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Characterization of Textile Effluents from Dhaka Export Processing Zone (DEPZ) Area in Dhaka, Bangladesh
2016
Kamal, Abdul Kadir Ibne | Ahmed, Fahad | Hassan, Mahmud | Uddin, Md. Khabir | Hossain, Syed Mohammod
The present study has been undertaken in a laboratory scale to characterize and investigate pollution potential of textile effluents from DEPZ area in Dhaka, Bangladesh. Collected effluent samples from five different industries were analyzed for physico-chemical parameters using field kits and Standard Methods, and for metals using Flame Atomic Absorption Spectrophotometer (FAAS). The average physico-chemical parameters such as temperature, color, pH, DO, EC, BOD, COD, TS, total alkalinity and total hardness were found 52.4 ºC, 2646 PCU, 9.788, 1.492 mg/L, 7473.2 μS/cm, 157 mg/L, 508.8 mg/L, 9140.8 mg/L, 761.2 mg/L and 189.6 mg/L, respectively. The average concentrations of metal found in the textile effluents were in the order of Na (4611.762 mg/L) > Ca (9.166 mg/L) > Mg (3.578 mg/L) > Zn (0.113 mg/L) > Ni (0.0074 mg/L) > Cu (0.0032 mg/L). All the measured physico-chemical parameter values are negatively deviated but metal concentrations (except Na) are positively deviated from standard limits of wastewater discharge set by Department of Environment and US Environmental Protection Agency. In view of those characteristics, the textile industry effluents should be considered to be treated by setting eco-friendly effluent treatment plant (ETP) before directly discharging into the water bodies.
Afficher plus [+] Moins [-]Soil and river contamination patterns of chlordecone in a tropical volcanic catchment in the French West Indies (Guadeloupe)
2016
Crabit, Armand | Cattan, Philippe | Colin, François | Voltz, Marc | Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Fonctionnement écologique et gestion durable des agrosystèmes bananiers et ananas (UR GECO) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)
The aim of this study was to identify primary flow paths involved in the chlordecone (CLD) river contamination and quantify the CLD fluxes to assess CLD pollution levels and duration according to a typical catchment of the banana cropping area in the French Indies (Guadeloupe): the Perou Catchment (12 km(2)) characterized by heavy rainfall (5686 mm year(-1)). Three sub-catchments (SC1, SC2 and SC3) were studied during the hydrological year 2009-2010: a pedological survey combined with a spatialized hydrochemical approach was conducted. The average soil concentration is higher in the Perou Catchment (3400 mu g kg(-1)) than in the entire banana cropping area in Guadeloupe (2100 mu g kg(-1)). The results showed that CLD stocks in soils vary largely among soil types and farming systems: the weakest stocks are located upstream in SC1 (5 kg ha(-1)), where a majority of the area is non-cultivated; medium stocks are located in Nitisols downstream in SC3 (9 kg ha(-1)); and the greatest stocks are observed in SC2 on Andosols (12 kg ha(-1)) characterized by large farms. The annual water balance and the hydro-chemical analysis revealed that the three sub-catchments exhibited different behaviors. Perou River contamination was high during low flows, which highlighted that contamination primarily originated from groundwater contributions. The results showed that only a small part of the catchment (SC2), contributing little to the water flow, comprises a major CLD contribution, which is in agreement with the highly contaminated andosol soils observed there. Another significant result considers that at least 50 years would be required to export the totality of the actual CLD soil stocks retained in the topsoil layer. The actual time for soil remediation will however be much longer considering (i) the necessary time for the chlordecone to percolate and be stored in the shallow aquifers and (ii) its travel time to reach the river.rights reserved.
Afficher plus [+] Moins [-]Plastic burdens in northern fulmars from Svalbard: Looking back 25 years
2022
Collard, France | Bangjord, Georg | Herzke, Dorte | Gabrielsen, Geir W
peer reviewed | The northern fulmar Fulmarus glacialis ingests a larger number of (micro)plastics than many other seabirds due to its feeding habits and gut morphology. Since 2002, they are bioindicators of marine plastics in the North Sea region, and data are needed to extend the programme to other parts of their distribution areas, such as the Arctic. In this study, we provide data on ingested plastics by fulmars collected in 1997 in Kongsfjorden, Svalbard. An extraction protocol with KOH was used and for half of the birds, the gizzard and the proventricular contents were analysed separately. Ninety-one percent of the birds had ingested at least one piece of plastic with an average of 10.3 (±11.9 SD) pieces. The gizzards contained significantly more plastics than the proventriculus. Hard fragments and polyethylene were the most common characteristics. Twelve percent of the birds exceeded the EcoQO value of 0.1 g.
