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1.
An investigation of ambient air quality was undertaken at three communities within the Athabasca Oil Sands Region (AOSR) of Alberta, Canada (Fort McKay, Fort McMurray, and Fort Chipewyan). Daily and seasonal patterns and 15-year trends were investigated for several criteria air pollutants over the period of 1998 to 2012. A parametric trend detection method using percentiles from frequency distributions of 1 h concentrations for a pollutant during each year was used. Variables representing 50th, 65th, 80th, 90th, 95th and 98th percentile concentrations each year were identified from frequency distributions and used for trend analysis. Small increasing concentration trends were observed for nitrogen dioxide (< 1 ppb/year) at Fort McKay and Fort McMurray over the period consistent with increasing emissions of oxides of nitrogen (ca. 1000 tons/year) from industrial developments. Emissions from all oil sands facilities appear to be contributing to the trend at Fort McKay, whereas both emissions from within the community (vehicles and commercial) and oil sands facility emissions appear to be contributing to the trend at Fort McMurray. Sulfur dioxide (SO2) emissions from industrial developments in the AOSR were unchanged during the period (101,000 ± 7000 tons/year; mean ± standard deviation) and no meaningful trends were judged to be occurring at all community stations. No meaningful trends occurred for ozone and fine particulate matter (PM2.5) at all community stations and carbon monoxide at one station in Fort McMurray. Air quality in Fort Chipewyan was much better and quite separate in terms of absence of factors influencing criteria air pollutant concentrations at the other community stations.  相似文献   

2.
10 household products, eight waxes or polishes, and two detergents have been screened by a headspace technique for the emission of volatile organic compounds (VOC). Using Tenax sampling and analysis by combined gas chromatography-mass spectrometry (GC-MS) more than 80 single compounds or groups of isomers have been identified, and semiquantitative data on the initial emission rates (emission rate immediately after application) have been obtained. Products fall into two groups: those containing water as a main (80 to 90%) constituent and those without water. The initial emission rate of the first group ranged from 0.2 to 2 μg cm−2min−1, whereas the second group had higher emission rates of up to 430 μg cm−2min−1. Products of the second group emit essentially hydrocarbons (alkanes, alkenes, and terpenes), whereas most products of the first group emit oxygenated compounds including terpene alcohols and their acetates, aliphatic alcohols and esters, and alkoxy-alcohols.  相似文献   

3.
A novel technique, gas chromatography-UV spectrometry (GC-UV), was used to quantify volatile organic compounds (VOCs) in settled dust from 389 residences in Sweden. The dust samples were thermally desorbed in an inert atmosphere and evaporated compounds were concentrated by solid phase micro extraction and separated by capillary GC. Eluting compounds were then detected, identified, and quantified using a diode array UV spectrophotometer. Altogether, 28 compounds were quantified in each sample; 24 of these were found in more than 50% of the samples. The compounds found in highest concentrations were saturated aldehydes (C5-C10), furfuryl alcohol, 2,6-di-tert-butyl-4-methylphenol (BHT), 2-furaldehyde, and benzaldehyde. Alkenals were also found, notably 2-butenal (crotonaldehyde), 2-methyl-propenal (methacrolein), hexenal, heptenal, octenal, and nonenal. The concentrations of each of the 28 compounds ranged between two to three orders of magnitude, or even more. These results demonstrate the presence of a number of VOCs in indoor dust, and provide, for the first time, a quantitative determination of these compounds in a larger number of dust samples from residents. The findings also illustrate the potential use of GC-UV for analysing volatile compounds in indoor dust, some of which are potential irritants (to the skin, eyes or respiratory system) if present at higher concentrations. The potential use of GC-UV for improving survey and control of the human exposure to particle-bound irritants and other chemicals is inferred.  相似文献   

4.
The presence of selected volatile organic compounds (VOCs) including aromatic, aliphatic compounds and low molecular weight carbonyls, and a target set of phthalates were investigated in the interior of 23 used private cars during the summer and winter. VOC concentrations often exceeded levels typically found in residential indoor air, e.g. benzene concentrations reached values of up to 149.1 µg m− 3. Overall concentrations were 40% higher in summer, with temperatures inside the cars reaching up to 70 °C. The most frequently detected phthalates were di-n-butyl-phthalate and bis-(2-ethylhexyl) phthalate in concentrations ranging from 196 to 3656 ng m− 3.  相似文献   

