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Guidelines for biomonitoring persistent organic pollutants (POPs), using lichens and aquatic mosses – A review
2013
Augusto, Sofia | Máguas, Cristina | Branquinho, Cristina
During the last decades, awareness regarding persistent organic pollutants (POPs), such dioxins and furans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs), has become a cutting-edge topic, due to their toxicity, bioaccumulation and persistency in the environment. Monitoring of PCDD/Fs and PAHs in air and water has proven to be insufficient to capture deposition and effects of these compounds in the biota. To overcome this limitation, environmental biomonitoring using lichens and aquatic mosses, have aroused as promising tools. The main aim of this work is to provide a review of: i) factors that influence the interception and accumulation of POPs by lichens; ii) how lichens and aquatic bryophytes can be used to track different pollution sources and; iii) how can these biomonitors contribute to environmental health studies. This review will allow designing a set of guidelines to be followed when using biomonitors to assess environmental POP pollution.
Show more [+] Less [-]What is required for the validation of in vitro assays for predicting contaminant relative bioavailability? Considerations and criteria
2013
Juhasz, Albert L. | Basta, Nicholas T. | Smith, Euan
A number of studies have shown the potential of in vitro assays to predict contaminant in vivo relative bioavailability in order to refine human health exposure assessment. Although the term ‘validated’ has been used to describe the goodness of fit between in vivo and in vitro observations, its misuse has arisen from semantic considerations in addition to the lack of defined criteria for establishing performance validation. While several internal validation methods may be utilised, performance validation should preferably focus on assessing the agreement of model predictions with a set of data which are independent of those used to construct the model. In order to achieve robust validated predictive models, a number of parameters (e.g. size of data set, source of independent soils, contaminant concentration range, animal model, relative bioavailability endpoint) need to be considered in addition to defined criteria for establishing performance validation which are currently lacking.
Show more [+] Less [-]Bridging the gap between traffic generated health stressors in urban areas: Predicting xylene levels in EU cities
2013
Vlachokostas, Ch | Michailidou, A.V. | Spyridi, D. | Moussiopoulos, Ν
Many citizens live, work, commute, or visit traffic intensive spaces and are exposed to high levels of chemical health stressors. However, urban conurbations worldwide present monitoring “shortage” – due to economical and/or practical constraints – for toxic stressors such as xylene isomers, which can pose human health risks. This “shortage” may be covered by the establishment of associations between rarely monitored substances such as xylenes and more frequently monitored (i.e. benzene) or usually monitored (i.e. CO). Regression analysis is used and strong statistical relationships are detected. The adopted models are applied to EU cities and comparison between measurements and predictions depicts their representativeness. The analysis provides transferability insights in an effort to bridge the gap between traffic-related stressors. Strong associations between substances of the air pollution mixture may be influential to interpret the complexity of the causal chain, especially if a synergetic exposure assessment in traffic intensive spaces is considered.
Show more [+] Less [-]Nature and sources of particle associated polycyclic aromatic hydrocarbons (PAH) in the atmospheric environment of an urban area
2013
Callén, M.S. | López, J.M. | Iturmendi, A. | Mastral, A.M.
The total PAH associated to the airborne particulate matter (PM10) was apportioned by one receptor model based on positive matrix factorization (PMF) in an urban environment (Zaragoza city, Spain) during February 2010–January 2011. Four sources associated with coal combustion, gasoline, vehicular and stationary emissions were identified, allowing a good modelling of the total PAH (R2 = 0.99). A seasonal behaviour of the four factors was obtained with higher concentrations in the cold season. The NE direction was one of the predominant directions showing the negative impact of industrial parks, a paper factory and a highway located in that direction. Samples were classified according to hierarchical cluster analysis obtaining that, episodes with the most negative impact on human health (the highest lifetime cancer risk concentrations), were produced by a higher contribution of stationary and vehicular emissions in winter season favoured by high relative humidity, low temperature and low wind speed.
Show more [+] Less [-]Modeled PM2.5 removal by trees in ten U.S. cities and associated health effects
2013
Nowak, David J. | Hirabayashi, Satoshi | Bodine, Allison | Hoehn, Robert
Urban particulate air pollution is a serious health issue. Trees within cities can remove fine particles from the atmosphere and consequently improve air quality and human health. Tree effects on PM2.5 concentrations and human health are modeled for 10 U.S. cities. The total amount of PM2.5 removed annually by trees varied from 4.7 tonnes in Syracuse to 64.5 tonnes in Atlanta, with annual values varying from $1.1 million in Syracuse to $60.1 million in New York City. Most of these values were from the effects of reducing human mortality. Mortality reductions were typically around 1 person yr−1 per city, but were as high as 7.6 people yr−1 in New York City. Average annual percent air quality improvement ranged between 0.05% in San Francisco and 0.24% in Atlanta. Understanding the impact of urban trees on air quality can lead to improved urban forest management strategies to sustain human health in cities.
Show more [+] Less [-]Uptake and accumulation of four PPCP/EDCs in two leafy vegetables
2013
Dodgen, L.K. | Li, J. | Parker, D. | Gan, J.J.
