Determination of chlorinated paraffins in sediments from the Firth of Clyde by gas chromatography with electron capture negative ionisation mass spectrometry and carbon skeleton analysis by gas chromatography with flame ionisation detection

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Ines Hussy, Lynda Webster, Marie Russell, Colin Moffat

Short chain chlorinated paraffins (SCCPs) are a group of persistent organic pollutants (POPs) of increasing concern, but are to date not widely investigated in the environment, largely due to the challenges involved in their quantification. Here, SCCPs were quantified in marine sediments from the Firth of Clyde, Scotland, by gas chromatography with electron capture negative ionisation mass spectrometry (GC–ECNIMS) and through carbon skeleton analysis by gas chromatography with flame ionisation detection (GC–FID), and the analytical challenges encountered are discussed. Concentrations in the sediments ranged from 0.4 to 69?gkg^?1 when determined by GC–ECNIMS, and from 5.6 to 379?gkg^?1 when determined by GC–FID. For 8 out of 11 samples, analysis by GC–FID gave higher results than analysis by GC–ECNIMS. Unexpected aspects of the analysis, such as the presence of high concentrations of longer chain chlorinated paraffins in the samples, are also presented.

Highlights

Posted on 28 May 2012 | 12:52 pm

Polychlorobiphenyls and organochlorine pesticides in conventional and organic brands of milk: Occurrence and dietary intake in the population of the Canary Islands (Spain)

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

O.P. Luzardo, M. Almeida-González, L.A. Henríquez-Hernández, M. Zumbado, E.E. Álvarez-León, L.D. Boada

The population of the Spanish archipelago of the Canary Islands has been studied in depth regarding its levels of contamination by organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs). Foodstuffs of animal origin, such as milk, are prominent contributors to the body burden of these contaminants. As this population presents one of the highest milk-intake in Spain and Europe, we evaluated the level of OCs and PCBs in 26 commercially available brands of milk (16 conventional and 10 organic brands) present in the market of these Islands, in order to estimate the relevance of milk as a source of these chemicals for the Canary population. Our findings showed that hexachlorobenzene, trans-chlordane, and PCB153 were present in almost all the samples with independence of the type of milk. For both types of milks, the concentration of OCs was very low, showing organic milks lower levels than conventional ones. As a consequence, the estimated daily intake for OCs was lower than the tolerable daily intake (TDI) established by International Agencies. The levels of PCBs in milk were also found to be very low, but, in this case, the situation was the opposite: there were higher levels of PCBs in organic than in conventional brands of milk. Unexpectedly, levels of dioxin-like PCBs (DL-PCBs) reached values higher than 25pg WHO-TEQ g^?1 fat in percentile 75 for both types of milk indicating the existence of a number of brands of milk highly contaminated by these toxicants. Consequently, the population who consume the most contaminated milk brands could have estimated daily intakes well above the recommended TDI (2pg WHO-TEQ kg^?1 b.w.d^?1) established by European Union Authorities. These results are of concern if we consider the well known adverse health effects exerted by dioxin-like compounds.

Highlights

Posted on 28 May 2012 | 12:52 pm

DFT M06-2X investigation of alkaline hydrolysis of nitroaromatic compounds

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Frances C. Hill, Liudmyla K. Sviatenko, Leonid Gorb, Sergiy I. Okovytyy, Gail S. Blaustein, Jerzy Leszczynski

The nitroaromatic compounds 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT) and 2,4-dinitroanisole (DNAN) are potential environmental contaminants and their transformations under a variety of environmental conditions are consequently of great interest. One possible method to safely degrade these nitrocompounds is alkaline hydrolysis. A mechanism of the initial stages of this reaction was investigated computationally. Simulations of UV–VIS and NMR spectra for this mechanism were also produced. The results obtained were compared to available experimental data on the alkaline hydrolysis of TNT and suggest that the formation of Meisenheimer complexes and an anion of TNT are potential first-step intermediates in the reaction path. As the reaction proceeds, computational results indicate that polynegative complexes dominate the degradation pathway, followed by cycles of carbon chain opening and breaking. A second possible pathway was identified that leads to polymeric products through Janovsky complex formation. Results from this study indicate that the order of increasing resistance to alkaline hydrolysis is TNT, DNT and DNAN.

