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Co-polymerization of penta-halogenated phenols in humic substances by catalytic oxidation using biomimetic catalysis Full text
2012
Fontaine, Barbara | Piccolo, Alessandro
INTRODUCTION: A synthetic water-soluble meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrinate of iron(III) chloride, Fe-(TDCPPS)Cl, was employed to catalyze the oxidative co-polymerization of penta-halogenated phenols in two humic materials of different origin. MATERIALS AND METHODS: Co-polymerization of pentachlorophenol (PCP) was followed by high-performance size-exclusion chromatography (HPSEC), the unbound PCP recovered from reacting humic solutions was evaluated by gas-chromatography/electron capture detector, and the oxidative catalyzed coupling of pentafluorophenol (PFP) into humic matter was assessed by liquid-state 19F-NMR spectroscopy. HPSEC showed that the catalyzed oxidative coupling between PCP and humic molecules increased the apparent weight-average molecular weight (M w) values in both humic substances. RESULTS AND DISCUSSION: HPSEC further indicated that the co-polymerization reaction turned the loosely bound humic supramolecular structures into more stable conformations, which could no longer be disrupted by the disaggregating effect of acetic acid. The occurrence of covalent linkages established between PCP and humic molecules was also suggested by the very little amount of PCP found free in solution after the catalyzed co-polymerization. 19F-NMR spectroscopy suggested that also PFP could be oxidatively coupled to humic materials. PFP-humic co-polymerization reaction produced 19F-spectra with many more 19F signals and wider chemical shifts spread than for PFP alone or PFP subjected to catalyzed coupling without humic matter. CONCLUSIONS: These findings show that biomimetic iron-porphyrin is an efficient catalyst for the covalent binding of polyhalogenated phenols to humic molecules, thereby suggesting that the co-polymerization reaction may become a useful technology to remediate soils and waters contaminated by polyhalogenated phenols and their analogues.
Show more [+] Less [-]Response to W. Kramer: The human sex odds at birth after the atmospheric atomic bomb tests, after Chernobyl, and in the vicinity of nuclear facilities: comment (doi:10.1007/s11356-011-0644-8) Full text
2012
Scherb, Hagen | Voigt, Kristina
INTRODUCTION: This paper is in response to criticism of our article “The human sex odds at birth after the atmospheric atomic bomb tests, after Chernobyl, and in the vicinity of nuclear facilities” published in Environ Sci Pollut Res 18(5):697–707, 2011. METHODS: Our findings and methods concerning the disturbed human sex odds at birth have been criticized in this journal for being artifacts of data mining, that the concept of statistical significance was misunderstood, and that confounding factors have not been accounted for. Here, we show that this criticism has no basis. We applied well-established statistical methods to large official data sets, and confounding is less important at the level of secular sex odds trends in aggregated annual figures from countries or continents. RESULTS AND CONCLUSIONS: Moreover, our results are strengthened by recent findings concerning increased infant death sex odds in Germany and increased Down syndrome prevalence at birth across Europe after Chernobyl. Prompted by our studies, an official investigation in Lower Saxony, Germany, by the “Niedersächsisches Landesgesundheitsamt (NLGA)” confirmed our observation of severely escalated sex odds within 40 km distance from the nuclear storage site in Gorleben, Germany.
Show more [+] Less [-]NORMACAT project: normalized closed chamber tests for evaluation of photocatalytic VOC treatment in indoor air and formaldehyde determination Full text
2012
Kartheuser, B. | Costarramone, N. | Pigot, T. | Lacombe, S.
BACKGROUND, AIM: The aims of the NORMACAT project are: to develop tools and unbiased standardized methods to measure the performance and to validate the safety of new materials and systems integrating photocatalysis, to develop new photocatalytic media with higher efficiency and to give recommendations aimed at improving the tested materials and systems. METHOD: To achieve this objective, it was necessary to design standardized test benches and protocols to assess photocatalytic efficiency of materials or systems used in the treatment of volatile organic compounds (VOCs) and odour under conditions close to applications. The tests are based on the validation of robust analytical methods at the parts per billion by volume level that not only follow the disappearance of the initial VOCs but also identify the secondary species and calculate the mineralization rates. RESULTS: The first results of inter-laboratory closed chamber tests, according to XP B44-013 AFNOR standard, are described. The photocatalytic degradation of mixtures of several defined pollutants under controlled conditions (temperature, relative humidity, initial concentration) was carried out in two independent laboratories with the same photocatalytic device and with various analytical procedures. Comparison of the degradation rate and of the mineralization efficiency allowed the determination of the clean air delivery rate in both cases. Formaldehyde was the only by-product detected during photocatalytic test under standardized experimental conditions. The concentration of transient formaldehyde varied according to the initial VOC concentration. Moreover the photocatalytic reaction rate of formaldehyde in mixture with other pollutants was analysed. It was concluded that formaldehyde concentration did not increase with time. CONCLUSION—PERSPECTIVE: This type of experiment should allow the comparison of the performances of different photoreactors and of photocatalytic media under controlled and reproducible conditions against mixtures of pollutants including formaldehyde.