5.
Methods for determining individual exposure to volatile organic compounds (VOC) during normal daily activities were field tested on university student volunteers in Texas and North Carolina. The equipment tested included a personal monitor employing Tenax GC® to collect organic vapors for later analysis by GC-MS, and a specially designed spirometer for collecting samples of expired human breath on duplicate Tenax cartridges. The personal monitor and spirometer proved feasible for collecting abundant quantitative data on most of the 15 target organics. Air exposures to many VOC varied widely, sometimes over three orders of magnitude, among students on the same campus who had been monitored over the same time period and day. A log-linear relationship between breathing-zone air exposures and concentrations in exhaled breath was suggested for three chemicals: tetrachloroethylene, 1,1,1-trichloroethane, and vinylidene chloride. Air was the main route of exposure for all target compounds except the two trihalomethanes (chloroform and bromodichloromethane), which were transmitted mainly through water. Estimated total daily intake through air and water of the target organics ranged from 0.3 to 12.6 mg, with 1,1,1-trichloroethane at the highest concentrations in both geographic areas.  相似文献   

6.
This study focuses on characterising the risk of exposure to volatile organic compounds (VOCs) by means of inhalation in people living in the vicinity of the largest chemical production site in the Mediterranean area. Eighty-six VOCs were initially selected for this study based on their adverse environmental and health effects. The monitoring campaign was conducted for 276 days in three different locations around the chemical site. The analytical method used for the characterisation was based on European standard method EN-14662-2, which consists of the active sampling of air for 24 h in charcoal tubes, followed by extraction with carbon disulphide and GC-MS analysis. Forty-four VOCs with toxicological data available concerning their carcinogenic and non-carcinogenic health effects were quantified during the monitoring campaign. None of the quantified VOCs showed average concentrations exceeding their chronic reference concentrations and, therefore, no non-carcinogenic health effects are expected as a result of this exposure. However, the global average cancer risk due to VOC exposure in the area (3.3 × 10− 4) was found to be above the values recommended by the WHO and USEPA.The influence of the analytical method was also evaluated by comparing cancer risk estimates using a thermal desorption (TD) method based on method EN-14662-1. The results of the 24-h samples for the solvent extraction method were compared with the average of 12 daily samples of 2-h for the TD method for 24 sampling days. Although the global estimated lifetime cancer risk was statistically comparable for both methods, some differences were found in individual VOC risks.To our knowledge, this is the first study that estimates the carcinogenic and non-carcinogenic risks posed by the inhalation of VOCs in people living near a chemical site of this size, and compares the estimated cancer risk obtained using two different standard analytical methods.  相似文献   

7.
Climate change generally requires species to migrate northward or to higher elevation to maintain constant climate conditions, but migration requirement and migration capacity of individual species can vary greatly. Individual populations of species occupy different positions in the landscape that determine their required range shift to maintain similar climate, and likewise the migration capacity depends on habitat connectivity. Here, we demonstrate an approach to quantifying species vulnerabilities to climate change for 419 rare vascular plants in Alberta, Canada, based on a multivariate velocity of climate change metric, local habitat fragmentation, and migration capacity. Climate change velocities indicated that future migration requirements ranged from 1 to 5 km/year in topographically complex landscapes, such as the Alberta Foothills and Rocky Mountains. In contrast, migration requirements to maintain constant climate in relatively flat Boreal Plains, Parkland, and Grassland ranged from 4 to 8 km/year. Habitat fragmentation was also highest in these flat regions, particularly the Parkland Natural Region. Of the 419 rare vascular plants assessed, 36 were globally threatened (G1–G3 ranking). Three globally threatened species were ranked as extremely vulnerable and five species as highly vulnerable to the interactions among climate change velocity, habitat fragmentation, and migration capacity. Incorporating dispersal characteristics and habitat fragmentation with local patterns in climate change velocity improves the assessment of climate change threats to species and may be applied to guide monitoring efforts or conservation actions.  相似文献   

