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Chronic bisphenol A exposure alters behaviors of zebrafish (Danio rerio)
2015
Wang, Ju | Wang, Xia | Xiong, Can | Liu, Jian | Hu, Bing | Zheng, Lei
The adult zebrafish (Danio rerio) were exposed to treated-effluent concentration of bisphenol A (BPA) or 17β-estradiol (E2) for 6 months to evaluate their effects on behavioral characteristics: motor behavior, aggression, group preference, novel tank test and light/dark preference. E2 exposure evidently dampened fish locomotor activity, while BPA exposure had no marked effect. Interestingly, BPA-exposed fish reduced their aggressive behavior compared with control or E2. Both BPA and E2 exposure induced a significant decrease in group preference, as well as a weaker adaptability to new environment, exhibiting lower latency to reach the top, more entries to the top, longer time spent in the top, fewer frequent freezing, and fewer erratic movements. Furthermore, the circadian rhythmicity of light/dark preference was altered by either BPA or E2 exposure. Our results suggest that chronic exposure of treated-effluent concentration BPA or E2 induced various behavioral anomalies in adult fish and enhanced ecological risk to wildlife.
Mostrar más [+] Menos [-]Pharmaceuticals and personal care products alter the holobiome and development of a medically important mosquito
2015
Pennington, Marcus J. | Rivas, Nicholas G. | Prager, Sean M. | Walton, William E. | Trumble, John T.
The increasing demand for fresh water has forced many countries to use reclaimed wastewater for agricultural purposes. This water contains pharmaceuticals and personal care products (PPCPs) that remain biologically active following passage through wastewater treatment plants. Run-off from farms and contaminated water from treatment facilities exposes aquatic ecosystems to PPCPs. This study examined the effects of PPCPs on a lower trophic organism. Culex quinquefasciatus larvae were reared in water contaminated with environmentally relevant concentrations of common PPCPs. Acetaminophen alone and a mixture of contaminants were found to increase developmental time of larvae. Susceptibility to Bti increased in larvae exposed to antibiotics, acetaminophen, or a mixture of PPCPs. Antibiotics, hormones, and the mixture altered the mosquito bacterial microbiome. Overall, the results indicate that at environmentally relevant concentrations, PPCPs in reclaimed water can have biologically important effects on an ecologically and medically important lower trophic level insect.
Mostrar más [+] Menos [-]Effects of environmental cadmium and lead exposure on adults neighboring a discharge: Evidences of adverse health effects
2015
Cabral, Mathilde | Touré, Aminata | Garçon, Guillaume | Diop, Cheikh | Bouhsina, Saâd | Dewaele, Dorothée | Cazier, Fabrice | Courcot, Dominique | Tall-Dia, Anta | Shirali, Pirouz | Diouf, Amadou | Fall, Mamadou | Verdin, Anthony
The purpose of the study was to determine Pb and Cd concentrations in humans and to assess the effect of co-exposure to these metals on biomarkers of oxidative stress and nephrotoxicity. Blood and urine levels of Pb and Cd, oxidative stress and urinary renal biomarkers were measured in 77 subjects neighboring a discharge and 52 in the control site. Exposed subjects showed significantly higher levels of lead and cadmium in blood and urine than the controls. Excessive production of reactive oxygen species induced by these metals in exposed subjects conducted to a decrease in antioxidant defense system (GPx, Selenium, GSH) and an increase in lipid peroxidation (MDA). Moreover, changes in markers of nephrotoxicity (high urinary concentrations of total protein, RBP and CC16, as well as GSTα and LDH increased activities) suggested the occurrence of discrete and early signs of impaired renal function for the discharge neighboring population.
Mostrar más [+] Menos [-]Problems in the fingerprints based polycyclic aromatic hydrocarbons source apportionment analysis and a practical solution
2015
Zou, Yonghong | Wang, Lixia | Christensen, Erik R.
This work intended to explain the challenges of the fingerprints based source apportionment method for polycyclic aromatic hydrocarbons (PAH) in the aquatic environment, and to illustrate a practical and robust solution. The PAH data detected in the sediment cores from the Illinois River provide the basis of this study. Principal component analysis (PCA) separates PAH compounds into two groups reflecting their possible airborne transport patterns; but it is not able to suggest specific sources. Not all positive matrix factorization (PMF) determined sources are distinguishable due to the variability of source fingerprints. However, they constitute useful suggestions for inputs for a Bayesian chemical mass balance (CMB) analysis. The Bayesian CMB analysis takes into account the measurement errors as well as the variations of source fingerprints, and provides a credible source apportionment. Major PAH sources for Illinois River sediments are traffic (35%), coke oven (24%), coal combustion (18%), and wood combustion (14%).
Mostrar más [+] Menos [-]Effect of humic acid (HA) on sulfonamide sorption by biochars
2015
Lian, Fei | Sun, Binbin | Chen, Xi | Zhu, Lingyan | Liu, Zhongqi | Xing, Baoshan
Effect of quantity and fractionation of loaded humic acid (HA) on biochar sorption for sulfonamides was investigated. The HA was applied in two different modes, i.e. pre-coating and co-introduction with sorbate. In pre-coating mode, the polar fractions of HA tended to interact with low-temperature biochars via H-bonding, while the hydrophobic fractions were likely to be adsorbed by high-temperature biochars through hydrophobic and π-π interactions, leading to different composition and structure of the HA adlayers. The influences of HA fractionation on biochar sorption for sulfonamides varied significantly, depending on the nature of interaction between HA fraction and sorbate. Meanwhile, co-introduction of HA with sulfonamides revealed that the effect of HA on sulfonamide sorption was also dependent on HA concentration. These findings suggest that the amount and fractionation of adsorbed HA are tailored by the surface properties of underlying biochars, which differently affect the sorption for organic contaminants.