Graphical abstract

Graphical abstract Highlights

Posted on 28 May 2012 | 12:52 pm

Chronic exposure to contaminated drinking water stimulates PPAR expression in mice livers

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Peng Shi, Xu-Xiang Zhang, Zongyao Zhang, Yan Zhang, Bing Wu, Shupei Cheng, Aimin Li

Mice were fed with source water (SW) and tap water (TW) for 90d to evaluate hepatotoxicity induced by the drinking water. Histopathologic observation showed no obvious damage to hepatic tissue in the SW and TW groups. However, microarray analysis indicated that the SW and TW exposures affected many metabolic pathways, among which PPAR (peroxisome proliferator-activated receptors) signaling was most susceptible. Immunohistochemical staining demonstrated that both PPAR-? and PPAR-? were significantly increased in the exposure groups compared to control. Enzyme-linked immunosorbent assay revealed that PPAR-? expression level was increased from 23.37±0.53ngg^?1 liver weight in control group to 26.60±1.43ngg^?1 liver weight in SW group and 27.68±1.10ngg^?1 liver weight in TW group (p <0.05). For PPAR-?, the expression level was also significantly enhanced from 0.83±0.07ngg^?1 liver weight in control group to 1.11±0.20ngg^?1 liver weight in SW group and 1.16±0.07ngg^?1 liver weight in TW group (p <0.05). The SW and DW posed no obvious hepatotoxicity on mice and PPAR-?/-? could be used as a novel biomarker to assess public health risk induced by slightly contaminated drinking water.

Highlights

Posted on 28 May 2012 | 12:52 pm

Editorial Board

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Posted on 28 May 2012 | 12:52 pm

Lactational transfer of mercury and polychlorinated biphenyls in polar bears

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Katrina K. Knott, Daryle Boyd, Gina M. Ylitalo, Todd M. O’Hara

We examined concentrations of total mercury (tHg, inorganic and methylated forms) and polychlorinated biphenyls (PCBs) in blood and milk from free-ranging Southern Beaufort–Chukchi Sea polar bears (Ursus maritimus) to assess maternal transfer of contaminants during lactation and the potential health risk to nursing young. Concentrations of contaminants in the blood of dependent and juvenile animals (ages 1–5years) ranged from 35.9 to 52.2?gkg^?1 ww for tHg and 13.9 to 52.2?gkg^?1 ww (3255.81–11067.79?gkg^?1 lw) for ?PCB7s, similar to those of adult females, but greater than adult males. Contaminant concentrations in milk ranged from 5.7 to 71.8?g tHg kg^?1 ww and 160 to 690?g ?PCB11s kg^?1 ww (547–5190?gkg^?1 lw). The daily intake levels for tHg by milk consumption estimated for dependent young were below the tolerable daily intake level (TDIL) of tHg established for adult humans. Although the daily intake levels of PCBs through milk consumption for cubs of the year exceeded the TDIL thresholds, calculated dioxin equivalents for PCBs in milk were below adverse physiological thresholds for aquatic mammals. Relatively high concentrations of non-dioxin like PCBs in polar bear milk and blood could impact endocrine function of Southern Beaufort–Chukchi Sea polar bears, but this is uncertain. Transfer of contaminants during mid to late lactation likely limits bioaccumulation of dietary contaminants in female polar bears during spring. As polar bears respond to changes in their arctic sea ice habitat, the adverse health impacts associated with nutritional stress may be exacerbated by tHg and PCBs exposure, especially in ecologically and toxicologically sensitive polar bear cohorts such as reproductive females and young.

Highlights

Posted on 28 May 2012 | 12:52 pm

Spatial trend and pollution assessment of total mercury and methylmercury pollution in the Pearl River Delta soil, South China

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Laiguo Chen, Zhencheng Xu, Xiaoyong Ding, Weidong Zhang, Yumei Huang, Ruifang Fan, Jiaren Sun, Ming Liu, Donglin Qian, Yongbin Feng

Total mercury (THg) and methylmercury (MeHg) were measured in large number of soil samples collected from areas with different types of land use, different depth in the Pearl River Delta (PRD) of South China. THg and MeHg concentrations ranged from 16.7 to 3320ngg^?1 and 0.01 to 1.34ngg^?1, respectively. THg levels are highest in the top 0–20cm soil layer, and decrease from the surface to bottom layer soil. Spatial variation was observed with different types of land use. Urban parks had the highest concentrations and the other areas tended to decrease in the order of residential areas, industrial areas, vegetable fields, cereal fields, and woodlands. Temporal variation was also noted, and two relatively high THg contamination zones located in the northwestern part of the PRD have significantly expanded over the last two decades. Both THg and MeHg concentrations were correlated significantly with soil organic matter (OM), but not with soil pH. THg pollution status was evaluated using two assessment methods.

