δ 13C and δ 15N variations in organic matter pools, Mytilus spp. and Macoma balthica along the European Atlantic coast

Stable carbon (δ ¹³C) and nitrogen (δ ¹⁵N) isotope (SI) values of sedimentary organic matter (SOM), seston and two dominant bivalves, Mytilus spp. and Macoma balthica, were studied at 18 stations along the European coast in spring and autumn 2004. Three main regions, the Baltic Sea (BS), the North Sea and English Channel (NS), and the Bay of Biscay (BB), were tested for possible geographic (latitudinal) differences in the SI values. In spring, only BS showed lower δ ¹³C values of seston and Mytilus spp., and higher δ ¹⁵N values of SOM, than NS and BB. No significant differences between the 3 regions were found in autumn. Irrespective of season and regions, Mytilus spp. was more ¹³C-depleted than M. balthica. δ ¹³C values of M. balthica, but not those of Mytilus spp., were significantly correlated with SOM. These results are consistent with differences in feeding behavior of Mytilus spp. and M. balthica, as the two species are known as obligatory-suspension and facultative-deposit feeders, respectively. In contrast, no differences in the δ ¹⁵N values of Mytilus spp. and M. balthica were found at individual stations, indicating the same trophic level of the two bivalves within the food webs. At some stations, irrespective of geographic location, both bivalves showed δ ¹⁵N values up to 18–20 ‰. These were two trophic levels higher than those found at the other stations, indicating local and/or episodic eutrophic conditions, probably due to waste water discharge, and the effectiveness of both Mytilus spp. and M. balthica as bio-indicators of anthropogenic eutrophication. Overall, our results suggest that pathways of energy flow from OM pools to dominant bivalves is more related to local environmental conditions than to geographic regions across the European coastline. This has implications for food web studies along the Atlantic coast because most of the values are consistent over a large area and show no significant differences. Therefore, the present study can be used twofold for the determination of trophic baselines and for the correction of the trophic position of consumers higher up in the food web in the case of differences in waste water discharge.     

Impact of “Designated Smoking Area” Policy on Nicotine Vapor and Particle Concentrations in a Modern Office Building

A series of measurements of nicotine vapor and particle concentrations were carried out in a modern office building. The measurement program was designed to document the impact of the new smoking policy (e.g. smoking restricted to two specific areas) on air quality in various parts of the building.

Measurements at over 30 locations examined areas where smoking was restricted, where smoking was permitted, and where an air handler shared the load of a designated smoking area. These measurements were taken at the same locations before and after the policy was Implemented.

The measurement results Indicated that: ? After the policy was implemented, general employee exposure to nicotine vapor (as a surrogate for all environmental tobacco smoke) was reduced by about 98 percent on most floors. Other patterns related to spillover from designated smoking areas and changes in the designated smoking areas themselves are described in the paper.

? Substantial reductions in exposure to nicotine vapor were found even for those general office areas which had the highest concentrations after the policy was implemented.

     

Summary of the Federal Emissions Trading Policy Statement

This paper is directed to those concerned with using emissions trading to achieve greater flexibility and reduce the costs of complying with air pollution emission standards.     

Correction to: Municipal wastewater viral pollution in Saudi Arabia: effect of hot climate on COVID-19 disease spreading

Environmental Science and Pollution Research -     

A mass transfer model of ammonia volatilisation from anaerobic digestate

Anaerobic digestion (AD) is becoming increasingly popular for treating organic waste. The methane produced can be burned to generate electricity and the digestate, which is high in mineral nitrogen, can be used as a fertiliser. In this paper we evaluate potential losses of ammonia via volatilisation from food waste anaerobic digestate using a closed chamber system equipped with a sulphuric acid trap. Ammonia losses represent a pollution source and, over long periods could reduce the agronomic value of the digestate. Observed ammonia losses from the experimental system were linear with time. A simple non-steady-state partitioning model was developed to represent the process. After calibration, the model was able to describe the behaviour of ammonia in the digestate and in the trap very well. The average rate of volatilisation was approximately 5.2 g N m^?2 week^?1. The model was used to extrapolate the findings of the laboratory study to a number of AD storage scenarios. The simulations highlight that open storage of digestate could result in significant losses of ammonia to the atmosphere. Losses are predicted to be relatively minor from covered facilities, particularly if depth to surface area ratio is high.     

