Alphafetoprotein,cholinesterases and rapidly adhering cells in the prenatal diagnosis of neural tube defects

Amniotic fluid cholinesterases tested on polyacrylamide gel and rapidly adhering cell analysis were compared in their efficiency at diagnosing fetal neural tube defects in three cases where the alphafetoprotein results were equivocal. While rapidly adhering cells were also equivocal, the cholinesterases consistently gave a clear indication of fetal abnormality.     

Impact of a proposed revision of the IESTI equation on the acute risk assessment conducted when setting maximum residue levels (MRLs) in the European Union (EU): A case study

ABSTRACT

Proposals to update the methodology for the international estimated short-term intake (IESTI) equations were made during an international workshop held in Geneva in 2015. Changes to several parameters of the current four IESTI equations (cases 1, 2a, 2b, and 3) were proposed. In this study, the overall impact of these proposed changes on estimates of short-term exposure was studied using the large portion data available in the European Food Safety Authority PRIMo model and the residue data submitted in the framework of the European Maximum Residue Levels (MRL) review under Article 12 of Regulation (EC) No 396/2005. Evaluation of consumer exposure using the current and proposed equations resulted in substantial differences in the exposure estimates; however, there were no significant changes regarding the number of accepted MRLs. For the different IESTI cases, the median ratio of the new versus the current equation is 1.1 for case 1, 1.4 for case 2a, 0.75 for case 2b, and 1 for case 3. The impact, expressed as a shift in the IESTI distribution profile, indicated that the 95th percentile IESTI shifted from 50% of the acute reference dose (ARfD) with the current equations to 65% of the ARfD with the proposed equations. This IESTI increase resulted in the loss of 1.2% of the MRLs (37 out of 3110) tested within this study. At the same time, the proposed equations would have allowed 0.4% of the MRLs (14 out of 3110) that were rejected with the current equations to be accepted. The commodity groups that were most impacted by these modifications are solanacea (e.g., potato, eggplant), lettuces, pulses (dry), leafy brassica (e.g., kale, Chinese cabbage), and pome fruits. The active substances that were most affected were fluazifop-p-butyl, deltamethrin, and lambda-cyhalothrin.     

Predictions of U.K. regulated power station contributions to regional air pollution and deposition: a model comparison exercise

Contributions of the emissions from a U.K. regulated fossil-fuel power station to regional air pollution and deposition are estimated using four air quality modeling systems for the year 2003. The modeling systems vary in complexity and emphasis in the way they treat atmospheric and chemical processes, and include the Community Multiscale Air Quality (CMAQ) modeling system in its versions 4.6 and 4.7, a nested modeling system that combines long- and short-range impacts (referred to as TRACK-ADMS [Trajectory Model with Atmospheric Chemical Kinetics-Atmospheric Dispersion Modelling System]), and the Fine Resolution Atmospheric Multi-pollutant Exchange (FRAME) model. An evaluation of the baseline calculations against U.K. monitoring network data is performed. The CMAQ modeling system version 4.6 data set is selected as the reference data set for the model footprint comparison. The annual mean air concentration and total deposition footprints are summarized for each modeling system. The footprints of the power station emissions can account for a significant fraction of the local impacts for some species (e.g., more than 50% for SO2 air concentration and non-sea-salt sulfur deposition close to the source) for 2003. The spatial correlation and the coefficient of variation of the root mean square error (CVRMSE) are calculated between each model footprint and that calculated by the CMAQ modeling system version 4.6. The correlation coefficient quantifies model agreement in terms of spatial patterns, and the CVRMSE measures the magnitude of the difference between model footprints. Possible reasons for the differences between model results are discussed. Finally, implications and recommendations for the regulatory assessment of the impact of major industrial sources using regional air quality modeling systems are discussed in the light of results from this case study.     

Evaluation of a CMAQ simulation at high resolution over the UK for the calendar year 2003

A comprehensive ‘operational’ evaluation of the performance of the Community Multiscale Air Quality (CMAQ) modelling system version 4.6 was conducted in support of pollution assessment in the UK for the calendar year 2003. The model was run on multiple grids using one-way nests down to a horizontal resolution as fine as 5 km over the whole of the UK. The model performance was evaluated for pollutants with standards and limit values (e.g. O₃, PM₁₀) and species contributing to acidic and nitrogenous deposition (e.g. NH₃, SO₄^2–, NO₃^–, NH₄⁺) against data from operational national monitoring networks. The key performance characteristics of the modelling system were found to be variable according to acceptance criteria and to depend on the type (e.g. urban, rural) and location of the sites, as well as on the time of the year. As regards the techniques that were used for ‘operational’ evaluation, performance generally complied with expected levels and ranged from good (e.g. O₃, SO₄^2–) to moderate (e.g. PM₁₀, NO₃^–). At a few sites low correlations and large standard deviations for some species (e.g. SO₂) suggest that these sites are subject to local factors (e.g. topography, emission sources) that are not well described in the model. Overall, the model tends to over predict O₃ and under predict aerosol species (except SO₄^2–). Discrepancies between predicted and observed concentrations may be due to a variety of intertwined factors, which include inaccuracies in meteorological predictions, chemical boundary conditions, temporal variability in emissions, and uncertainties in the treatment of gas and aerosol chemistry. Further work is thus required to investigate the respective contributions of such factors on the predicted concentrations.     

