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601.
D. Bruce Henschel Roy C. Fortmann Nancy F. Roache Xiaoyu Liu 《Journal of the Air & Waste Management Association (1995)》2013,63(5):708-717
ABSTRACT A laboratory thermal desorption apparatus was used to measure emissions from a number of nominally identical photocopier toners—manufactured to meet the specifications of one specific model copier—when these toners were heated to fuser temperature (180-200 °C). The objective was to assess how potential volatile organic compound (VOC) emissions from the toner for a given copier can vary, depending upon the production run and the supplier. Tests were performed on a series of toner (and associated raw polymer feedstock) samples obtained directly from a toner manufacturer, representing two production runs using a nonvented extrusion process, and on toner cartridges purchased from two local retailers, representing three different production lots (histories unknown). The results showed that the retailer toners consistently had up to 350% higher emissions of some major compounds (expressed as |ig of compound emit-ted/g of toner), and up to 100% lower emissions of others, relative to the manufacturer toners (p ≤ 0.01). The manufacturer toners from one production run had emissions of certain compounds, and of total VOCs, that were modestly higher (13-18%) than those from the other run (p ≤ 0.01). The emission differences between the retailer and manufacturer toners are probably due to differences 相似文献
602.
603.
Petreas M Nelson D Brown FR Goldberg D Hurley S Reynolds P 《Environment international》2011,37(1):190-197
We measured major PBDEs and PCBs in breast adipose tissues of California women participating in a breast cancer study in the late 1990s. Samples were analyzed using gas chromatography with electron impact ionization and tandem mass spectrometry detection. The congener profile observed was: BDE47>BDE99>BDE153>BDE100>BDE154 and PCB153>PCB180>PCB138>PCB118. Whereas high correlations were observed within each chemical class, very weak correlations appeared between classes, pointing to different exposure pathways. Weak negative associations were observed for PBDE congeners and age. Our PBDE data are among the highest reported, exceeding data from the National Health and Nutrition Examination Survey and consistent with the high use of PBDEs in California. These data may be helpful in establishing a baseline for PBDE body burdens to gauge changes over time as a result of restrictions in the use of PBDE formulations. 相似文献
604.
Thomas PJ Mineau P Shore RF Champoux L Martin PA Wilson LK Fitzgerald G Elliott JE 《Environment international》2011,37(5):914-920
Second-generation anticoagulant rodenticides (SGARs) are widely used to control rodent pests but exposure and poisonings occur in non-target species, such as birds of prey. Liver residues are often analysed to detect exposure in birds found dead but their use to assess toxicity of SGARs is problematic. We analysed published data on hepatic rodenticide residues and associated symptoms of anticoagulant poisoning from 270 birds of prey using logistic regression to estimate the probability of toxicosis associated with different liver SGAR residues. We also evaluated exposure to SGARs on a national level in Canada by analysing 196 livers from great horned owls (Bubo virginianus) and red-tailed hawks (Buteo jamaicensis) found dead at locations across the country. Analysis of a broader sample of raptor species from Quebec also helped define the taxonomic breadth of contamination. Calculated probability curves suggest significant species differences in sensitivity to SGARs and significant likelihood of toxicosis below previously suggested concentrations of concern (<0.1mg/kg). Analysis of birds from Quebec showed that a broad range of raptor species are exposed to SGARs, indicating that generalised terrestrial food chains could be contaminated in the vicinity of the sampled areas. Of the two species for which we had samples from across Canada, great horned owls are exposed to SGARs to a greater extent than red-tailed hawks and the liver residue levels were also higher. Using our probability estimates of effect, we estimate that a minimum of 11% of the sampled great horned owl population is at risk of being directly killed by SGARs. This is the first time the potential mortality impact of SGARs on a raptor population has been estimated. 相似文献
605.