Highlights

Posted on 28 May 2012 | 12:52 pm

Stability considerations of aspartame in the direct analysis of artificial sweeteners in water samples using high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS)

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Jean-Daniel Berset, Nicole Ochsenbein

A HPLC–MS/MS method is presented for the simultaneous determination of frequently used artificial sweeteners (ASs) and the main metabolite of aspartame (ASP), diketopiperazine (DKP), in environmental water samples using the direct-injection (DI) technique, thereby achieving limits of quantification (LOQ) of 10ngL^?1. For a reliable quantification of ASP pH should be adjusted to 4.3 to prevent formation of the metabolite. Acesulfame (ACE), saccharin (SAC), cyclamate (CYC) and sucralose (SUC) were ubiquitously found in water samples. Highest concentrations up to 61?gL^?1 of ACE were found in wastewater effluents, followed by surface water with concentrations up to 7?gL^?1, lakes up to 600ngL^?1 and groundwater and tap water up to 70ngL^?1. The metabolite DKP was only detected in wastewater up to 200ngL^?1 and at low detection frequencies.

Highlights

Posted on 28 May 2012 | 12:52 pm

Editorial Board

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Posted on 28 May 2012 | 12:52 pm

Sorption of 17?-ethinyl estradiol, bisphenol A and phenanthrene to different size fractions of soil and sediment

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Ke Sun, Jie Jin, Bo Gao, Zheyun Zhang, Ziying Wang, Zezhen Pan, Dongyu Xu, Ye Zhao

The potential for negative effects caused by endocrine disrupting chemicals (EDCs) release into the environment is a prominent concern and numerous research projects have investigated possible environmental fate and toxicity. However, their sorption behavior by size fractions of soil and sediment has not been systematically represented. The sorption of bisphenol A (BPA), 17?-ethinyl estradiol (EE2) and phenanthrene (Phen) by different size fractions of soil and sediment were investigated. Sorption isotherms of EE2, BPA, and Phen by size fractions of soil (SL) and sediment (ST) were well fitted to the Freundlich model. The positive correlation between EE2, BPA and Phen sorption capacity (log K d) of size fractions and their organic carbon (OC) content suggests that OC of size fractions in SL and ST should regulate sorption, while the surface area (SA) of size fractions may not account for sorption of EE2, BPA and Phen. Each size fraction of ST had higher sorption capacity (K d or K OC) of EE2 and BPA than that of SL due to their difference in the polarity of organic matter (OM) between terrestrial and aquatic sources. Sorption capacity logK d for size fractions of SL and ST did not follow the order: clay>silt>sand due to the difference in OM abundance and composition between the size fractions. Large particle fractions of ST contributed about 80% to the overall sorption for any EE2, BPA, and Phen. This study was significant to evaluate size fractions of soil and sediment as well as their associated OM affecting EE2 and BPA sorption processes.

Highlights

Posted on 28 May 2012 | 12:52 pm

Bioindication of volatile elements emission by the Puyehue–Cordón Caulle (North Patagonia) volcanic event in 2011

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Débora Bubach, Soledad Pérez Catán, María Arribére, Sergio Ribeiro Guevara

The emission of volatile pollutants from the volcanic eruption of the Puyehue–Cordón Caulle complex (North Patagonia Andean Range) that started in June 4th, 2011, was investigated by bioindication means with the epyphytic fruticose lichen Usnea sp. The elemental composition of pooled samples made up with 10 lichen thalli were analysed by Instrumental Neutron Activation Analysis. Eleven sampling sites were selected within the impacted region at different distance from the volcanic source. Five sites were selected as they were already sampled in a previous study prior to the eruption. Two other new sampling sites were selected from outside the impacted zone to provide non-impacted baseline sites. The elements associated with the lichen incorporation of particulate matter (PM) of geological origin were identified by linear correlation with a geochemical tracer (Sm concentrations). The elements associated with PM uptake were Ce, Eu, Fe, Hf, La, Lu, Na, Nd, Sb, Sc, Se, Ta, Tb, Th, U, and Yb. Arsenic and Cs concentrations showed contributions exceeding the PM fraction in sites near the volcanic centre, also higher than the baseline concentrations, which could be associated with permanent emissions from the geothermal system of the Puyehue–Cordón Caulle complex. The lichen concentrations of Ba, Ca, Co, Hg, K, Rb, Sr, and Zn were not associated with the PM, not showing higher concentrations in the sites nearby the volcanic source or respect to the baseline values either. Therefore, there is no indication of the emission of volatile forms of these elements in the lichen records. The lichen records only identified Br volatile emissions associated with the Puyehue–Cordón Caulle complex eruption in 2011.