8.
Introduction: The aims of the present study are to assess the temporal trends of organochlorine compounds (OCs) concentrations and total serum burdens from birth until adolescence and the influence of breastfeeding in these temporal trends. Methods: In 1997 two birth cohort studies were set up in Ribera d'Ebre (N = 102) and the island of Menorca (N = 482), Spain. Concentrations (ng/mL) of OCs [pentachlorobenzene (PeCB), four isomers of hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (4,4′-DDT), dichlorodiphenyldichloroethylene (4,4′-DDE) and seven polychlorobiphenyl congeners (Σ7PCBs)] were measured in cord blood and at the age of 4 and 14 years. The total serum burdens (ng) of these compounds were estimated based on the total blood volume (mL) of children at the different ages. We compared median concentrations and total serum burdens of these OCs at the different time-points of follow-up between children of Ribera d'Ebre and Menorca and between breastfed and non-breastfed children. Results: From birth until adolescence concentrations of all OCs drastically reduced. These reductions were mainly derived from the dilution of OCs, associated to an increase in total blood volume of children at the age of 4 and 14 years. Despite the reduction in OCs concentrations, the total serum burdens of 4,4′-DDE and Σ7PCBs, were higher in adolescents than at birth. Increases in OCs total serum burden occurred both in breastfed and non-breastfed children, but were significantly higher in the first. Conclusions: Even after decades of banning OCs production and use, current young generations in westernized countries are still bioaccumulating these compounds. Given the potential health effects of OCs, especial attention should be paid in the control of secondary emissions in the environment and in the control of food production and contamination. In countries with endemic malaria it is important to work towards effective alternatives to the use of DDT.  相似文献   

9.
The cabin of an automobile can be considered to be a part of the living environment because many people spend long periods of time during business, shopping, recreation or travel activities. However, little is known about the interior air contamination due to organic compounds diffusing from the interior materials used in the interior of automobiles. In the present study, the compounds in the interior air of a new car were identified, and the time courses of their concentrations were examined for over 3 years after the delivery (July, 1999). A total of 162 organic compounds, involving many aliphatic hydrocarbons and aromatic hydrocarbons, were identified. High concentrations of n-nonane (458 microg/m(3) on the day following delivery), n-decane (1301 microg/m(3)), n-undecane (1616 microg/m(3)), n-dodecane (716 microg/m(3)), n-tridecane (320 microg/m(3)), 1-hexadecene (768 microg/m(3)), ethylbenzene (361 microg/m(3)), xylene (4003 microg/m(3)) and 2,2'-azobis(isobutyronitrile) (429 microg/m(3)) were detected, and the sum of the concentrations determined for all compounds excluding formaldehyde (TVOC) was approximately 14 mg/m(3) on the day after the delivery. The concentrations of most compounds decreased with time, but increased with a rise of the interior temperature. The TVOC concentration in the next summer (July, 2000) was approximately one-tenth of the initial concentration. During the 3-year study period, the TVOC concentrations in summer exceeded the indoor guideline value (300 mug/m(3)) proposed by [Seifert B. Volatile organic compounds. In: Maroni M, Seifert B, Lindvall T, editors. Indoor air quality. A comprehensive reference book. Air quality monographs, vol. 3. Netherlands: Elsevier Science; 1995. p. 819-21]. The interior temperature and days lapsed after delivery were the main factors affecting the interior concentrations of most compounds according to multiple linear regression analysis. The results of this study offer useful fundamental data for investigations on air pollution in automotive cabins due to the organic compounds diffusing from the interior materials.  相似文献   

10.
Concentration of radionuclides 210Pb and 7Be, having half lives of 22.3 years and 53.29 days, respectively, in the surface air samples of Islamabad (33.38° N, 73.10° E and Altitude ∼536 m asl.) are measured. The non-destructive technique of gamma-spectrometry, with a high purity germanium HPGe detector, was employed for the analysis of all samples. The annual average concentrations of 210Pb and 7Be in the surface air samples were determined as 0.284 ± 0.15 and 3.171 ± 1.14 mBq m−3, respectively. Our results have shown a seasonal variation of the concentration of 7Be in air samples with high values for the spring season. High concentrations for 210Pb are obtained when air masses originate from plain areas of Pothohar region, located in the South-West, West and North West of Islamabad. Our values of concentrations show a nice agreement with the relevant reported results.  相似文献   