Show more [+] Less [-]Monitoring heavy metal pollution by aquatic plants : A systematic study of copper uptake Full text
2012
Materazzi, S. | Canepari, S. | Aquili, S.
INTRODUCTION: The copper bioaccumulation by the floating Lemna minor and by the completely submerged Ranunculus tricophyllus as a function of exposure time and copper concentration was studied, with the aim of proposing these species as environmental biosensors of the water pollution. RESULTS: The results show that both these aquatic angiosperms are good indicators of copper pollution because the copper uptake is the only function of metal concentration (water pollution). CONCLUSION: Uptake behavior is reported as a function of the time and concentration, based on the results of a 3-year study. Kinetic evaluations are proposed.
Show more [+] Less [-]VOC amounts in ambient areas of a high-technology science park in Taiwan: their reciprocal correlations and impact on inhabitants Full text
2012
Liu, Hsin-Wang | Wu, Bei-Zen | Nian, Hung-Chi | Chen, Hsing-Jung | Lo, Jiunn-Guang | Chiu, Kong-Hwa
INTRODUCTION: This study presents bihourly, seasonal, and yearly concentration changes in volatile organic compounds (VOCs) in the inlet and effluent water of the wastewater treatment plant (WWTP) of a high-technology science park (HTIP) in Taiwan, with the VOC amounts at different sites correlated geologically. MATERIALS AND METHODS: This research adopted a combination of two systems, solid-phase microextraction with a gas chromatography/flame ionization detector and an assembly of purge and trap coupled with gas chromatography/mass spectrometry, to monitor polar and nonpolar VOCs in wastewater. This paper investigated the total VOCs, acetone, isopropyl alcohol (IPA), and dimethylsulfide (DMS) concentrations in real water samples collected in the ambient area of the HTIP. RESULTS AND DISCUSSION: The major contents of VOCs measured in the effluent of the WWTP in the HTIP and the surrounding river region were DMS (14–176 ppb), acetone (5–95 ppb), and IPA (15–316 ppb). In comparison with the total VOCs in the inlet wastewater of the WWTP, no corresponding relationship for total VOC concentration in the wastewater was observed between the inlet water and effluent water of the WWTP. CONCLUSIONS: The peak VOC concentrations appeared in the third season, and the correlation of different VOC amounts reflects the production situation of the factories. In addition, VOC concentrations at different sites indicate that the Ke-Ya River is seemingly an effective channel for transporting wastewater to its final destination. The data are good indications for the management of environmental pollution near the HTIP.
Show more [+] Less [-]The occurrence and environmental effect of persistent organic pollutants (POPs) in Taurus Mountains soils Full text
2012
Turgut, Cafer | Atatanir, Levent | Mazmanci, Birgül | Mazmanci, Mehmet Ali | Henkelmann, Bernhard | Schramm, Karl-Werner
PURPOSE: Persistent organic pollutants (POPs) are of global concern due to their ubiquitous presence and toxicity. The occurence of polychlorinated dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs), co-planar biphenyls (PCBs), hexachlorocyclohexanes (HCH), dichlorodiphenyltrichloroethanes (DDT), and organochlorine pesticides (OCPs) in forest soil collected from Taurus mountains may have adverse effects on the environment and health. The aim of the study was to investigate the outcome and distribution of POPs in the environment and the possible grasshopper effect along an altitude transect from sea level up to nearly 2,000 m a.s.l at a spatial distance of about 60 km in the southeastern Turkish Mediterranean Sea. METHODS: The samples were collected at a height of 121, 408, 981, 1,225, 1,373, 1,639, and 1,881 m above sea level from Taurus Mountains, Turkey. The results were confirmed using high-resolution gas chromatography–high-resolution mass spectrometry. RESULTS: The levels of the PCDD in forest soil from Taurus Mountains varied from nearly 4 to 12 pg g−1 dry weight (dw). PCDF concentrations ranged from 2 to 7 pg g−1 dw. Considerably high DDT levels detected in five stations indicated (3,223–24,564 pg g−1) its extensive local application or atmospheric transport. PCB levels were determined between 80 and 288 pg g−1 dw. HCH concentrations ranged from 141 to 1,513 pg g−1 dw. The other OCP was between 102 and 731 pg g−1. CONCLUSION: Although the use of POPs has been banned, our results show that they could still be found in Turkey. Their presence may be attributed to the degradation of pesticides which are newly banned and, as well as to the atmospheric migration and deposition. The lattitude of sampling sites, the chemical, and physical parameters of soil have observed no effect on the fate of POPs in the environment.