Highlights

Posted on 28 May 2012 | 12:52 pm

Arsenic methylation, GSTO1 polymorphisms, and metabolic syndrome in an arseniasis endemic area of southwestern Taiwan

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Jein-Wen Chen, Shu-Li Wang, Ya-Hui Wang, Chien-Wen Sun, Yeou-Lih Huang, Chien-Jen Chen, Wan-Fen Li

Previous studies have shown that hair arsenic (As) levels are associated with an increased prevalence of metabolic syndrome (MetS), which is a strong predictor for type 2 diabetes. The objective of this study was to evaluate whether urinary arsenic methylation is related to MetS in an arseniasis endemic area of southwestern Taiwan, taking genetic factors into account. Subjects were from a community-based cohort recruited in 1990 from three villages in Putai Township. In 2002–2003, we successfully followed 247 subjects and measured their urinary arsenic species including inorganic arsenic, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), as well as the coding region polymorphisms of three genes known to involve in arsenic methylation. Results showed that subjects of MetS had a history of consuming well water of higher arsenic concentration as compared to those without MetS. We also found a significant association between urinary arsenic species and risk for MetS, where the odds ratio of MetS was increased with decreasing proportion of MMA and low rate of primary methylation (defined as MMA/inorganic As). The increased risk associated with low primary methylation rate was further modified by the GSTO1 A140D polymorphism, with the D allele carriers showing a slightly higher risk for MetS. Our results suggest that a low MMA% is associated with increased risk for MetS among As-exposed subjects and the genetic polymorphism of GSTO1, an enzyme responsible for the reduction of pentavalent arsenic species, may also play a modest modification role.

Highlights

Posted on 28 May 2012 | 12:52 pm

Investigating differential binding of polychlorinated dibenzo-p-dioxins/dibenzofurans in soil and soil components using selective supercritical fluid extraction

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Steven B. Hawthorne, Yunzhou Chai, Carol B. Grabanski, John W. Davis, Michael Wilken, Greg D. Martin, David J. Miller, Upal Ghosh

Supercritical fluid extraction (SFE) with pure carbon dioxide was performed at increasingly strong conditions to investigate differential binding of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) in two impacted soils, in their sieved size fractions, and in small (a few mg) samples of industry-related waste products separated from impacted soil. The binding strengths of PCDD/Fs were shown to be different in the two soils, and in their different soil particle size fractions. As might be expected based on surface area considerations, one soil showed the strongest binding in the smallest (<5?m) sieved fraction. However, the other soil showed the strongest binding in the larger sized fractions, possibly indicating that process-related particles could be controlling PCDD/F binding. Selective SFE of various types of particles including black carbon and charcoal (separated from soil), and from a suspected process anode residue did show different PCDD/F binding behavior ranging from quite weak binding (charcoal) to very strong binding (anode particles). Shifts to the stronger SFE fractions in the soils after activated carbon treatment agreed well with the decreases previously found in the uptake of PCDD/Fs by earthworms, as well as decreases in their freely-dissolved aqueous concentrations in soil/water slurries. These results show that, as previously demonstrated for PAHs and PCBs, selective SFE can be a useful tool to investigate differences in PCDD/F binding behaviors in impacted soils and sediments and their component parts, as well as a rapid tool for estimating the effectiveness of activated carbon treatments on decreasing the bioavailability of PCDD/Fs in soils and sediments.

Highlights

Posted on 28 May 2012 | 12:52 pm

Leaching of azoxystrobin and its degradation product R234886 from Danish agricultural field sites

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Lisbeth Flindt Jørgensen, Jeanne Kjær, Preben Olsen, Annette Elisabeth Rosenbom

The objective was to estimate leaching of the fungicide azoxystrobin (methyl (?E)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-?-(methoxymethylene)benzene-acetate) and one of its primary degradation products R234886 ([(E)-2-(2-[6-cyanophenoxy)-pyrimidin-4-yloxyl]-phenyl-3-methoxyacrylic acid], major fraction) at four agricultural research fields (one sandy and three loamy) in Denmark. Water was sampled from tile drains, suction cups and groundwater wells for a minimum period of two years after application of azoxystrobin. Neither azoxystrobin nor R234886 were detected at the sandy site, but did leach through loamy soils. While azoxystrobin was generally only detected during the first couple of months following application, R234886 leached for a longer period of time and at higher concentrations (up to 2.1?gL^?1). Azoxystrobin is classified as very toxic to aquatic organisms and R234886 as very harmful. Our study shows that azoxystrobin and R234886 can leach through loamy soils for a long period of time following application of the pesticide and thereby pose a potential threat to vulnerable aquatic environments and drinking water resources. We thus recommend the inclusion of azoxystrobin and R234886 in pesticide monitoring programmes and further investigation of their long-term ecotoxicological effects.