11.
Lake Ontario water and sediment collected from tributary, nearshore, and open lake sites were analyzed for perfluoroalkyl substances (PFASs), namely perfluoroalkyl carboxylic acids (PFCAs, F(CF2)nCO2; n = 6-11,13) and perfluoroalkane sulfonic acids (PFSAs, F(CF2)nSO3; n = 6,8,10). Survey results of surface sediment and water indicated that shorter chained PFASs were predominant in and near urban/industrial area watersheds, while longer chained PFASs were predominant in fine-grained sediment from major depositional basins. Niagara River suspended solids (1981–2006) demonstrated temporal trends that may have been influenced by recent changes in North American production and use of PFASs. Perfluorooctane sulfonate (PFOS) reached a peak concentration in 2001 of 1.1 ng/g, followed by a decrease from 2001 to 2006 (half-life = 9 years). Perfluorooctanoic acid (PFOA) increased from 2001 to 2006 (doubling time = 2 years) reaching a peak concentration of 0.80 ng/g. In contrast, three sediment cores from western, central, and eastern Lake Ontario showed increasing temporal trends to surface sediment for all PFASs. PFOA and PFOS concentrations increased from 1988 to 2004 (doubling time = ~ 4 years) in the western Lake Ontario core. The observed variations in temporal trends from different environmental compartments may be a result of the physico-chemical properties of PFASs, ongoing emissions, and the environmental transformation and degradation of PFAS precursor compounds.  相似文献   

12.
Few population studies have measured urinary levels of pesticides in individuals with vegan, vegetarian, or organic diets. The objectives of this study were to evaluate whether a vegan/vegetarian diet was associated with increased exposure to organophosphate and carbamate pesticides, and to evaluate the impact of organic consumption on pesticide exposure in vegans and vegetarians. In the current pilot study conducted in 2013–2014, we collected spot urine samples and detailed 24 h recall dietary data in 42 adult residents of Amirim, a vegetarian community in Northern Israel. We measured urinary levels of non-specific organophosphate pesticide metabolites (dialkylphosphates, (DAPs)) and specific metabolites of the current-use pesticides chlorpyrifos (3,5,6-trichloro-2-pyridinol (TCPy)), propoxur (-isopropoxyphenol (IPPX)), and carbaryl (1-naphthol). Six DAP metabolites were detected in between 67 and 100% of urine samples, with highest geometric mean concentrations for dimethylphosphate (19.2 μg/g). Creatinine-adjusted median concentrations of total DAPs and of TCPy were significantly higher in Amirim residents compared to the general Jewish population in Israel (0.29 μmol/g compared to 0.16, p < 0.05 for DAPs and 4.32 μg/g compared to 2.34 μg/g, p < 0.05 for TCPy). Within Amirim residents, we observed a positive association between vegetable intake and urinary TCPy levels (rho = 0.47, p < 0.05) and lower median total dimethyl phosphate levels in individuals reporting that > 25% of the produce they consume is organic (0.065 μmol/L compared to 0.22, p < 0.05). Results from this pilot study indicate relatively high levels of urinary organophosphate pesticide metabolite concentrations in residents of a vegetarian community, a positive association between vegetable intake and urinary levels of a chlorpyrifos specific metabolite, and lower levels of total dimethyl phosphate in individuals reporting higher intake of organic produce. Results suggest that consumption of organic produce may offer some protection from increased exposure to organophosphate pesticide residues in vegetarians.  相似文献   

13.
14.
BackgroundSurveys of human exposure to environmental chemicals do not integrate the number of compounds detected per person and the concentration of each compound. This leaves untested relevant exposure scenarios, such as whether individuals with low concentrations of some compounds have high concentrations of the other compounds.ObjectiveTo analyze the number of persistent organic pollutants (POPs) detected at high concentrations.MethodsSerum concentrations of 19 POPs were analyzed by gas chromatography with electron-capture detection in a representative sample of the general population of Catalonia, Spain (N = 919).ResultsOver 58% of participants had concentrations in the top quartile of ≥ 1 of the eight most prevalent POPs, and 34% of ≥ 3 POPs. 83% of women 60 to 74 years old had concentrations of ≥ 3 POPs in the top quartile; 56% of women 60 to 74 years had p,p′-DDE, HCB and β-HCH all in their respective top quartiles, and 48% had concentrations of ≥ 6 POPs in the top quartile. Over 30% of subjects had concentrations in the top decile of 1 to 5 of the eight most prevalent POPs. Half of the population had levels of 1 to 5 POPs > 500 ng/g. Less than 4% had all eight POPs in the lowest quartile.ConclusionsMore than half of the study population had concentrations in the top quartile of ≥ 1 POPs. Significant subgroups of the population accumulate POP mixtures at high concentrations. POP concentrations appear low in most of the population only when each individual compound is looked at separately.  相似文献   

