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Assessment of present and future risk to Italian forests and human health: Modelling and mapping
2009
A review of ozone pollution in Italy shows levels largely above the thresholds established by EU regulation for vegetation and human health protection. The Italian air quality monitoring network appears quantitatively inadequate to cover all the territorial surface, because of scarcity and unequal distribution of monitoring sites. By applying the integrated assessment model RAINS-Italy to the year 2000, the whole of Italy exceeds the AOT40 critical level for forest, while Northern and central areas show strong potential of O3 impact on human health with 11% of territory >10 O3-induced premature deaths. Two scenarios for the year 2020, the Current Legislation and the Maximum Technical Feasible Reduction, show a reduction of AOT40Forest by 29% and 44%, SOMO35 by 31% and 47%, and O3-induced premature deaths by 32% and 48%, compared to 2000. RAINS-Italy can be used to improve the map quality and cover areas not reached by the national monitoring network. AOT40 and SOMO35 are and will be high enough to affect forest and human health all over Italy.
显示更多 [+] 显示较少 [-]Introducing an integrated climate change perspective in POPs modelling, monitoring and regulation
2009
This paper presents a review on the implications of climate change on the monitoring, modelling and regulation of persistent organic pollutants (POPs). Current research gaps are also identified and discussed. Long-term data sets are essential to identify relationships between climate fluctuations and changes in chemical species distribution. Reconstructing the influence of climatic changes on POPs environmental behaviour is very challenging in some local studies, and some insights can be obtained by the few available dated sediment cores or by studying POPs response to inter-annual climate fluctuations. Knowledge gaps and future projections can be studied by developing and applying various modelling tools, identifying compounds susceptibility to climate change, local and global effects, orienting international policies. Long-term monitoring strategies and modelling exercises taking into account climate change should be considered when devising new regulatory plans in chemicals management. Climate change implications on POPs are addressed here with special attention to monitoring, modelling and regulation issues.
显示更多 [+] 显示较少 [-]Mercury bioaccumulation and risk to three waterbird foraging guilds is influenced by foraging ecology and breeding stage
2009
We evaluated mercury (Hg) in five waterbird species representing three foraging guilds in San Francisco Bay, CA. Fish-eating birds (Forster's and Caspian terns) had the highest Hg concentrations in thier tissues, but concentrations in an invertebrate-foraging shorebird (black-necked stilt) were also elevated. Foraging habitat was important for Hg exposure as illustrated by within-guild differences, where species more associated with marshes and salt ponds had higher concentrations than those more associated with open-bay and tidal mudflats. Importantly, Hg concentrations increased with time spent in the estuary. Surf scoter concentrations tripled over six months, whereas Forster's terns showed an up to 5-fold increase between estuary arrival and breeding. Breeding waterbirds were at elevated risk of Hg-induced reproductive impairment, particularly Forster's terns, in which 48% of breeding birds were at high risk due to their Hg levels. Our results highlight the importance of habitat and exposure timing, in addition to trophic position, on waterbird Hg bioaccumulation and risk. The influence of foraging habitat, trophic position, and exposure timing on mercury bioaccumulation and risk to reproduction is evaluated in three waterbird guilds.
显示更多 [+] 显示较少 [-]Modelling the risk of Pb and PAH intervention value exceedance in allotment soils by robust logistic regression
2009
Soils of allotments are often contaminated by heavy metals and persistent organic pollutants. In particular, lead (Pb) and polycyclic aromatic hydrocarbons (PAHs) frequently exceed legal intervention values (IVs). Allotments are popular in European countries; cities may own and let several thousand allotment plots. Assessing soil contamination for all the plots would be very costly. Soil contamination in allotments is often linked to gardening practice and historic land use. Hence, we predict the risk of IV exceedance from attributes that characterize the history and management of allotment areas (age, nearby presence of pollutant sources, prior land use). Robust logistic regression analyses of data of Swiss allotments demonstrate that the risk of IV exceedance can be predicted quite precisely without costly soil analyses. Thus, the new method allows screening many allotments at small costs, and it helps to deploy the resources available for soil contamination surveying more efficiently. The contamination of allotment soils, expressed as frequency of intervention value exceedance, depends on the age and further attributes of the allotments and can be predicted by logistic regression.