Mostrar más [+] Menos [-]Pollutants bioavailability and toxicological risk from microplastics to marine mussels
2015
Avio, Carlo Giacomo | Gorbi, Stefania | Milan, Massimo | Benedetti, Maura | Fattorini, Daniele | D'Errico, Giuseppe | Pauletto, Marianna | Bargelloni, Luca | Regoli, Francesco
Microplastics represent a growing environmental concern for the oceans due to their potential of adsorbing chemical pollutants, thus representing a still unexplored source of exposure for aquatic organisms. In this study polyethylene (PE) and polystyrene (PS) microplastics were shown to adsorb pyrene with a time and dose-dependent relationship. Results also indicated a marked capability of contaminated microplastics to transfer this model PAH to exposed mussels Mytilus galloprovincialis; tissue localization of microplastics occurred in haemolymph, gills and especially digestive tissues where a marked accumulation of pyrene was also observed. Cellular effects included alterations of immunological responses, lysosomal compartment, peroxisomal proliferation, antioxidant system, neurotoxic effects, onset of genotoxicity; changes in gene expression profile was also demonstrated through a new DNA microarray platform. The study provided the evidence that microplastics adsorb PAHs, emphasizing an elevated bioavailability of these chemicals after the ingestion, and the toxicological implications due to responsiveness of several molecular and cellular pathways to microplastics.
Mostrar más [+] Menos [-]Characterising the exchangeability of phenanthrene associated with naturally occurring soil colloids using an isotopic dilution technique
2015
Tavakkoli, Ehsan | Juhasz, Albert | Donner, Erica | Lombi, Enzo
The association of polycyclic aromatic hydrocarbons (PAHs) with inorganic and organic colloids is an important factor influencing their bioavailability, mobility and degradation in the environment. Despite this, our understanding of the exchangeability and potential bioavailability of PAHs associated with colloids is limited. The objective of this study was to use phenanthrene as a model PAH compound and develop a technique using 14C phenanthrene to quantify the isotopically exchangeable and non-exchangeable forms of phenanthrene in filtered soil water or sodium tetraborate extracts. The study was also designed to investigate the exchangeability of colloidal phenanthrene as a function of particle size. Our findings suggest that the exchangeability of phenanthrene in sodium tetraborate is controlled by both inorganic and organic colloids, while in aqueous solutions inorganic colloids play the dominant role (even though coating of these by organic matter cannot be excluded). Filter pore size did not have a significant effect on phenanthrene exchangeability.
Mostrar más [+] Menos [-]Assessment and mitigation of the environmental burdens to air from land applied food-based digestate
2015
Tiwary, A. | Williams, I.D. | Pant, D.C. | Kishore, V.V.N.
Anaerobic digestion (AD) of putrescible urban waste for energy recovery has seen rapid growth over recent years. In order to ascertain its systems scale sustainability, however, determination of the environmental fate of the large volume of digestate generated during the process is indispensable. This paper evaluates the environmental burdens to air associated with land applied food-based digestate in terms of primary pollutants (ammonia, nitrogen dioxide) and greenhouse gases (methane and nitrous oxide). The assessments have been made in two stages – first, the emissions from surface application of food-based digestate are quantified for the business as usual (BAU). In the next step, environmental burden minimisation potentials for the following three mitigation measures are estimated – mixed waste digestate (MWD), soil-incorporated digestate (SID), and post-methanated digestate (PMD). Overall, the mitigation scenarios demonstrated considerable NH3, CH4 and N2O burden minimisation potentials, with positive implications for both climate change and urban pollution.
Mostrar más [+] Menos [-]Influence of avenue-trees on air quality at the urban neighborhood scale. Part I: Quality assurance studies and turbulent Schmidt number analysis for RANS CFD simulations
2015
Gromke, Christof | Blocken, Bert
Flow and dispersion of traffic pollutants in a generic urban neighborhood with avenue-trees were investigated with Computational Fluid Dynamics (CFD). In Part I of this two-part contribution, quality assessment and assurance for CFD simulations in urban and vegetation configurations were addressed, before in Part II flow and dispersion in a generic urban neighborhood with multiple layouts of avenue-trees were studied. In a first step, a grid sensitivity study was performed that inferred that a cell count of 20 per building height and 12 per canyon width is sufficient for reasonable grid insensitive solutions. Next, the performance of the realizable k-ε turbulence model in simulating urban flows and of the applied vegetation model in simulating flow and turbulence in trees was validated. Finally, based on simulations of street canyons with and without avenue-trees, an appropriate turbulent Schmidt number for modeling dispersion in the urban neighborhood was determined as Sct = 0.5.
Mostrar más [+] Menos [-]Human disturbance affects the long-term spatial synchrony of freshwater invertebrate communities
2015
Feio, M.J. | Dolédec, S. | Graça, M.A.S.
Taxonomic and trait composition of invertebrate communities were investigated for 4 reference and 5 disturbed Mediterranean stream sites over a 18 y period, to test the hypotheses that: 1) human disturbance reduces the resilience of communities to extreme climatic events by affecting their functional structure; 2) and as a result, extreme climatic events could lead to asynchronous responses of communities from streams with similar environmental characteristics but differently affected by human disturbance. In reference sites, trait compositions changed differently (were less similar over time) in response to extreme events and variation was less synchronic than taxonomic compositions in the same sites. Oppositely, in disturbed sites there was a marked synchrony in trait composition indicating a functional homogenization in response to human pressures. This limitation in “functional diversity” may involve a lower ability to respond to climatic extreme events and also a reduced potential in ecosystem services.
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