increasing significantly in the northwestern part of Xilingol grassland in 2000s. The wind speed has a weak correlation with frequency, duration time, and intensity of DSE during the last decades. The influence of spring vegetation condition on the frequency of DSE should be given more attention, especially in the northwest part of the Xilingol grassland. The threshold wind speeds of DSE in different sub-regions of the study area range between 7.0 and 12.8 m/s. Maximum 10-min average wind speeds during DSE tended to decline between 1980 and 2007. The abnormally frequent and strong DSE occurring with lower wind speeds in the 2000s were probably closely related to local vegetation change and serious desertification.  相似文献   

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Policy-making in social-ecological systems increasingly looks to iterative, evolutionary approaches that can address the inherent complexity of interactions between human wellbeing, provision of goods, and the maintenance of ecosystem services. Here, we show how the analysis of available time-series in tropical delta regions over past decades can provide important insight into the social-ecological system dynamics in deltaic regions. The paper provides an exploratory analysis of the recent changes that have occurred in the major elements of three tropical deltaic social-ecological systems, such as demography, economy, health, climate, food, and water. Time-series data from official statistics, monitoring programmes, and Earth observation data are analysed to explore possible trends, slow and fast variables, and observed drivers of change in the Amazon, Ganges–Brahmaputra–Meghna and Mekong deltas. In the Ganges–Brahmaputra–Meghna delta zone, increasing gross domestic product and per capita income levels since the 1980s mirror rising levels of food and inland fish production. In contrast, non-food ecosystem services, such as water availability, water quality, and land stability appear to be deteriorating. In the Amazon delta, natural and anthropogenic perturbations are continuously degrading key ecosystem services, such as carbon storage in biomass and soils, the regulation of water balance, and the modulation of regional climate patterns. In the Mekong delta, rapid economic development, changing land-use practices, and salinity intrusion are progressively putting more pressure on the delivery of important provisioning services, such as rice and inland aquaculture production, which are key sources of staple food, farm incomes, and export revenue. Observed changes in many key indicators of ecosystem services point to a changing dynamic state and increased probability of systemic threshold transformations in the near future.  相似文献   

16.
This paper aims to establish whether the longitudinal framing of climate change (CC) in Greek newspapers exhibits the characteristics of a “narrative cycle,” with different themes becoming prominent at different periods in accordance with the media’s narrative considerations. In order to test this assumption, we formulate a number of hypotheses which we test with data originating from three Greek newspapers over the period 2001–2008. We find that the scientific and ecological/meteorological themes of CC are more often mentioned during the initial phase of media coverage, arguably due to media’s attempt to open the narrative and capture the public’s attention. Public protests and debate feature more prominently during the peaked phase of coverage, in accordance with the narrative need for a climax, while the later period of coverage, when some kind of resolution to the story should be offered, is characterized by the prominence of policy-making and economy-related issues.  相似文献   

17.
Snow cover in Spanish mountains is crucial for ensuring water availability in spring and summer months, for the success of winter tourism or for the maintenance of biodiversity in mountain ecosystems. A changing climate may affect the volume of snow cover even in high mountains, where weather conditions are usually favorable for snow accumulation. In this paper, we aim to investigate the evolution (1970–2007) of combined precipitation–temperature modes in the Spanish mountains, and the sensitivity of the snowpack to their occurrence. The climatic database “Spain02” and snow thickness data for Spanish mountains were used for this purpose. Results showed that the frequency of dry-warm and wet-warm days has increased over time in all mountain ranges, while the frequency of the “cold” modes has decreased. The thickness of the snowpack in the Pyrenees has also decreased and its evolution is negatively correlated with the frequency of dry-warm days, and positively correlated with the frequency of dry-cold and wet-cold days. This work constitutes the first approach that relates the evolution of climatic conditions favorable or unfavorable for snow accumulation and the evolution of the snowpack in Spanish mountains.  相似文献   

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ObjectiveA recent longitudinal study reported an association between fine particulate (PM2.5) exposure and preterm birth (PTB) in a US cohort. We applied the same design to an Australian cohort to investigate associations with PTB and pre-labor rupture of membranes (PROM).MethodsFrom 287,680 births, we selected 39,189 women who had singleton births at least twice in Western Australia in 1997–2007 (n = 86,844 births). Analyses matched pregnancies to the same women with conditional logistic regression.ResultsFor PROM adjusted odds ratios (ORs) for a 1 μg/m3 increase in PM2.5 in the first trimester, second trimester, third trimester, and whole pregnancy were 1.00 (95% confidence interval (CI): 0.97, 1.03), 1.03 (95% CI: 1.00, 1.06), 1.02 (95% CI: 1.00, 1.05), and 1.02 (95% CI: 0.99, 1.05) respectively. For PTB, corresponding ORs were 1.00 (95% CI: 0.96, 1.04), 1.00 (95% CI: 0.96, 1.04), 0.98 (95% CI: 0.94, 1.02), and 0.99 (95% CI: 0.95, 1.04) respectively.ConclusionRisk of PROM was greater for pregnancies with elevated PM2.5 exposure in the second trimester than were other pregnancies to the same Australian women at lower exposure. There was insufficient evidence for an association with PTB, indicating that a longer time period might be needed to observe an association if a causal effect exists.  相似文献   

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