Afficher plus [+] Moins [-]Investigation of microplastic pollution in Arctic fjord water: a case study of Rijpfjorden, Northern Svalbard
2022
Bao, Mengrong | Huang, Qinghui | Lu, Zhibo | Collard, France | Cai, Minggang | Huang, Peng | Yu, Yong | Cheng, Shuiping | An, Lihui | Wold, Anette | Gabrielsen, Geir Wing
peer reviewed | Microplastic contamination is an emerging issue in the marine environment including the Arctic. However, the occurrence of microplastics in the Arctic fjords remains less understood. Sample collections were conducted by trawling horizontally in surface water (0-0.4-m depth) and trawling vertically in the water column (0-200-m depth) to investigate the abundance, composition, and distribution of microplastics in the Rijpfjorden, Northern Svalbard, in the summer of 2017. Laser Direct Infrared chemical imaging technique was applied for the counting and identification of microplastic particles. A total of 1010 microplastic particles and 14 mesoplastics were identified from 41,038 particles in eight samples from the Rijpfjorden. The abundance of microplastics larger than 300 µm was 0.15 ± 0.19 n/m3 in surface water, and 0.15 ± 0.03 n/m3 in the water column of the Rijpfjorden. The microplastic particles identified in Rijpfjorden water consisted of 10 types of polymers. The dominant microplastics are polyurethane, polyethylene, polyvinyl acetate, polystyrene, polypropylene, and alkyd varnish. Historical ship activities and newly melted sea ice might be major sources of microplastics in the seawater of Rijpfjorden. In general, contamination of microplastics larger than 300 µm in Rijpfjorden water is at a low level in comparison to other polar waters. Further research is needed to confirm the origin and fate of microplastics below 300 µm in Arctic fjords.
Afficher plus [+] Moins [-]A novel in situ method for sampling urban soil dust: Particle size distribution, trace metal concentrations, and stable lead isotopes
2013
Bi, Xiangyang | Liang, Siyuan | Li, Xiangdong
In this study, a novel in situ sampling method was utilized to investigate the concentrations of trace metals and Pb isotope compositions among different particle size fractions in soil dust, bulk surface soil, and corresponding road dust samples collected within an urban environment. The aim of the current study was to evaluate the feasibility of using soil dust samples to determine trace metal contamination and potential risks in urban areas in comparison with related bulk surface soil and road dust. The results of total metal loadings and Pb isotope ratios revealed that soil dust is more sensitive than bulk surface soil to anthropogenic contamination in urban areas. The new in situ method is effective at collecting different particle size fractions of soil dust from the surface of urban soils, and that soil dust is a critical indicator of anthropogenic contamination and potential human exposure in urban settings.
Afficher plus [+] Moins [-]Upward and downward solar-induced chlorophyll fluorescence yield indices of four tree species as indicators of traffic pollution in Valencia
2013
Van Wittenberghe, Shari | Alonso, Luis | Verrelst, Jochem | Hermans, Inge | Delegido, Jesús | Veroustraete, Frank | Valcke, Roland | Moreno, José | Samson, Roeland
Passive steady-state chlorophyll fluorescence (Fs) provides a direct diagnosis of the functional status of vegetation photosynthesis. With the prospect of mapping Fs using remote sensing techniques, field measurements are mandatory to understand to which extent Fs allows detecting plant stress in different environments. Trees of four common species in Valencia were classified in either a low or a high local traffic exposure class based on their leaf magnetic value. Upward and downward hyperspectral fluorescence yield (FY) and indices based on the two Fs peaks (at 687 and 741 nm) were calculated. FY indices of P. canariensis and P. x acerifolia were significantly different between the two traffic exposure classes defined, but not for C. australis nor M. alba. While chlorophyll content could not indicate the difference between low and high traffic exposure, the FY(687)/FY(741) peak ratio increased significantly (p < 0.05) for both leaf sides for the higher traffic exposure class.
Afficher plus [+] Moins [-]Atmospheric concentrations and potential sources of PCBs, PBDEs, and pesticides to Acadia National Park
2013
Sofuoglu, Sait C. | Sofuoglu, Aysun | Holsen, Thomas M. | Alexander, Colleen M. | Pagano, James J.
