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Volatile organic compounds (VOCs) are found in indoor air, and many of these can affect human health (e.g. formaldehyde and benzene are carcinogenic). Plants affect the levels of VOCs in indoor environments, thus they represent a potential green solution for improving indoor air quality that at the same time can improve human health. This article reviews scientific studies of plants’ ability to remove VOCs from indoor air. The focus of the review is on pathways of VOC removal by the plants and factors affecting the efficiency and rate of VOC removal by plants. Laboratory based studies indicate that plant induced removal of VOCs is a combination of direct (e.g. absorption) and indirect (e.g. biotransformation by microorganisms) mechanisms. They also demonstrate that plants’ rate of reducing the level of VOCs is influenced by a number of factors such as plant species, light intensity and VOC concentration. For instance, an increase in light intensity has in some studies been shown to lead to an increase in removal of a pollutant. Studies conducted in real-life settings such as offices and homes are few and show mixed results.  相似文献   
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Dechlorane Plus (DP) has been determined in surface sediments from three Chinese coastal bays, e.g. Jiaozhou, Sishili and Taozi Bay in North China. DP concentrations ranged from <1.2 to 187 pg g−1 dry weight (dw) (mean: 24.7 pg g−1 dw) in Jiaozhou Bay, <1.2 to 135 pg g−1 dw (mean 69.9 pg g−1 dw) in Sishili Bay and <1.2 to 66.7 pg g−1 dw (mean: 40.4 pg g−1 dw) in Taozi Bay, respectively. Additionally, two dechlorinated species were quantified, which accounted for 0.6-5.1% of the ∑DP concentration.The fsyn values (syn-isomer/(syn- + anti-isomer)) in sediments from Jiaozhou Bay (mean 0.29) were close to the technical DP mixture (0.2-0.4), probably indicating local inputs of DP. In contrast, sediments in Sishili and Taozi Bay showed much lower fsyn values (mean 0.16). During transportation the DP isomers are subject to stereo selective degradation which partly resulted in the relative enrichment of anti-DP in coastal sediments.  相似文献   
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Air samples collected in the German part of the North Sea from March to July 2010 were investigated for organophosphorus compounds (OPs) being applied as flame retardants and plasticizers. The ∑8OPs concentration ranged from 110 to 1400 pg m−3 while tris(2-chloroisopropyl) phosphate (TCPP) dominated all samples with individual concentrations up to 1200 pg m−3. The highest concentrations were observed in continental air masses showing the high influence of industrialized regions including production sites on atmospheric emissions and concentrations. The occurrence of OPs even in oceanic/Arctic air masses shows that OPs can undergo long-range atmospheric transport. Dry particle-bound deposition fluxes from 9 to 240 ng m−2 d−1 for ∑8OPs were estimated leading to a minimum annual flux of 710 ± 580 kg y−1 OPs into the German North Sea. This study presents the first occurrence of OPs in the marine atmosphere together with important information on their long-range transport potential.  相似文献   
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In a series of 2961 consecutive cases with second-trimester biochemical triple screening for Down's syndrome and neural tube defect (NTD), ten (0.3 per cent) showed an apparent increased risk for both conditions. Three cases had chromosomal abnormalities, namely trisomy 16 confined to the placenta. Since placental trisomy 16 as well as cases with increased alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) are associated with (intrauterine growth retardation (IUGR), oligohydramnios, and fetal demise, at least some cases with this atypical biochemical profile could be explained by this chromosomal abnormality. From our results we recommend that in cases with increased risk for both Down's syndrome and NTD, fetal karyotyping should preferably be done on a placental biopsy, especially when ultrasound in the absence of anomalies demonstrates early IUGR.  相似文献   
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