Many pharmaceutical and personal care products (PPCPs) and endocrine-disrupting chemicals (EDCs) are present in reclaimed water, leading to concerns of human health risks from the consumption of food crops irrigated with reclaimed water. This study evaluated the potential for plant uptake and accumulation of four commonly occurring PPCP/EDCs, i.e., bisphenol A (BPA), diclofenac sodium (DCL), naproxen (NPX), and 4-nonylphenol (NP), by lettuce (Lactuca sativa) and collards (Brassica oleracea) in hydroponic culture, using 14C-labeled compounds. In both plant species, plant accumulation followed the order of BPA > NP > DCL > NPX and accumulation in roots was much greater than in leaves and stems. Concentrations of 14C-PPCP/EDCs in plant tissues ranged from 0.22 ± 0.03 to 927 ± 213 ng/g, but nearly all 14C-residue was non-extractable. PPCP/EDCs, particularly BPA and NP, were also extensively transformed in the nutrient solution. Dietary uptake of these PPCP/EDCs by humans was predicted to be negligible.
Show more [+] Less [-]Assessing urban habitat quality using spectral characteristics of Tilia leaves
2013
Khavanin Zadeh, A.R. | Veroustraete, F. | Buytaert, Jan | Dirckx, J. | Samson, R.
Monitoring environmental quality in urban areas is an important issue offering possibilities to control and improve urban habitat quality as well as to avoid adverse effects on human health. A tree leaf reflectance-based bio-monitoring method was used to assess the urban habitat quality of two contrasting habitat classes in the city of Gent (Belgium). As test trees, two Tilia species were selected. Custom made Matlab code is applied to process the measurements of leaf reflectance. This enables the discrimination between polluted and less polluted habitats. The results elicit, that leaf reflectance in the PAR range, as well as the NDAI (Normalised Difference Asymmetry index) are species dependent while Dorsiventral Leaf Reflectance Correlation (DLRC) seems to be independent of species. Therefore the assessment of urban habitat quality is perfectly feasible using leaf reflectance, when taking account of the species specificity of tree leaf physiological and structural responses to habitat quality.
Show more [+] Less [-]Developmental effects of aerosols and coal burning particles in zebrafish embryos
2013
Olivares, Alba | van Drooge, Barend L. | Casado, Marta | Prats, Eva | Serra, Montserrat | van der Ven, Leo T. | Kamstra, Jorke H. | Hamers, Timo | Hermsen, Sanne | Grimalt, Joan O. | Piña, Benjamin
Embryo toxicity of particles generated by combustion processes is of special concern for human health. A significant part of these toxic effects is linked to the binding of some pollutants (like polycyclic aromatic hydrocarbons or PAHs) to the Aryl hydrocarbon Receptor (AhR) and the activation of target genes, like the cytochrome P4501A. This activity was analyzed for ambient air and coal-combustion particle extracts in zebrafish embryos (the cyp1aDarT assay) and in two single-cell bioassays: the yeast-based YCM-RYA and the DR-luc (rat cells) assay. Observed AhR ligand activity of samples generally correlated to the predicted toxic effect according to their PAH composition, except for one of the coal combustion samples with an anomalously high activity in the cyp1aDarT assay. This sample induced deformities in zebrafish embryos. We concluded that the combination of morphological and molecular assays may detect embryonic toxic effects that cannot be predicted from chemical analyses or single-cell bioassays.
Show more [+] Less [-]Arsenic speciation in Chinese Herbal Medicines and human health implication for inorganic arsenic
2013
Liu, Xiao-Juan | Zhao, Quan-Li | Sun, Guo-Xin | Williams, Paul | Lu, Xiu-Jun | Cai, Jing-Zhu | Liu, Wen-Ju
Rice and drinking water are recognized as the dominant sources of arsenic (As) for human intake, while little is known about As accumulation and speciation in Chinese Herbal Medicines (CHMs), which have been available for many hundreds of years for the treatment of diseases in both eastern and western cultures. Inorganic arsenic was the predominant species in all of CHMs samples. The levels of inorganic arsenic in CHMs from fields and markets or pharmacies ranged from 63 to 550 ng/g with a mean of 208 ng/g and 94 to 8683 ng/g with a mean of 1092 ng/g, respectively. The highest concentration was found in the Chrysanthemum from pharmacies. It indicates that the risk of inorganic As in CHMs to human health is higher in medicines from markets or pharmacies than that collected directly from fields. Some CHMs may make a considerable contribution to the human intake of inorganic arsenic.
Show more [+] Less [-]Compliance of Royal Naval ships with nitrogen oxide emissions legislation
2013
Blatcher, D.J. | Eames, I.
Nitrogen oxide (NOx) emissions from marine diesel engines pose a hazard to human health and the environment. From 2021, demanding emissions limits are expected to be applied to sea areas that the Royal Navy (RN) accesses. We analyze how these future constraints affect the choice of NOx abatement systems for RN ships, which are subject to more design constraints than civilian ships. A weighted matrix approach is used to facilitate a quantitative assessment.For most warships to be built soon after 2021 Lean Nitrogen Traps (LNT) in conjunction with Exhaust Gas Recirculation (EGR) represents a relatively achievable option with fewer drawbacks than other system types. Urea-selective catalytic reduction is likely to be most appropriate for ships that are built to civilian standards. The future technologies that are at an early stage of development are discussed.
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