Highlights

Posted on 28 May 2012 | 12:52 pm

Organochlorine pesticides in soil under irrigated cotton farming systems in Vertisols of the Namoi Valley, north-western New South Wales, Australia

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Timothy B. Weaver, Hossein Ghadiri, Nilantha R. Hulugalle, Stephen Harden

Organochlorine pesticides (OCPs) such as DDT and DDE have been detected in the surface 0.2m of Vertisols in the lower Namoi Valley of north western New South Wales, Australia even though they have not been applied to crops since 1982. However, their presence in the deeper soil horizons has not been investigated. The objective of this study was to determine if OCPs were present to a depth of 1.2m in Vertisols under irrigated cotton farming systems in the lower Namoi Valley of New South Wales. Soil was sampled from the 0–1.2m depths in three sites, viz. the Australian Cotton Research Institute, ACRI, near Narrabri (149°36?E, 30°12?S), and two cotton farms near Wee Waa (149°27?E, 30°13?S) and Merah North (149°18?E, 30°12?S) in northern New South Wales, Australia. The OCPs detected and their metabolites were ?-endosulfan, ?-endosulfan, endosulfan sulphate, DDD, DDE, DDT and endrin. The metabolite DDE, a breakdown product of DDT, was the most persistent OCP in all depths analysed. Endosulfan sulphate was the second most persistent followed by endrin>?-endosulfan>?-endosulfan>DDT and DDD. DDT was sprayed extensively in the lower Namoi Valley up to the early 1980s and may explain the persistence of DDE in the majority of soil samples. Dicofol and Dieldrin, two OCPs previously undocumented in Vertisols were also detected. The movement of OCPs into the subsoil of Vertisols may occur when irrigation or rain transports soil colloids and organic matter via preferential flow systems into the deeper layers of a soil profile. Persistence of OCPs was closely correlated to soil organic carbon concentrations. The persistence in soil of OCP’s applied to cotton crops grown more than two decades ago suggests that they could enter the food chain. Their presence at depths of 1.2m suggests that they could move into groundwater that may eventually be used for domestic and stock consumption.

Highlights

Posted on 28 May 2012 | 12:52 pm

Decreased anti-Müllerian hormone concentration in follicular fluid of female smokers undergoing artificial reproductive techniques

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Ariel Fuentes, Alex Muñoz, Ricardo Pommer, Begoña Argüello, Andrea Galleguillos, Andrea Torres, Cristian Jesam

Background Several reports indicate that women who smoke have an increased risk of failure to conceive compared with their non-smoker counterparts. Here, we assessed the effect of smoking during the Assisted Reproduction Therapy (ART) on a potential marker of ovarian reserve, anti-müllerian hormone (AMH) in the follicular fluid (FF). Materials and Methods This was a cohort prospective study to assess the association between cigarette smoking and AMH concentrations in FF in fifty-six women undergoing their first ART cycle. Self-reported smoking status over time was also collected through personal interview. The main outcome measured was the association between current smoking and AMH concentrations in FF. Smoking status was assessed by FF cotinine concentrations. Analysis of covariance was performed to test statistical interaction between the main outcome and confounders. Results The mean concentration of AMH in follicular fluid was significantly decreased among smokers (1.02±0.14 vs. 1.74±0.15, P<0.05). No statistical interaction was found between this difference in AMH concentrations and confounders like age and BMI. Thus, our data support the idea that AMH is decreased in active smokers across the fertile age. Conclusions The hypothesis of decreased AMH concentration in follicular fluid in female smokers was confirmed. The mechanisms through which cigarette smoking induces this fall in AMH are unknown and additional research is needed to improve our comprehension of the negative impact of smoking on ART outcomes.

Highlights

Posted on 28 May 2012 | 12:52 pm

Histopathological changes and antioxidant response in brain and kidney of common carp exposed to atrazine and chlorpyrifos

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Houjuan Xing, Shu Li, Zhilei Wang, Xuejiao Gao, Shiwen Xu, Xiaolong Wang

We investigated oxidative stress response and histopathological changes in the brain and kidney of the common carp after a 40-d exposure to CPF and ATR, alone or in combination, and a 20-d recovery. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities and malondialdehyde (MDA) content were measured using standard assays. Our results indicated that exposure to ATR, CPF or a combination of the two for 40d induced significant changes in antioxidant enzyme (SOD, CAT and GSH-Px) activities and MDA content in the brain and kidney of the common carp. Pathological changes included tissue damage that was more severe with increased of exposure dose. To our knowledge, this is the first report to study oxidative stress and histopathological effects caused by subchronic exposure to ATR, CPF and ATR/CPF combination on common carp. The information presented in this study may be helpful to understanding the mechanisms of ATR-, CPF- and ATR/CPF combination-induced oxidative stress in fish.

