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131.
Polycyclic aromatic hydrocarbons (PAHs) were analysed in mosses (Hypnum cupressiforme) and pine needles (Pinus sylvestris) collected in the Czech Republic between 1988-94 at a regional background site in Kosetice, south Bohemia (1988-94) and two industrial sources. One industrial site (sampled 1989-91) in middle Moravia, was near a factory producing PAHs, carbon black and phthalates, the other (sampled 1991-93) near a coal and gas fuel production plant in western Bohemia. Selected chlorinated pesticides and polychlorinated biphenyl congeners were also analysed in samples at the regional background site. This study clearly shows that vegetation sampling can be used to show spatial differences in the atmospheric burden of a range of persistent organic pollutants with differences in the mixtures of compounds reflecting differences in their regional or local use/atmospheric emission.  相似文献   
132.
Modeling relationships between indoor and outdoor air quality   总被引:4,自引:0,他引:4  
Information about the ratio between indoor and outdoor concentrations (IO ratios) of air pollutants is a crucial component in human exposure assessment. The present study examines the relationship between indoor and outdoor concentrations as influenced by the combined effect of time patterns in outdoor concentrations, ventilation rate, and indoor emissions. Two different mathematical approaches are used to evaluate IO ratios. The first approach involves a dynamic mass balance model that calculates distributions of transient IO ratios. The second approach assumes a linear relationship between indoor and outdoor concentrations. We use ozone and benzene as examples in various modeling exercises. The modeled IO ratio distributions are compared with the results obtained from linear fits through plots of indoor versus outdoor concentrations.  相似文献   
133.
Environmental Science and Pollution Research - Environmental arsenic exposure in adults and children has been associated with a reduction in the expression of club cell secretory protein (CC16) and...  相似文献   
134.
Environmental Science and Pollution Research - In the current century, the G7 countries have attached more importance to energy security, and have prioritized low-carbon sources which have...  相似文献   
135.
Environmental Science and Pollution Research - The aquaculture industry is an efficient edible protein producer and grows faster than any other food sector. Therefore, it requires enormous amounts...  相似文献   
136.
Environmental Science and Pollution Research - The interaction and the interplay of climate change with oil palm production in the Southeast Asia region are of serious concern. This particularly...  相似文献   
137.
Environmental Science and Pollution Research - Methotrexate (MTX) and azathioprine (AZA) are chemotherapeutic, antimetabolic, and immunosuppressive agents with substantial risks such as oxidative...  相似文献   
138.
Environmental Science and Pollution Research - Increasing ultraviolet (UV) radiation is causing oxidative stress that accounts for growth and yield losses in the present era of climate change....  相似文献   
139.
Environmental Science and Pollution Research - The increasing intensification of the aquaculture industry requires the development of new strategies to reduce the negative impacts of wastewater on...  相似文献   
140.
Heavy metal pollution and forest health in the Ukrainian Carpathians   总被引:2,自引:0,他引:2  
The Ukrainian Carpathians are characterized by high air pollution caused by emissions from numerous industries. We have been monitoring the state of forests in this region since 1989. The highest levels of tree defoliation (>30%) are found close to industrial emission sources and in the upper mountain forests of the Ivano-Frankivsk and Chernivtsi regions. This is caused by a combination of strong anthropogenic influences (pollution, illegal uses, recreation) as well as poor site and climatic conditions. In the Ivano-Frankivsk region, Cd and Mo accumulate in forest soils; Cr, Mo and Zn soil concentrations are higher than their limit levels; and Pb concentrations exceed toxic levels close to industrial areas (10% of the region territory). Local background levels of heavy metals are greatly exceeded in snow close to industrial regions. Analysis of correlation matrices shows that the chemical elements Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, V and Zn occur at pollution levels in natural ecosystems in the Ukrainian Carpathians. Maximum concentrations of toxic elements occur in the oak forest zone; the most industrially developed area of the region. Toxic heavy metals in the Ukrainian Carpathians forests enter with precipitation and dustfall, then become fixed in soil and accumulate in leaves, needles of vascular plants and mosses. Concentrations of these metals decrease with altitude: highest in the oak forests, less in beech, and lowest in the spruce forest zones. However, some chemical elements have the highest concentrations in spruce forests; V in needles, As in snow, and Ba and Al in soils.  相似文献   
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