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Abstract  

Due to the significance of industrial waste water pollution, which creates severe health hazards in humans, this study concentrates over the reduction and determination of the amounts of toxic metals/pollution parameters in the effluents leached from different processes of the textile industry. The concentrations of metal ions were measured by using neutron activation analysis (NAA) technique. The values of toxic metals such as As (49.1 ± 1.8 mg/L), Cu (42.7 ± 1.5 mg/L), Ni (41.1 ± 3.3 mg/L), Mn (51.1 ± 0.7 mg/L), Sb (1.89 ± 0.04 mg/L), Se (0.41 ± 0.01 mg/L), Co (7.5 ± 0.3 mg/L), Cr (8.5 ± 0.5 mg/L) and Cd (1.21 ± 0.08 mg/L) were found very high in crude textile’s effluents as compared to their standard recommended limits. The immense variation observed among the injurious pollutants of the effluents i.e. pH, temperature, electrical conductivity, turbidity, biological oxygen demands, chemical oxygen demands, total suspended solids, total dissolved solids, total solids etc. The toxic metals and injurious pollutants in the unprocessed effluents have been reduced in the post filtration effluents up to 98% and 96% respectively with the help of an ultra-filtration membrane therapy unit.

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Abstract  

Downcore variation of trace metals in sediment cores along the coastal line is one of the markers to assess the intrusion of industrial pollutants into the aquatic environment. Fifty sediment core samples from the Mumbai Harbour Bay (MHB), were studied for the trace element content. MHB is a recipient of effluents from different industries situated all along its coast around Thane–Belapur region. The average concentrations of Titanium (Ti), Manganese (Mn), Iron (Fe), Nickel (Ni), Copper (Cu), Zinc (Zn) were determined by inductively coupled plasma-optical emission spectroscopy and complemented by analysing with energy dispersive X-ray fluorescence spectrometry. In addition to this, depth profiles of K and Ca were also studied to assess the homogeneity of the geological strata of the region. Trace metals such as Cu, Ni and Zn show enrichment between 16 to 28 cm, whereas, uniform distribution through out the core was observed for K, Ca, Ti, Mn and Fe. Chronology of the heavy metal deposition was predicated based on the average sedimentation rate (0.92 ± 0.08 cm year−1) derived using depth-wise 137Cs concentration profile in core of bottom sediment. The results of the analysis showed that MHB had received excess inputs of Cu, Ni and Zn in the year 1981, 1988 and 1982, respectively. Surface concentration of Cu, Ni, Zn and Fe compared to the reference site indicates moderate pollution in the recent years whereas for elements K, Ca, Ti and Mn, the values are normal indicating MHB unpolluted for the latter elements.

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Abstract  

The present paper focuses on biomonitoring of elemental atmospheric pollution, which is reviewed in terms of larger-scaled biomonitoring surveys in an epidemiological context. Based on the literature information, today’s availability of solar-powered small air filter samplers and fibrous ion exchange materials is regarded as adequate or an even better alternative for biomonitor transplant materials used in small-scaled set-ups, but biomonitors remain valuable in larger-scaled set-ups and in unforeseen releases and accidental situations. In the latter case, in-situ biomonitoring is seen as the only option for a retrospective study: biomoniors are there before one even knows that they are needed. For biomonitoring, nuclear analytical techniques are discussed as key techniques, especially because of the necessary multi-element assessments in both source recognition and single-element interpretation. To live up to the demands in an epidemiological context, larger-scaled in-situ biomonitoring asks for large numbers of samples, and consequently, for large total sample masses, this all to ensure representation of both local situations and survey area characteristics. Possibly, this point should direct studies into new “easy-to-sample” biomonitor organisms, of which high masses and numbers may be obtained in field work, rather than continue with biomonitors such as lichens. This also means that both sample handling and processing are of key importance in these studies. To avoid problems in comparability of analytical general procedures in milling, homogenization and digestion of samples of large masses, the paper proposes to involve only few but high-quality laboratories in the total element assessment routines. In this respect, facilities that can handle large sample masses in the assessment of element concentrations are to be preferred. This all highlights the involvement of large-sample-volume nuclear facilities, which, however, should be upgraded and automated in their operation to ensure the necessary sample throughput in larger-scaled biomonitoring.

Open access
Orvosi Hetilap
Authors: László Endre, Sarolta Láng, Adrienn Vámos, János Bobvos, Anna Páldy, Ildikó Farkas, Zsuzsa Collinsné Horváth, and Mihály János Varró