Highlights

Posted on 28 May 2012 | 12:52 pm

Characterization of dissolved organic matter in the rhizosphere of hyperaccumulator Sedum alfredii and its effect on the mobility of zinc

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Tingqiang Li, Zhenghao Xu, Xuan Han, Xiaoe Yang, Donald L. Sparks

Pot experiments were performed to investigate the characteristics of dissolved organic matter (DOM) in the rhizosphere soil of hyperaccumulating ecotype (HE) and a non-hyperaccumulating ecotype (NHE) of Sedum alfredii and its effects on the mobility of zinc (Zn). DOM was fractionated using XAD resins into six fractions. The acid fraction was the predominant component of DOM in the rhizosphere of S. alfredii, with hydrophilic acid (HiA), hydrophilic base (HiB), and hydrophilic neutral (HiN) in HE-DOM being 1.6, 1.9, and 1.2 times higher respectively, as compared to NHE-DOM. ATR-FTIR results showed that DOM in the rhizosphere of S. alfredii consisted of a mixture of hydroxylated and carboxylic acids, and HE-DOM exhibited more CO, OH, CC and CO functional groups than NHE-DOM. Resin equilibration experiment results indicated that DOM from the rhizosphere of both ecotypes of S. alfredii had the ability to form complexes with Zn, whereas the degree of complexation was significantly higher for HE-DOM (60%) than NHE-DOM (42%). The addition of HE-DOM significantly (P <0.05) increased the solubility of four Zn minerals while NHE-DOM was not as effective at the same concentration. It was concluded that DOM derived from the rhizosphere of hyperaccumulating ecotype of S. alfredii could significantly increase Zn mobility through the formation of soluble DOM–metal complexes, this might be one of the important mechanism by which S. alfredii is involved in activating metal in rhizosphere.

Highlights

Posted on 28 May 2012 | 12:52 pm

Determination of detoxification to Daphnia magna of four pharmaceuticals and seven surfactants by activated sludge

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Göran Dave, Gabriella Herger

Pharmaceuticals are bioactive compounds generally resistant to biodegradation, which can make them problematic when they are released into nature. The use pattern for pharmaceuticals means that they are discharged into water via sewage treatment plants. Also surfactants are discharged through sewage treatment plants, primarily due to their use in detergents and shampoos and other cleaners. In this study the acute toxicity to Daphnia magna of four pharmaceuticals (ciprofloxacin, ibuprofen, paracetamol and zinc pyrithione) and seven surfactants (C8 alkyl glucoside, C6 alkyl glucoside, sodium caprylimidiopropionate, tallow-trimethyl-ammonium chloride, potassium decylphosphate, propylheptanol ethoxylate and alkylmonoethanolamide ethoxylate) was determined. Abiotic (without activated sludge bacteria) and biotic (with activated sludge bacteria) detoxification was also determined. The 24-h EC50s ranged from 2?gL^?1 for the most toxic substance (zinc pyrithione) to 2gL^?1 for the least toxic compound (C6 alkyl glucoside). Detoxification rates determined as the ratio between initial EC50 and EC50 after 1week in water with activated sludge bacteria ranged from 0.4 (paracetamol) to 13 (zinc pyrithione). For most of these chemicals detoxification rate decreased after 1week, but for one (alkylmonoethanolamide ethoxylate) it increased from about 2 to 30 times after 2weeks. Many of these chemicals were “detoxified” also abiotically at about the same rate as biotically. Further studies are needed to determine the degradation products that were precipitated (aggregated) for some of the tested chemicals. Altogether, this study has shown that there are large differences in toxicity among chemicals entering sewage treatment plants, but also that the detoxification of them can differ. Therefore, the detoxification should receive more attention in the hazard and risk assessment of chemicals entering sewage treatment plants.