Molecular Transport of Xylene Through Palm Pressed Fibre Filled Low Density Polyethylene: Role of Fibre Content,Alkali Treatment and Particle Size

We report in this paper the transport of an aromatic solvent, xylene through palm pressed fibre filled low density polyethylene composites studied at three different temperatures (40, 60, and 80 °C) by conventional weight-gain method. The diffusion parameters were investigated with special reference to the effect of fibre content, temperature and particle size. The effect of alkali treatment on solvent uptake was also analyzed. The transport coefficients of diffusion, permeation and sorption were determined to evaluate the influence of interface bonding on transport properties. The van’t Hoff relationship was used to determine the thermodynamic parameters and was found that the estimated free energies of sorption were all positive, indicating non-spontaneity of the solubility of PPF/LDPE composites. The first order kinetic rate constant and swelling parameters were also evaluated.     

Early detection of fetal cardiac abnormalities: how effective is it and how should we manage these patients?

Congenital heart defects (CHDs), the most commonly occurring congenital malformations, cause significant mortality and morbidity. With the recognition of early markers for CHD and the development of better ultrasound resolution, interest has turned toward performing a screening anomaly scan, including the heart, together with the nuchal scan. It is also possible, with adequate skill and training, to competently perform an echocardiogram <16 weeks' gestation. This article reviews the detection of major CHD in the first trimester and early second trimester including specific markers that help to identify high-risk groups for early fetal echocardiography (EFEC). CHD detection during first-trimester screening is low (2.3–56%) depending on the center's experience and the population studied. An increased nuchal translucency, abnormal ductus venosus flow, and tricuspid regurgitation in the first trimester are associated with an increased CHD risk and can be used together to identify high-risk fetuses for EFEC. EFEC requires skilled scanning and the expertise of a fetal echocardiographer. In high-risk populations, it is 78.5% sensitive with a 74.5% concordance between the EFEC and the mid-gestational echocardiogram. The availability of qualified personnel and diagnostic accuracy are prerequisites before EFEC can be introduced into management protocols. The limitations of EFEC should be recognized, and a later confirmatory echocardiogram is recommended. © 2014 John Wiley & Sons, Ltd.     

Impacts of “metals” on human health: a comparison between nine different methodologies for Life Cycle Impact Assessment (LCIA)

This paper looks into the differences and uncertainties in determining the impact of “metals’” emissions on human health, in Life Cycle Impact Assessment (LCIA). Metals are diverse substances, with different properties and characteristics, considered important in LCIA because of their toxicity to humans and ecosystems. First, we defined a list of the most significant metals in terms of impacts on human health. This was done according to precise criteria accounting for both physical and toxic properties of the metals. Second, we performed an LCIA on different key processes using various existing LCIA methodologies and including also USEtox: the recently developed consensus-model for LCIA. Last, we compared the results in relative terms using a contribution analysis. The analysis showed poor or no agreement between the methods: the relative contribution of each metal and of the metals in total to the total impact on human health changes greatly according to the LCIA method used. These differences are due mainly to the number of metals included in each method and to the technique used to calculate the characterization factors. Results obtained with USEtox show no apparent correlation with results calculated with other methods. At present time USEtox is recommended as the best model for LCIA on human toxicity, but mainly because of the large consensus behind it, because its uncertainties regarding metals are still high. The study gives a good and simple overview regarding the way different methods address the impact assessment for metals, and helps in the interpretation of LCIA results for actual LCA studies where metal emissions are involved.     

Toxicity potentials from waste cellular phones,and a waste management policy integrating consumer,corporate, and government responsibilities

Cellular phones have high environmental impact potentials because of their heavy metal content and current consumer attitudes toward purchasing new phones with higher functionality and neglecting to return waste phones into proper take-back systems. This study evaluates human health and ecological toxicity potentials from waste cellular phones; highlights consumer, corporate, and government responsibilities for effective waste management; and identifies key elements needed for an effective waste management strategy. The toxicity potentials are evaluated by using heavy metal content, respective characterization factors, and a pathway and impact model for heavy metals that considers end-of-life disposal in landfills or by incineration. Cancer potentials derive primarily from Pb and As; non-cancer potentials primarily from Cu and Pb; and ecotoxicity potentials primarily from Cu and Hg. These results are not completely in agreement with previous work in which leachability thresholds were the metric used to establish priority, thereby indicating the need for multiple or revised metrics. The triple bottom line of consumer, corporate, and government responsibilities is emphasized in terms of consumer attitudes, design for environment (DfE), and establishment and implementation of waste management systems including recycling streams, respectively. The key strategic elements for effective waste management include environmental taxation and a deposit-refund system to motivate consumer responsibility, which is linked and integrated with corporate and government responsibilities. The results of this study can contribute to DfE and waste management policy for cellular phones.