The Syracuse, NY, AUDIT (Assessment of Urban Dwellings for Indoor Toxics) study was designed to quantify asthma agent levels in the inner-city homes of a birth cohort whose mothers had a diagnosis of asthma. Risk of exposure to particulate matter (PM), particle number and tobacco smoke was assessed in 103 infants' homes. Repeat measurements were made in 44% of the homes. Infants also were examined on a quarterly basis during the first year of life to monitor their respiratory health and urine cotinine levels. Overall geometric mean (GM) values for PM(2.5) of 21.2 μg/m(3) and for PM(10) of 31.8 μg/m(3) were recorded in homes at visit 1. GM values for PM(2.5) and PM(10) in smoking homes were higher at 26.3 and 37.7 μg/m(3), while values in non-smoking homes were 12.7 and 21.2 μg/m(3) respectively. Fifty-four percent of mothers (55/103) smoked at some point in pregnancy (39% smoked throughout pregnancy). Environmental tobacco smoke (ETS) exposure occurred in 68% of homes during the infants' first year. Significant to this study was the size- and time-resolved monitoring of PM at 140 home visits and the classification of PM count data. PM number counts ranged from continuously low levels (little indoor activity) to continuously high counts (constant indoor activity), and recorded apparent instances of prolonged repeated cigarette smoking. Wheezing in the first year of life was recorded for 38% of the infants (39/103). Adjusted logistic regression modeling demonstrated that elevated levels of indoor PM(2.5) (≥ 15 μg/m(3)) were a significant risk factor for infant wheezing after controlling for infant gender, mothers' age and education level, season of home visit and presence of carpeting (OR 4.21; 95% CI 1.36-13.03; p=0.013). An elevated level of the nicotine metabolite cotinine in infant urine also was associated with infant wheezing after adjusting for infant gender, mothers' age and education level (OR 5.10; 95% CI 0.96-27.24; p=0.057). ETS exposure was pervasive in the AUDIT cohort and a risk for developing infants in this urban population. 相似文献
606.
de Nazelle A Nieuwenhuijsen MJ Antó JM Brauer M Briggs D Braun-Fahrlander C Cavill N Cooper AR Desqueyroux H Fruin S Hoek G Panis LI Janssen N Jerrett M Joffe M Andersen ZJ van Kempen E Kingham S Kubesch N Leyden KM Marshall JD Matamala J Mellios G Mendez M Nassif H Ogilvie D Peiró R Pérez K Rabl A Ragettli M Rodríguez D Rojas D Ruiz P Sallis JF Terwoert J Toussaint JF Tuomisto J Zuurbier M Lebret E 《Environment international》2011,37(4):766-777
607.
Iron and steel manufacture has been ranked as the largest industrial source of environmental contamination in the USA; the wastes generated in their production processes contain heavy elements that can be a source of contamination, and natural radionuclides that can produce an occupational and/or public radiological impact. In this work the potential occupational effective dose rate (μSv/y) due to inhalation in four integrated steel-making factories from Egypt has been evaluated, by assuming a well defined scenario and with basis in the 210Pb and 210Po activity concentrations determined in ore and wastes collected in the aforementioned factories. Activity concentrations, in Bq/kg, of 210Pb and 210Po, and leachable Pb and Fe were measured using gamma-ray spectrometry based on HPGe detector, alpha particle spectrometry based on PIPS detector, and inductively coupled plasma-mass spectrometry (ICP-MS). Levels of 210Pb and 210Po in the range of <DL-4238 and 1-5660 Bq/kg, respectively, were found. According to the assumed scenarios, the occupational exposures by inhalation are much lower than the recommended annual effective dose limit, although the environmental impact due to waste storage and/or use should be considered based on case by case evaluation. 相似文献
608.