Highlights

Posted on 28 May 2012 | 12:52 pm

Relative bioavailability to laying hens of indicator polychlorobiphenyls present in soil

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Agnès Fournier, Cyril Feidt, Angélique Travel, Bruno Le Bizec, Anaïs Venisseau, Philippe Marchand, Catherine Jondreville

Transfer of indicator polychlorobiphenyls (PCBs) from soil into hen eggs may occur in hens reared outdoor, which ingest significant amounts of soil. This transfer depends on the bioavailability of the ingested compounds. The impact of soil on the bioavailability of indicator PCBs was assessed by means by a relative bioavailability (RBA) trial, in which their deposition in egg yolk and in abdominal fat, in response to their ingestion through contaminated-soil and through spiked-oil were compared. A sandy soil (709?g indicator PCBskg^?1 dry matter) was collected in the vicinity of a former fire involving treated wood. Twenty-eight laying hens were individually housed and fed one of the seven experimental diets during 14d. The seven experimental diets were an uncontaminated control diet, three diets in which contaminated soil was introduced at levels of 3%, 6% and 9% and three diets in which spiked oil was introduced to achieve similar levels and profile of contaminants. Yolk, abdominal fat and liver were collected at the end of exposure. Indicator PCBs were extracted by ASE (Accelerated Solvent Extraction) and analyzed by GC–HMRS. Within each ingested matrix, the concentration of indicator PCBs in yolk and in abdominal fat linearly increased with the amount of indicator PCB ingested (P <0.001). Except for PCB 28, the slopes of the responses to soil and to oil could not be differentiated (P >0.1). RBA estimates did not differ from 1 for all indicator PCBs except for PCB 28, for which it was 0.58–0.59. Measurements performed on liver confirm these conclusions.

Highlights

Posted on 28 May 2012 | 12:52 pm

Evaluation of trace elements contamination in cloud/fog water at an elevated mountain site in Northern China

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Xiao-huan Liu, Ka-Ming Wai, Yan Wang, Jie Zhou, Peng-hui Li, Jia Guo, Peng-ju Xu, Wen-xing Wang

Totally 117 cloud/fog water samples were collected at the summit of Mt. Tai (1534m a.s.l.)—the highest mountain in the Northern China Plain. The results were investigated by a combination of techniques including back trajectory model, regional air quality and dust storm models, satellite observations and Principal Component Analysis. Elemental concentrations were determined by Inductively Coupled Plasma Mass Spectrometry, with stringent quality control measures. Higher elemental concentrations were found at Mt. Tai compared with those reported by other overseas studies. The larger proportions and higher concentrations of toxic elements such as Pb and As in cloud/fog water compared with those in rainwater at Mt. Tai suggests higher potential hazards of cloud/fog water as a source of contamination in polluted areas to the ecosystem. Peak concentrations of trace elements were frequently observed during the onset of cloud/fog events when liquid water contents of cloud/fog water were usually low and large amount of pollutants were accumulated in the ambient air. Inverse relationship between elemental concentrations and liquid water contents were only found in the samples with high electrical conductivities and liquid water contents lower than 0.3gm^?3. Affected mainly by the emissions of steel industries and mining activities, air masses transported from south/southwest of Mt. Tai were frequently associated with higher elemental concentrations. The element Mn is attributed to play an important role in the acidity of cloud/fog water. The composition of cloud/fog water influenced by an Asian dust storm event was reported, which was seldom found in the literature.

Highlights

Posted on 28 May 2012 | 12:52 pm

Damage to DNA caused by UV-B radiation in the desert cyanobacterium Scytonema javanicum and the effects of exogenous chemicals on the process

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Gaohong Wang, Songqiang Deng, Cheng Li, Yongding Liu, Lanzhou Chen, Chaozhen Hu

Radiation with UV-B increased the damage to DNA in Scytonema javanicum, a desert-dwelling soil microorganism, and the level of damage varied with the intensity of UV-B radiation and duration of exposure. Production of reactive oxygen species (ROS) also increased because of the radiation. Different exogenous chemicals (ascorbate acid, ASC; N-acetylcysteine, NAC; glyphosate, GPS; and 2-methyl-4-chlorophenoxyacetic acid, MCPA-Na) differed in their effect on the extent of DNA damage and ROS production: whereas NAC and ASC protected the DNA from damage and resulted in reduced ROS production, the herbicides (GPS and MCPA-Na) increased the extent of damage, lowered the rate of photosynthesis, and differed in their effect on ROS production. The chemicals probably have different mechanisms to exercise their effects: NAC and ASC probably function as antioxidant agents or as precursors of other antioxidant molecules that protect the DNA and photosynthetic apparatus directly from the ROS produced as a result of UV-B radiation, and GPS and MCPA-Na probably disrupt the normal metabolism in S. javanicum to induce the leaking of ROS into the photosynthetic electron transfer pathway following UV-B radiation, and thereby damage the DNA. Such mechanisms have serious implications for the use of environment-friendly herbicides, which, because they can destroy DNA, may prove harmful to soil microorganisms.