显示更多 [+] 显示较少 [-]Volatile organic compounds from Italian vegetation and their interaction with ozone
2009
Volatile Organic Compounds (VOCs) emitted from vegetation (particularly isoprenoids) represent an important source of atmospheric hydrocarbons almost double the anthropogenic source. When biogenic VOC mix with NOx in the presence of UV radiation, ozone (O3) is formed. In Italy, optimal conditions for O3 formation in terms of VOC/NOx ratios and abundance of UV radiation occur for long periods of the year. Moreover, Italian vegetation includes several species that are strong and evergreen isoprenoid emitters, and high temperatures for part of the year further stimulate these temperature-dependent emissions. We review emission of isoprenoids from Italian vegetation, current knowledge on the impact of rising O3 levels on isoprenoid emission, and evidence showing that isoprenoids can increase both the O3 flux to the plant and protection against oxidative stress because of their antioxidant functions. This trait not only influences plant tolerance to O3 but also may substantially alter the flux of O3 between atmosphere and biosphere. The capacity to emit isoprenoids confers to plants tolerance to O3 and alters the flux of O3 between atmosphere and biosphere.
显示更多 [+] 显示较少 [-]Levels and distribution of polybrominated diphenyl ethers (PBDEs) in the freshwater environment surrounding a PBDE manufacturing plant in China
2009
Xu, Jie | Gao, Zishen | Xian, Qiming | Yu, Hongxia | Feng, Jianfang
Polybrominated diphenyl ethers (PBDEs) were determined in muscle, liver and eggs of freshwater fishes and surface sediments from the Nongkang River in Jinhu, Jiangsu Province, China. The present study is the first to report PBDE concentrations in the freshwater environment surrounding a PBDE manufacturing plant in China. The concentrations of 13 PBDE congeners in muscle, liver and eggs of freshwater fishes ranged from <LOD to 130, <LOD to 252 and <LOD to 33.3 ng/g lipid wt, respectively, while the concentrations of 13 PBDE congeners in surface sediments from sewage outfall, upstream and downstream of the river were 52, 9.2, 7.1 ng/g organic carbon wt, respectively. Contamination by PBDEs in this area was not serious when compared with other regions of the world. A relatively high proportion of BDE-183 was found, consistent with the octa-BDE technical mixtures from the manufacturing plant by the side of the river. The first study to report concentrations of PBDEs in the freshwater environment surrounding a PBDE manufacturing plant in China.
显示更多 [+] 显示较少 [-]Exposure assessment of French women and their newborn to brominated flame retardants: Determination of tri- to deca- polybromodiphenylethers (PBDE) in maternal adipose tissue, serum, breast milk and cord serum
2009
Antignac, Jean-Philippe | Cariou, Ronan | Zalko, Daniel | Berrebi, A (Alain) | Cravedi, Jean-Pierre | Maume, Daniel | Marchand, Philippe | Monteau, Fabrice | Riu, Anne | Andre, François
In the frame of a French monitoring program, tri- to deca- polybromodiphenylethers (PBDE) have been measured in maternal and cord serum, adipose tissue, and breast milk samples, collected from 93 volunteer women during caesarean deliveries. The seven major tri- to heptaBDE (BDE-28, 47, 99, 100, 153, 154, and 183) were detected in adipose tissue and breast milk with cumulated median values of 2.59 and 2.51 ng g-1 l w. Nine highly brominated octa- to decaBDE (BDE-196, 197, 201, 202, 203, 206, 207, 208 and 209) was performed in the same samples, with cumulated median values of 2.73 and 3.39 ng g-1 l w in adipose tissue and breast milk, respectively. At this opposite, median levels of octa- to decaBDE in maternal and cord serum appeared significantly higher than the levels of tri- to heptaBDE in the same matrices, i.e. 8.85 and 12.34 versus 0.98 and 0.69 ng g-1 l w, respectively. This study provides the first data at the French level regarding the occurrence of PBDE in human, and demonstrates the exposure of both human foetus at late stage of pregnancy and newborn at early stages of life through breastfeeding with special emphasis on the presence of highly brominated compounds.