Use of embodied energy and ecological footprinting to assess the global environmental impact of consumption in an Irish city-region

The objective of this paper is to compare the carbon emissions produced as a result of product consumption by the residents of an Irish city-region, that is Limerick City and its environs. The resulting carbon footprints are used to compare imports of food items, manufactured products and construction materials with domestic production as well as changes between 1996 and 2002. The total ecological footprints (EF) associated with product consumption are also calculated by aggregating the theoretical land required to sequester carbon emissions and the terrestrial land area appropriated for agricultural production and industrial activity. It is suggested that this approach be used to allocate producer or consumer responsibility for environmental impacts from trade.     

Water-soluble fractions of composts for the photodegradation of organic pollutants in solar light

Composts fractions were extracted by water from composts at the beginning and at the end of the composting process. These water extracts were characterized by elementary analysis and spectroscopies, and then, tested for their capacity to photosensitize the degradation of three aromatic compounds: Irgarol, fenuron, and 2,4,6-trimethylphenol. In solar light, the water extracts (25 mg/l) were found to completely degrade 2,4,6-trimethylphenol after 24 h, and afford a transformation of fenuron and Irgarol of 25% and 18%, respectively.An erratum to this article can be found at     

Municipal solid waste management in Africa: strategies and livelihoods in Yaoundé, Cameroon

This paper provides an overview of the state of municipal solid waste (MSW) management in the capital of Cameroon, Yaoundé, and suggests some possible solutions for its improvement. The institutional, financial, and physical aspects of MSW management, as well as the livelihoods of the population, were analyzed. Our study revealed that distances and lack of infrastructure have a major impact on waste collection. Garbage bins are systematically mentioned as the primary infrastructure needed by the population in all quarters, whether it be a high or low standard community. The construction of transfer stations and the installation of garbage bins are suggested as a solution to reduce distances between households and garbage bins, thus improving waste collection vehicle accessibility. Transfer stations and garbage bins would enable the official waste collection company to expand its range of services and significantly improve waste collection rates. Several transfer stations have already been set up by non-governmental organizations (NGOs) and community-based organizations (CBOs), but they require technical, institutional and funding support. Research is needed on the quality and safety of community-made compost, as well as on soil fertility in urban and peri-urban areas. Most of the stakeholders, municipalities, the official waste collection company and households acknowledge the need for better monitoring and regulation of MSW management. The urban community of Yaoundé also needs to maintain its support of MSW management and promote the sustainability of NGOs and CBOs operating in underserved areas not yet covered by adequate infrastructures. A major opportunity for implementation of such waste policy is the heavily indebted poor countries (HIPC) program dedicated to urban planning and good governance.     

Prenatal screening for haemoglobin disorders

The technology has been available to detect carriers of haemoglobin disorders since the late 1960s. Prenatal diagnosis has been available since 1978. First trimester diagnosis by chorionic villus sampling and DNA analysis was introduced in 1982, and subsequent simplifications in DNA technology have made screening, counselling and prenatal diagnosis cost-effective at the community level, in countries at all levels of development. Audit of prenatal diagnosis for haemoglobin disorders in countries which have the resources and infrastructure necessary for genetic population screening (such as the UK and other European countries), has shown that the number of prenatal diagnoses actually performed fall far short of expectation. The demonstration that this reflects failures in delivering information, screening and counselling to the populations at risk, rather than rejection of prenatal diagnosis, shows the importance of placing more emphasis on the organisational and social requirements for genetic population screening. In some countries current attitudes towards abortion exclude provision of prenatal diagnosis within the health service, but in many such cases it has been set up in the private sector. It is also being introduced through combined private and charitable efforts in an increasing number of developing countries, including some with extremely limited health resources: such centres are likely to act as nuclei for emergence of genetics services in these communities. A particularly notable recent achievement is the introduction of prenatal diagnosis in Nigeria, where 1–2% of all children born suffer from sickling disorders.