Emission database for global atmospheric research (Edgar)

Atmospheric chemistry and climate modellers require gridded global emissions data as input into their models. To meet this urgent need a global emissions source database called EDGAR is being developed by TNO and RIVM to estimate for 1990, on a regional and on a grid basis, annual emissions of greenhouse gases (CO₂, CH₄, N₂O, CO, NO_x, non-methane VOC, SO_x), of NH₃, and of ozone depleting compounds (halocarbons) from all known sources. The aim is to establish at due levels of spatial, temporal and source aggregation the emissions from both anthropogenic and biogenic sources: a complete set of data required to estimate the total source strength of the various gases with a 1×1 ° resolution (altitude resolution of 1 km) and a temporal resolution of a month, supplemented by diurnal variation, as agreed upon in the Global Emissions Inventory Activity (GEIA) of the International Atmospheric Chemistry Programme (IGAC). In this way EDGAR will meet the requirements of present and future developments in the field of atmospheric modelling. The data comprise demographic data, social and economic factors, land use distributions and emission factors (with due emphasis on the uncertainty). As understanding in this field is still changing, due attention is paid to flexibility regarding the disaggregation of sources, spatial and temporal resolution and species. The objective and methodology chosen for the construction of the database and the structural design of the database system are presented, as well as the type and sources of data and the approach used for data collection. As an example, the construction of the N₂O inventory is discussed.     

Mercury speciation in plankton from the Cabo Frio Bay,SE - Brazil

Mercury (Hg) is considered a global pollutant, and the scientific community has shown great concern about its toxicity as it may affect the biota of entire systems, through bioaccumulation and bioamplification processes of its organic form, methylmercury (MeHg), along food web. However, few research studies deal with bioaccumulation of Hg from marine primary producers and the first-order consumers. So, this study aims to determine Hg distribution and concentration levels in phytoplankton and zooplankton in the Cabo Frio Bay, Brazil, a site influenced by coastal upwelling. The results from Hg speciation analyses show that inorganic mercury Hg(II) was the predominant specie in plankton from this bay. The annual Hg species distribution in plankton shown mean concentration of 2.00?±?1.28 ng Hg(II)?g^?1 and 0.15?±?0.08 ng MeHg g^?1 wet weight (phytoplankton) and 2.5?±?2.03 ng Hg(II)?g^?1 and 0.25?±?0.09 ng MeHg g^?1 wet weight (zooplankton). Therefore, upwelling zones should be considered in the Hg biogeochemical cycle models as a process that enhances Hg(II) bioaccumulation in plankton, raising its bioavailability and shelf deposition.     

Hare or Tortoise? Trade-offs in Recovering Sustainable Bioeconomic Systems

In this paper, we develop a framework for (a) the study of sustainability of dynamic bioeconomic systems and (b) the definition of recovery paths from unsustainable situations. We assume that the system follows a sustainable trajectory if it evolves over time within a set of multidimensional constraints. We use the mathematical concept of viability to characterize sustainability. Recovery paths are studied with regards to their duration and their acceptability. This general framework is applied to the issue of recovering sustainable fisheries. We define sustainability in a fishery as the requirement that a set of economic, ecological, and social constraints is satisfied at all times. Recovery paths are characterized by the time required to obtain sustainable exploitation conditions in the fishery and by the acceptable recovery costs for fishermen. In particular, we identify the recovery path which minimizes the time of crisis under a minimum transition profit constraint. We then describe the trade-off between speed and accepted costs of recovery paths, by comparing “Hare”-like high-speed–high-cost strategies to “Tortoise”-like low-speed–low-cost strategies. We illustrate our results by means of a numerical analysis of the Bay of Biscay Nephrops fishery.     

Detection of fungal development in closed spaces through the determination of specific chemical targets

In addition to the biodegradation problems encountered in buildings, exposure of their occupants to moulds is responsible for numerous diseases: infections (invasive nosocomial aspergillosis), immediate or delayed allergies, food-borne infections and different types of irritation. In this context, the aim of our work has been to determine specific chemical tracers for fungal development on construction materials. More generally, by detecting a specific chemical fingerprint of fungal development, our objective was to propose a microbiological alert system which could control systems and/or procedures for the microbiological treatment of indoor areas.

We therefore characterized the chemical emissions from six types of construction material contaminated artificially by moulds. Chemical fingerprints were established for 19 compounds arising specifically from fungal metabolism: 2-ethylhexanoic acid methyl ester, 1-octen-3-ol, 3-heptanol, 3-methyl-1-butanol, 2-methyl-1-butanol, 1,3-octadiene, 2-(5H)-furanone, 2-heptene, -pinene, 2-methylisoborneol, 4-heptanone, 2-methylfuran, 3-methylfuran, dimethyldisulfide, methoxybenzene, a terpenoid and three sesquiterpenes.

Determining the origin of these compounds and their specific links with a growth substrate or fungal species made it possible to judge the pertinence of choosing these compounds as tracers.

Thus the detecting specific volatile organic compounds emitted as from the second day of fungal growth demonstrated that this approach had the advantage of detecting fungal development both reliably and rapidly before any visible signs of contamination could be detected.     