15.
Communities of Wood-Attacking Fungi in the Region of Oil and Gas Production   总被引:1,自引:0,他引:1  
The communities of xylotrophic fungi were studied in the northern and middle taiga subzones of western Siberia, in forests growing in the region of oil and gas production and exposed to various anthropogenic factors (emissions of petroleum gas flares, oil pollution, spills of mineralized oil-field water, etc.). Structural and functional rearrangements in these communities were revealed, and the prevalence of rot in the tree stand was assessed.  相似文献   

16.
Comparative analyses for aqueous chlorine using Standard Methods indicated that in chlorinated solutions containing nitrogenous organic compounds, none of these methods gave a reliable measurement of free available chlorine. Examination of the cyanuric acid-aqueous chlorine system showed that combined chlorine reacted as if it were free chlorine in all the Standard Methods. The implication of these studies for water and wastewater chlorination is that in waters containing nitrogenous organic compounds, N-Chloro compounds form which may result in an overestimation of the disinfecting potential of the added chlorine, when free chlorine is measured by Standard Methods.  相似文献   

17.
Assessing the adverse effects on human health of persistent organic pollutants (POPs) and the impact of policies aiming to reduce human exposure to POPs warrants monitoring body concentrations of POPs in representative samples of subjects. While numerous ad hoc studies are being conducted to understand POPs effects, only a few countries are conducting nationwide surveillance programs of human concentrations of POPs, and even less countries do so in representative samples of the general population. We tried to identify all studies worldwide that analyzed the distribution of concentrations of POPs in a representative sample of the general population, and we synthesized the studies' main characteristics, as design, population, and chemicals analyzed. The most comprehensive studies are the National Reports on Human Exposure to Environmental Chemicals (USA), the German Environmental Survey, and the Arctic Monitoring and Assessment Programme. Population-wide studies exist as well in New Zealand, Australia, Japan, Flanders (Belgium) and the Canary Islands (Spain). Most such studies are linked with health surveys, which is a highly-relevant additional strength. Only the German and Flemish studies analyzed POPs by educational level, while studies in the USA offer results by ethnic group. The full distribution of POPs concentrations is unknown in many countries. Knowledge gaps include also the interplay of age, gender, period and cohort effects on the prevalence of exposures observed by cross-sectional surveys. Local and global efforts to minimize POPs contamination, like the Stockholm convention, warrant nationwide monitoring of concentrations of POPs in representative samples of the general population. Results of this review show how such studies may be developed and used.  相似文献   

18.
19.
We aimed to characterize levels of polyfluorinated compounds (PFCs) in indoor dust from offices, homes, and vehicles; to investigate factors that may affect PFC levels in dust; and to examine the associations between PFCs in dust and office workers' serum. Dust samples were collected in 2009 from offices, homes, and vehicles of 31 individuals in Boston, MA and analyzed for nineteen PFCs, including perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), fluorotelomer alcohols (FTOHs), and sulfonamidoethanols (FOSEs). Serum was collected from each participant and analyzed for eight PFCs including PFOA and PFOS. Perfluorononanoate, PFOA, perfluoroheptanoate, perfluorohexanoate, PFOS and 8:2 FTOH had detection frequencies > 50% in dust from all three microenvironments. The highest geometric mean concentration in office dust was for 8:2 FTOH (309 ng/g), while PFOS was highest in homes (26.9 ng/g) and vehicles (15.8 ng/g). Overall, offices had the highest PFC concentrations, particularly for longer-chain carboxylic acids and FTOHs. Perfluorobutyrate was prevalent in homes and vehicles, but not offices. PFOA serum concentrations were not associated with PFC dust levels after adjusting for PFC concentrations in office air. Dust concentrations of most PFCs are higher in offices than in homes and vehicles. However, indoor dust may not be a significant source of exposure to PFCs for office workers. This finding suggests that our previously published observation of an association between FTOH concentrations in office air and PFOA concentrations in office workers was not due to confounding by PFCs in dust.  相似文献   

20.
Intrapopulation diversity and correlations of 30 volatile compounds in needles have been studied in Scots pine populations of southern Siberia. Significant differences between populations have been revealed in the correlation pattern of relative terpenoid contents in needle samples. Stable combinations of closely associated mono- and sesquiterpenes and specific features of the general pattern of correlations between relevant characters have been determined.  相似文献   

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