This study assessed concentrations and investigated potential source regions for PCBs, PBDEs, and organochlorine pesticides in Acadia National Park, Maine, USA. Back-trajectories and potential source contribution function (PSCF) values were used to map potential source areas for total-PCBs, BDE-47, and 10 organochlorine pesticides. The constructed PSCF maps showed that ANP receives high pollutant concentrations in air masses that travel along four main pathways: (1) from the SW along the eastern Atlantic seaboard, (2) from the WSW over St. Louis, and Columbus regions, (3) from the west over Chicago, and Toronto regions, and (4) from WNW to NNW over the Great Lakes, and Quebec regions. Transport of all studied pollutants were equally distributed between the first three pathways, with only minor contributions from the last pathway. This study concludes that the high-pollutant concentrations arriving at ANP do not exclusively originate from the major urban centers along the eastern Atlantic seaboard.
Afficher plus [+] Moins [-]Heterogeneity of atmospheric ammonia at the landscape scale and consequences for environmental impact assessment
2013
Vogt, Esther | Dragosits, Ulrike | Braban, Christine F. | Theobald, Mark R. | Dore, Anthony J. | van Dijk, Netty | Tang, Y Sim | McDonald, Chris | Murray, Scott | Rees, R. M. (Robert M.) | Sutton, Mark A.
We examined the consequences of the spatial heterogeneity of atmospheric ammonia (NH3) by measuring and modelling NH3 concentrations and deposition at 25 m grid resolution for a rural landscape containing intensive poultry farming, agricultural grassland, woodland and moorland. The emission pattern gave rise to a high spatial variability of modelled mean annual NH3 concentrations and dry deposition. Largest impacts were predicted for woodland patches located within the agricultural area, while larger moorland areas were at low risk, due to atmospheric dispersion, prevailing wind direction and low NH3 background. These high resolution spatial details are lost in national scale estimates at 1 km resolution due to less detailed emission input maps. The results demonstrate how the spatial arrangement of sources and sinks is critical to defining the NH3 risk to semi-natural ecosystems. These spatial relationships provide the foundation for local spatial planning approaches to reduce environmental impacts of atmospheric NH3.
Afficher plus [+] Moins [-]Mercury and methylmercury bioaccumulation by polychaete worms is governed by both feeding ecology and mercury bioavailability in coastal mudflats
2013
Sizmur, Tom | Canário, João | Gerwing, Travis G. | Mallory, Mark L. | O'Driscoll, Nelson J.
Polychaete worms are abundant in many mudflats but their importance to coastal food web Hg biomagnification is not known. We sampled sediments and polychaete worms from mudflats in the Bay of Fundy to investigate the bioaccumulation of mercury (Hg) and methylmercury (MeHg) in the coastal invertebrate food web. Hg concentrations in the sediments were low (<20 μg kg−1). Labile Hg (methanol/KOH sediment extraction) in surface sediments (0–1 cm) was positively correlated with Hg bioaccumulation by surface sediment-ingesting polychaetes but, surprisingly, there was a negative correlation between δ15N (i.e. trophic level) and THg bioaccumulation factors in polychaete worms. Worms feeding on deeper sediments contained the greatest MeHg concentrations (69.6 μg kg−1). Polychaetes are an important vector for Hg biomagnification to the coastal avian food web. This research demonstrates that feeding depth and method of feeding are more important than trophic position or sediment Hg concentrations for predicting Hg bioaccumulation.
Afficher plus [+] Moins [-]Enhanced PCBs sorption on biochars as affected by environmental factors: Humic acid and metal cations
2013
Wang, Yu | Wang, Lei | Fang, Guodong | Herath, H.M.S.K. | Wang, Yujun | Cang, Long | Xie, Zubin | Zhou, Dongmei
Biochar plays an important role in the behaviors of organic pollutants in the soil environment. The role of humic acid (HA) and metal cations on the adsorption affinity of polychlorinated biphenyls (PCBs) to the biochars in an aqueous medium and an extracted solution from a PCBs-contaminated soil was studied using batch experiments. Biochars were produced with pine needles and wheat straw at 350 °C and 550 °C under anaerobic condition. The results showed that the biochars had high adsorption affinity for PCBs. Pine needle chars adsorbed less nonplanar PCBs than planar ones due to dispersive interactions and separation. Coexistence of HA and metal cations increased PCBs sorption on the biochars accounted for HA adsorption and cation complexation. The results will aid in a better understanding of biochar sorption mechanism of contaminants in the environment.
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