Methylmercury speciation in the dissolved phase of a stratified lake using the diffusive gradient in thin film technique

The diffusive gradient in thin film (DGT) technique was successfully used to monitor methylmercury (MeHg) speciation in the dissolved phase of a stratified boreal lake, Lake 658 of the Experimental Lakes Area (ELA) in Ontario, Canada. Water samples were conventionally analysed for MeHg, sulfides, and dissolved organic matter (DOM). MeHg accumulated by DGT devices was compared to MeHg concentration measured conventionally in water samples to establish MeHg speciation. In the epilimnion, MeHg was almost entirely bound to DOM. In the top of the hypolimnion an additional labile fraction was identified, and at the bottom of the lake a significant fraction of MeHg was potentially associated to colloidal material. As part of the METAALICUS project, isotope enriched inorganic mercury was applied to Lake 658 and its watershed for several years to establish the relationship between atmospheric Hg deposition and Hg in fish. Little or no difference in MeHg speciation in the dissolved phase was detected between ambient and spike MeHg.     

A flexible matrix algebra framework for the multimedia multipathway modeling of emission to impacts

When assessing human health or ecosystem impacts of chemicals several calculation steps need to be addressed. Matrix algebra solving techniques are a useful approach to structure and solve the system of mass balance equations assessing chemical fate in environmental multimedia models. We suggest expanding this matrix approach towards a framework which includes the exposure, effect, and damage assessment for human health and ecosystems, also applicable to spatial modeling. Special emphasis is laid upon interpretation of the physical meaning of different elements within the matrices. The proposed framework provides several advantages such as simplified updating or extending of models to new impact pathways, possibility of covering various models within the same framework and transparency. Interpretation of intermediate and final results is facilitated, e.g., allowing for direct identification of dominating exposure pathways. Model comparability and evaluation is well supported, as the four matrices contain all intermediate results in a clear and interpretable way, independent from parameters, such as amount and place of emission. Multidisciplinary work is strongly facilitated enabling the linkage of different models from various disciplines together, since each of its modules defines a clear interface of intermediate results. This framework was reviewed by an independent expert panel within a UNEP/SETAC workshop, and adopted as starting-point for new advances in modeling environmental toxic releases within the UNEP/SETAC Life Cycle Initiative.     

First-trimester diagnosis of osteogenesis imperfecta associated with encephalocele by conventional and three-dimensional ultrasound

To illustrate the three-dimensional sonographic features of a rare genetic disorder, we report on prenatal diagnosis of osteogenesis imperfecta congenita associated with encephalocele at 13 weeks of gestation, using conventional and three-dimensional ultrasound. Because the parents were first-degree cousins and on the basis of the family history, a recessive autosomal inheritance was suspected. Of seven previous pregnancies, five were unaffected and two had been terminated in the second trimester owing to a similar abnormality (one affected boy and one affected girl). In the case we present, the diagnosis was made on the basis of two-dimensional ultrasound performed by physicians aware of the history; the quality of three-dimensional ultrasound imaging suggests that this technique might have contributed toward establishing a precise diagnosis in the absence of a positive family history. Besides, the global view provided by three-dimensional surface-rendering images made the parents more confident of the accuracy of the diagnosis. Although osteogenesis imperfecta congenita is generally considered as autosomal dominant, the case we report suggests that it may be inherited in a recessive autosomal fashion at least when associated with encephalocele. Three-dimensional ultrasound confirmed the conventional two-dimensional examination and was helpful in convincing the parents of the accuracy of the diagnosis. Copyright © 2003 John Wiley & Sons, Ltd.     

Prenatal diagnosis and outcome of congenital splenic cyst: report of two cases

Congenital splenic cyst (CSC) is a rare condition, and only a few cases with prenatal diagnosis and no associated malformation have been reported. Spontaneous regression is possible in case of mild CSC (under 40 mm), but enlargement or secondary complications may lead to surgical treatment. We report, herein, two cases of isolated mild CSC with complete spontaneous postnatal regression. Copyright © 2006 John Wiley & Sons, Ltd.     

Is fetal gender a risk factor for severe congenital cytomegalovirus infection?

Cytomegalovirus is the main cause of congenital viral infection and amniotic fluid viral load appears to be the single nonclinical prognostic factor. However, as in other infectious diseases, host genetics may influence the severity of the disease. To test this hypothesis, we looked retrospectively at the fetal gender in cases of severe congenital cytomegalovirus infection in our database. We also analyzed the international English literature covering this subject between 1985 and 2003. The proportion of females with brain abnormalities was statistically different from that of males (62/258: 24% vs 30/251: 12%, p = 0.004). The risk of abnormal brain development in infected fetuses was twice as high in females than in males (Chi² = 8.7; OR = 2, IC [1.26–3.21]). In our cases, amniotic fluid CMV DNA load was not significantly higher in males than in females (p = 0.06) and was also similar in severely and non-severely infected fetuses (p = 0.09). Copyright © 2005 John Wiley & Sons, Ltd.