Show more [+] Less [-]Production of monoclonal antibody and application in indirect competitive ELISA for detecting okadaic acid and dinophytoxin-1 in seafood Full text
2012
Lu, Shi-Ying | Zhou, Yu | Li, Yan-Song | Lin, Chao | Meng, Xian-Mei | Yan, Dong-Ming | Li, Zhao-Hui | Yu, Shi-Yu | Liu, Zeng-Shan | Ren, Hong-Lin
BACKGROUND, AIM, AND SCOPE: Okadaic acid (OA) and analogues of dinophysistoxin (DTX) are key diarrheic shellfish poisoning (DSP) toxins, which possibly arouse DSP symptoms by consuming the contaminated shellfish. Because of the stable toxicity in high temperature and the long-term carcinogenicity, the outbreaks of DSP related to consumption of bivalve mollusks contaminated by DSP toxins pose a hazard to public health. Therefore, it is worth developing a fast and reliable analytical method for the detection of OA and analogues in shellfish. In this paper, an indirect competitive enzyme-linked immunosorbent assay (ELISA) (icELISA) for detecting OA and DTX-1 in seafood was developed based on monoclonal antibody (McAb). METHODS: The OA was conjugated to human immunoglobulin G (IgG) and bovine serum albumin (BSA) by the active ester method as the immune antigen and the detective antigen. The spleen cells from BALB/c mice immunized with OA-IgG were fused with SP2/0 myeloma cells. A hybridoma cell line, which secreted McAb against OA, was selected by “limiting dilution” cloning. An icELISA was developed based on immobilized conjugate (OA-BSA) competing the McAb with the free OA in seafood sample. RESULTS: A hybridoma cell line, which secreted IgG1 subclass monoclonal antibody (McAb) against OA, was selected. The IC₅₀ of the McAb for OA and dinophytoxin-1 (DTX-1) were 4.40 and 3.89 ng/mL, respectively. Based on the McAb, an indirect competitive ELISA for detection of OA and DTX-1 in seafood was developed. The regression equation was y = 54.713x − 25.879 with a coefficient correlation of R ² = 0.9729. The linear range and the limit of detection were 0.4–12.5 and 0.45 ng/mL, respectively. The average recovery of OA and DTX-1 spiked shellfish was 82.29% with the coefficient of variation of 7.67%. CONCLUSION: The developed icELISA is a fast, sensitive, and convenient assay for detecting of total amount of OA and DTX-1 in seafood.
Show more [+] Less [-]Heterocatalytic Fenton oxidation process for the treatment of tannery effluent: kinetic and thermodynamic studies Full text
2012
Karthikeyan, S. | Ezhil Priya, M. | Boopathy, R. | Velan, M. | Mandal, A. B. | Sekaran, G.
BACKGROUND, AIM, SCOPE: Treatment of wastewater has become significant with the declining water resources. The presence of recalcitrant organics is the major issue in meeting the pollution control board norms in India. The theme of the present investigation was on partial or complete removal of pollutants or their transformation into less toxic and more biodegradable products by heterogeneous Fenton oxidation process using mesoporous activated carbon (MAC) as the catalyst. MATERIALS AND METHODS: Ferrous sulfate (FeSO4·7H2O), sulfuric acid (36 N, specific gravity 1.81, 98% purity), hydrogen peroxide (50% v/v) and all other chemicals used in this study were of analytical grade (Merck). Two reactors, each of height 50 cm and diameter 6 cm, were fabricated with PVC while one reactor was packed with MAC of mass 150 g and other without MAC served as control. RESULTS AND DISCUSSION: The oxidation process was presented with kinetic and thermodynamic constants for the removal of COD, BOD, and TOC from the wastewater. The activation energy (Ea) for homogeneous and heterogeneous Fenton oxidation processes were 44.79 and 25.89 kJ/mol, respectively. The thermodynamic parameters ΔG, ΔH, and ΔS were calculated for the oxidation processes using Van’t Hoff equation. Furthermore, the degradation of organics was confirmed through FTIR and UV–visible spectroscopy, and cyclic voltammetry. CONCLUSIONS: The heterocatalytic Fenton oxidation process efficiently increased the biodegradability index (BOD/COD) of the tannery effluent. The optimized conditions for the heterocatalytic Fenton oxidation of organics in tannery effluent were pH 3.5, reaction time–4 h, and H2O2/FeSO4·7H2O in the molar ratio of 2:1.