Herranz M Romero LM Idoeta R Olondo C Valiño F Legarda F 《Journal of environmental radioactivity》2011,102(11):987-994
In this paper the inventory of 90Sr in 34 points distributed along the Spanish peninsular territory is presented. Obtained values range between 173 Bq/m2 and 2047 Bq/m2. From these data set and those 137Cs data obtained in a previous work the 137Cs/90Sr activity ratio has been established, laying this value between 0.9 and 3.6. Also the migration depth of both radionuclides has been analysed obtaining for 137Cs an average value 57% lower than that obtained for 90Sr.Additionally, this paper presents the results obtained in 11 sampling points in which the activity vertical profile has been measured. These profiles have been analysed to state the behaviour of strontium in soils and after, by using a convective-diffusive model, the parameters of the model which governs the vertical migration of 90Sr in the soil, v (apparent convection velocity) and D (apparent diffusion coefficient) have been evaluated. Mean values obtained are 0.20 cm/year and 3.67 cm2/year, respectively. 相似文献
609.
This study was conducted to identify the principle selenate carrier phases for two selected soils, by comparing their reactivity with selenate to that of pure phases of the solids. Silica, calcium carbonate, aluminium hydroxide, goethite, bentonite and humic acid were selected as the main soil carrier phases. Comparisons were made first on the parameter values obtained with the best fit of a kinetic sorption model which can discriminate instantaneous sorption from kinetically limited sorption. Then comparisons were made of the ability for each solid to stabilise selenate by measuring the ratio of the partition coefficient for sorption (Kdsorption) over that of the desorption (Kddesorption). Kinetics and stabilisation were used to help elucidate the nature of interactions with the test solid phases for a large range of selenate concentrations. The experiments were conducted over 165 h in batch reactors, the solid being isolated from the solution by dialysis tubing, at two pH (5.4 and 8) and three selenate concentrations (1 × 10−3, 1 × 10−6 and 1 × 10−8 mol L−1). The results obtained showed that only aluminium hydroxide can sorb selenate throughout the studied pH range (pH 5.4 to 8.0). The sorption capacity on this mineral was high (Kdsorption > 100 to 1 × 104 L kg−1) and the selenate was mainly stabilized by the formation of inner sphere complexes. The sorption on goethite occurred at pH 5.4 (Kdsorption 52 L kg−1), mainly as outer sphere complexes, and was null at pH 8. On silica, a weak sorption was observed only at pH 5.4 and at 165 h (Kdsorption 4 L kg−1). On bentonite, calcium carbonate and humic acid no significant sorption was observed. Concerning the two soils studied, different behaviours were observed for selenate. For soil Ro (pH 5.4), Kdsorption was low (8 L kg−1) compared to soil Bu (pH 8) (70 L kg−1). The sorption behaviour of selenate on soil Ro was mainly due to outer sphere complexes, as for goethite, whereas for soil Bu the sorption was mainly attributed to inner sphere complexes followed by reduction mechanisms, probably initiated by microorganisms, in which no steady state was reached at the end of the 165 h experiments. The sorption of selenate decreased when concentrations reached 1 × 10−3 mol L−1, due to solid saturation, except for aluminium hydroxide. Reduction of selenate seemed also to occur on goethite and soil Ro, for the same concentration, but without preventing a decrease in sorption. Thus, this work shows that the comparison of selenate behaviour between soil and pure phases helps to elucidate the main carrier phases and sorption mechanisms in soil. 相似文献
610.
Soil and biodiversity 总被引:1,自引:0,他引:1
F. Kh. Khaziev 《Russian Journal of Ecology》2011,42(3):199-204
It is shown that the soil diversity-biodiversity system in terrestrial ecosystems operates in spatiotemporal unity, which
manifests itself at different hierarchical levels of their structural-functional organization: successional-evolutionary,
zonal geographic, landscape, biogeocenotic, soil-type, horizon-layer, geochemical, and the levels of elementary soil processes
and soil fertility. Arguments confirming the functional relationship between organisms and soils are considered. Effective
biodiversity conservation is possible on the basis of an ecosystems approach involving simultaneous conservation of soil diversity. 相似文献