显示更多 [+] 显示较少 [-]Gating in grapevine: Relationship between application of the fungicide fludioxonil and circadian rhythm on photosynthesis
2009
Petit, Anne-Noëlle | Fontaine, Florence | Clement, Christophe | Vaillant-Gaveau, Nathalie
The aim of this study was to determine the impact of the fludioxonil (fdx) fungicide on the diurnal fluctuation in grapevine photosynthesis. Therefore, fdx treatment was performed at the end of flowering, at 8 am, 12 am or 7 pm. The study was performed in experimental field and several photosynthesis parameters were followed one day after treatment. Morning fdx treatment induced (i) a significant and simultaneous drop of both photosynthesis (Pn) and stomatal conductance between 8 am and 4 pm and (ii) an increase of intercellular CO2 concentration when compared to control plants. On the contrary, evening fdx treatment did not affect Pn whereas midday treatment caused Pn increase after 4 pm. These data suggest that (i) morning fdx treatment results in a non-stomatal limitation of Pn, (ii) midday treatment is more suitable to treat grapevine with fdx and (iii) a phenomenon of gating was noticed. The period of fdx spraying was an important parameter in stress response: the midday fdx treatment is more suitable to treat grapevine with fdx.
显示更多 [+] 显示较少 [-]Application of encapsulation (pH-sensitive polymer and phosphate buffer macrocapsules): A novel approach to remediation of acidic ground water
2009
Aelion, C Marjorie | Davis, Harley T. | Flora, Joseph R.V. | Kirtland, Brian C. | Amidon, Mark B.
Macrocapsules, composed of a pH-sensitive polymer and phosphate buffer, offer a novel remediation alternative for acidic ground waters. To test their potential effectiveness, laboratory experiments were carried out followed by a field trial within a coal pile runoff (CPR) acidic contaminant plume. Results of traditional limestone and macrocapsule treatments were compared in both laboratory and field experiments. Macrocapsules were more effective than limestone as a passive treatment for raising pH in well water from 2.5 to 6 in both laboratory and field experiments. The limestone treatments had limited impact on pH, only increasing pH as high as 3.3, and armoring by iron was evident in the field trial. Aluminum, iron and sulfate concentrations remained relatively constant throughout the experiments, but phosphate increased (0.15-32 mg/L), indicating macrocapsule release. This research confirmed that macrocapsules may be an effective alternative to limestone to treat highly acidic ground water. Encapsulated phosphate buffer macrocapsules were more effective than limestone for passive treatment of acidic coal pile runoff (CPR) contaminated ground water, increasing pH from 2.5 to 6 in laboratory and field experiments.
显示更多 [+] 显示较少 [-]Hg concentrations and related risk assessment in coral reef crustaceans, molluscs and fish from New Caledonia
2009
Chouvelon, Tiphaine | Warnau, Michel | Churfaud, Carine | Bustamante, Paco
There is a dramatic lack of data on Hg levels in marine organisms from tropical areas, and in particular from New Caledonia. For the first time, this study reports the total Hg concentrations in the tissues of several marine taxa from the New Caledonian lagoon. Seafood from both wild and farmed populations was considered. Hg concentrations varied over three orders of magnitudes according to factors including species, age (size/weight), trophic level, lifestyle and geographical origin. Taking into account the edible tissues, estimations of the amount of flesh that should be consumed by a 60-kg person to reach the Hg Provisional Tolerable Weekly Intake (PTWI) reveal acceptable risk for Human health in general. However, a risk was clearly identified in one site of the lagoon (i.e. Grande Rade) where high Hg concentrations were measured. These concentrations were higher than values reported in the current literature. This work reports the first assessment of Hg levels in edible organisms from the New Caledonian lagoon and the associated risk linked to their consumption by Human.
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