Show more [+] Less [-]Functional traits of soil invertebrates as indicators for exposure to soil disturbance Full text
2012
Hedde, Mickaël | Van Oort, Folkert | Lamy, Isabelle
Functional traits of soil invertebrates as indicators for exposure to soil disturbance Full text
2012
Hedde, Mickaël | Van Oort, Folkert | Lamy, Isabelle
We tested a trait-based approach to link a soil disturbance to changes in invertebrate communities. Soils and macro-invertebrates were sampled in sandy soils contaminated by long-term wastewater irrigation, adding notably organic matter and trace metals (TM). We hypothesized that functional traits of invertebrates depict ways of exposure and that exposure routes relate to specific TM pools. Geophages and soft-body invertebrates were chosen to inform on exposure by ingestion or contact, respectively. Trait-based indices depicted more accurately effects of pollution than community density and diversity did. Exposure by ingestion had more deleterious effects than by contact. Both types of exposed invertebrates were influenced by TM, but geophages mainly responded to changes in soil organic matter contents. The trait-based approach requires to be applied in various conditions to uncorrelate specific TM impacts from those of other environmental factors.
Show more [+] Less [-]Functional traits of soil invertebrates as indicators for exposure to soil disturbance Full text
2012
Hedde, Mickaël | van Oort, Folkert | Lamy, Isabelle
We tested a trait-based approach to link a soil disturbance to changes in invertebrate communities. Soils and macro-invertebrates were sampled in sandy soils contaminated by long-term wastewater irrigation, adding notably organic matter and trace metals (TM). We hypothesized that functional traits of invertebrates depict ways of exposure and that exposure routes relate to specific TM pools. Geophages and soft-body invertebrates were chosen to inform on exposure by ingestion or contact, respectively. Trait-based indices depicted more accurately effects of pollution than community density and diversity did. Exposure by ingestion had more deleterious effects than by contact. Both types of exposed invertebrates were influenced by TM, but geophages mainly responded to changes in soil organic matter contents. The trait-based approach requires to be applied in various conditions to uncorrelate specific TM impacts from those of other environmental factors.
Show more [+] Less [-]Functional traits of soil invertebrates as indicators for exposure to soil disturbance Full text
2012
Hedde , Mickaël (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Van Oort , Folkert (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Lamy , Isabelle (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés)
We tested a trait-based approach to link a soil disturbance to changes in invertebrate communities. Soils and macro-invertebrates were sampled in sandy soils contaminated by long-term wastewater irrigation, adding notably organic matter and trace metals (TM). We hypothesized that functional traits of invertebrates depict ways of exposure and that exposure routes relate to specific TM pools. Geophages and soft-body invertebrates were chosen to inform on exposure by ingestion or contact, respectively. Trait-based indices depicted more accurately effects of pollution than community density and diversity did. Exposure by ingestion had more deleterious effects than by contact. Both types of exposed invertebrates were influenced by TM, but geophages mainly responded to changes in soil organic matter contents. The trait-based approach requires to be applied in various conditions to uncorrelate specific TM impacts from those of other environmental factors.
Show more [+] Less [-]Fallout traces of the Fukushima NPP accident in southern West Siberia (Novosibirsk, Russia) Full text
2012
Melgunov, M. S. | Pokhilenko, N. P. | Strakhovenko, V. D. | Sukhorukov, F. V. | Chuguevskii, A. V.
BACKGROUND: The fallout of artificially produced radioactive isotopes has been recorded at a site in southern West Siberia (54°50′43.6″ N, 083°06′22.4″ E, Novosibirsk, Russia). DISCUSSION: The highest activities of 131I, 134Cs, and 136Cs were found in fresh snow precipitated on 02 April 2011, at 0.83, 0.092, and 0.002 Bq L−1 of meltwater, respectively. The 131I/134Cs ratio decreased from 9.0 on 02 April to 1.2 on 27 April, which is consistent with the radioactive decay of 131I. This fallout can only have originated from the accidental emission of Fukushima Nuclear Power Plant, Japan, in March 2011.
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