Bevezetés: A magyarországi asztma prevalencia a legutóbbi 15 évben egyenletesen nőtt, az Országos Korányi TBC és Pulmonológiai Intézet nyilvántartása szerint 2004-ben elérte az 1,8%-ot. A gyermekkori asztma hazai gyakoriságára vonatkozóan csak szórványos felmérésekből származó adatok vannak. Célok: Szerzők célul tűzték ki a területet ellátó gyermekorvosoktól nyert adatok segítségével a budapesti gyermekek asztma prevalenciájának a felmérését 1995-ben, 1999-ben és 2003-ban. Megkísérelték az esetleges változás okát is felderíteni. Módszerek: Ennek érdekében kérdőíveket küldtek a 23 kerületi szakfelügyelő gyermekgyógyász főorvosnak, melyet ők a területet ellátó kollégáknak továbbítottak. Ebben csupán azt kérdezték, hány gyermek tartozik a körzetükbe és közülük hányról tudják biztosan, hogy asztmában szenved. Emellett Budapest 8 pontján folyamatosan mérték a levegő CO, NO 2 , SO 2 , O 3 és szálló por koncentrációját, valamint külön Pesten és Budán a pollenszámot. Eredmények : 1995-ben 11 kerületből 108 gyermekorvos válaszolt. Az általuk kezelt 104.060 gyermek közül 1962-ről tudták, hogy asztmában szenved, ami 1,88±0,87%-os prevalenciát jelent. 1999-ben 22 kerületből, 153 kollégától kaptak választ. A gondozásuk alatt álló 142.679 (0–18 év közötti) gyermek 2,26±0,94%-át asztmásként tartották nyilván (összesen 3228-at). 2003-ban már mind a 23 budapesti kerületből sikerült válaszhoz jutniuk. A 204 kolléga által ellátott 176.049 gyermek között minden eddiginél több (4712) az asztmában szenvedő, ami a prevalencia 2,68±1,31%-ra történő emelkedését jelenti. A növekedés üteme mind 1995 és 1999, mind 1999 és 2003 között szignifikáns (p < 0.0001). Ez a szignifikáns növekedés akkor is igazolható, ha csak azt a 11 kerületet hasonlítjuk össze a vizsgált években, amelyekből már 1995-ben is érkezett válasz. A mért légszennyező anyagok koncentrációja nem nőtt a vizsgált évek alatt és a leginkább allergizáló növények pollenszáma sem emelkedett. Következtetések: Jóval több mint 100 ezer gyermek vizsgálati adata alapján megállapítható, hogy 1995 és 2003 között az asztmás gyermekek aránya másfélszeresére nőtt Budapesten, miközben a légszennyezettség nem romlott és a pollenszám sem emelkedett.

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Community Ecology
Authors: D. M. S. Abessa, B. R. F. Rachid, L. P. Zaroni, M. R. Gasparro, Y. A. Pinto, M. C. Bícego, M. A. Hortellan, J. E. S. Sarkis, P. Muniz, L. B. Moreira, and E. C. P. M. Sousa

Abstract

The Santos Estuarine System (SES) is a complex of bays, islands, estuarine channels, and rivers located on the Southeast coast of Brazil, in which multiple contaminant sources are situated in close proximity to mangroves and other protected areas. In this study, the composition and structure of the macrobenthic communities of SES were described and ninety-nine species were identified, with the predominance of polychaetes and bivalve mollusks. The benthic assemblages also showed strong signs of stress, as indicated by the low abundance, richness and diversity, and the dominance of opportunistic species. Integrated analysis including sediment characteristics related to natural and anthropogenic factors (e.g., sediment chemistry, and toxicity) indicated that benthic fauna from the inner portions of the SES and vicinities of the SSOS diffusers as Santos Bay were affected. Some locations at the mouths of Santos and Sao Vicente estuaries exhibited moderate disturbance. In other sites from the mouth of São Vicente and Bertioga channels, and Santos Bay, the benthic fauna were considered not degraded. Our results suggest that a combination of both environmental factors and contaminants were responsible for the benthic community structure.

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Abstract  

The effect of industrial pollution on the behavior of plutonium and americium was evaluated in a pine forest in the vicinity of a Cu-Ni smelter in SW Finland. Soil and vegetation were sampled at distances of 0.5, 2, 4 and 8 km from the smelter. The vertical distribution of plutonium and americium was studied in litter, organic layer and mineral layers. The amount of Pu and Am in the litter layer increased and that in the organic layer decreased towards the smelter. Concentrations of plutonium and americium in different vegetation species decreased in the order mushrooms > lichens (Cladina spp., Cetraria islandica) > Empetrum nigrum > Vaccinium vitis-idaea.

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Abstract  

The lichen Ramalina celastri (Spreng.) Krog. & Swinsc. was used to study trace-element atmospheric pollution in Córdoba (Argentina). 38 samples from a 1999 campaign were analyzed by NAA and a number of physiological parameters was determined. In first-ever comparisons, no correlations were found between altitude, physiological parameters and determined elements, which allowed the full comparison of element data in lichen samples throughout the whole survey area. After the application of Monte Carlo assisted factor analysis to the elemental matrix, five source profiles were found and mapped. The attribution of the sources is discussed.

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Summary  

An alternative method has been proposed and performed to determine the relevant soil parameters - such as dispersitivity and distribution coefficient - related to the use of a tract of land for a toxic waste repository. The method makes use of radioactive tracers and a geotechnical centrifuge to accelerate relevant migration processes. A few soil types and tracers have been employed. Experimental data were then compared to those predicted by the advection-dispersion equation. Preliminary results indicate that this alternative method is useful for the determination of the above parameters, especially when fine soils are involved.

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Abstract  

The present work shows a methodology for the application of EDXRF with a X-ray tube, in the analysis of elements in the following matrices: microalgae, marine algae, marine sediments and corals. Various methods were applied: one using a relative external standard, a fundamental parameters method, an absolute method based on elemental sensitivity, a method which used X-ray fluorescence excitation measured in the back side of the sample for low contents heavy elements determination and a TRXRF method. The thin layer samples were prepared using a plastic resin. The analyzed samples of marine algae, marine sediments and corals belong to a marine ecosystem from the North of Havana City, the most affected area by natural metereological phenomena and human impact.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: V. Cojocaru, D. I. Strumińska, B. Skwarzec, A. Pantelică, E. Pincovschi, and I. I. Georgescu

Summary  

Elemental concentrations of soil samples collected in the vicinity of a Romanian fertilizer plant were determined by EDXRF and long half-life INAA. Lower limits of detection, obtained for various elements in soil by EDXRF technique with radioactive excitation sources (238Pu and 241Am) and a HPGe detector are presented. Spurious effects characteristic for Ge detector X-ray spectrometry are evaluated and discussed, and methods to overcome this drawback are suggested. Special care was taken to subtract from the spectra the Ge Ka

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