Highlights

Posted on 28 May 2012 | 12:52 pm

Editorial Board

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Posted on 28 May 2012 | 12:52 pm

Blood dioxin biomonitoring to assess local residents’ exposure from a large urban remediation project

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Michael Staff, Vicky Sheppeard, Samanthi Abeywardana, Bradley Forssman, Alison Rutherford, Jochen F. Mueller, Olaf Paepke

Background A total of 265000m³ of dioxin contaminated soil and sediments from past industrial activity was treated on site in an urban setting in Sydney, Australia. To respond to local community concerns about potential dioxin exposure from fugitive emissions a human biomonitoring study was undertaken. Objective To determine whether local residents were exposed to significant amounts of dioxin from the remediation process. Methods: Blood samples were collected from local residents around the site and a representative metropolitan control group. They were pooled within age and sex strata and the change in dioxin concentrations over the remediation period and a summary of the mid point and post remediation dioxin concentrations were compared between groups. Information on dietary intake was collected to look for possible confounding. Results The mean dioxin Toxic Equivalent concentrations (TeQ) decreased among both the local resident and control groups over the remediation period by 1.9 and 2.1pggm^?1 lipid respectively. Modelled blood concentrations adjusting for age and sex did not detect a significant difference between groups for changes in either TeQ or 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8 TCDD). The summary measure approach did however demonstrate that the 2,3,7,8 TCDD concentrations among the local resident group was approximately 0.7pgg^?1 lipid higher compared to the control group post remediation. There were no significant changes in dietary intake sources of dioxin. Conclusion Biomonitoring demonstrated that local residents were not exposed to significant quantities of dioxin. Large scale remediation of dioxin contaminated land can be safely undertaken in an urban setting.

Highlights

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Atmospheric concentrations of PCDD/Fs, dl-PCBs and some pesticides in northern Algeria using passive air sampling

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Yacine Moussaoui, Ludovic Tuduri, Yacine Kerchich, B.Y. Meklati, Gauthier Eppe

Two monitoring campaigns were conducted in northern Algeria to assess the contamination level of pesticides and persistent organic pollutants (POPs) in ambient air. Six pesticides (?- and ?-hexachlorocyclohexane, fenitrothion, malathion, chlorpyrifos and ?-cyhalothrin) were monitored at two different sampling locations during the first campaign. The passive sampling was performed at a semi urban/industrial site but also in a rural area between July to September 2008. The pesticides levels, analyzed by GC/MS/MS, ranged from 16pgm^?3 to 11ngm^?3. The second campaign was carried out from May to November 2009. The polychlorodibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations were evaluated at an urban/industrial and at an industrial site. The PCDD/Fs and dl-PCBs, analyzed by HRGC/HRMS, ranged from 249 to 923fg TEQ m^?3. In addition to passive sampling, active sampling using an isokinetic sampler was also performed at an industrial waste incinerator. The PCDD/Fs and dl-PCBs found was 268pg TEQ m^?3. This paper presents the first measurements of PCDD/Fs, dl-PCBs and pesticides in rural, urban and industrial areas of northern Algeria.

Highlights

Posted on 28 May 2012 | 12:52 pm

Ecotoxicological assessment of metal-polluted urban soils using bioassays with three soil invertebrates

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Lucia Santorufo, Cornelis A.M. Van Gestel, Giulia Maisto

This study aimed at assessing the quality of urban soils by integrating chemical and ecotoxicological approaches. Soils from five sites in downtown Naples, Italy, were sampled and characterized for physical–chemical properties and total and water-extractable metal concentrations. Bioassays with Eisenia andrei, Enchytraeus crypticus and Folsomia candida were performed to assess toxicity of the soils, using survival, reproduction and growth as the endpoints. Metal bioaccumulation in the animals was also measured. The properties and metal concentrations of the soils strongly differed. Metal bioaccumulation was related with total metal concentrations in soil and was highest in E. crypticus, which was more sensitive than E. andrei and F. candida. Responses of the three species to the investigated soils seemed due to both metal contamination and soil properties.

Highlights

Posted on 28 May 2012 | 12:52 pm

Bioconcentration of triclosan, methyl-triclosan, and triclocarban in the plants and sediments of a constructed wetland

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Frederick M. Zarate, Sarah E. Schulwitz, Kevin J. Stevens, Barney J. Venables

Constructed wetlands are a potential method for the removal of two pharmaceutical and personal care products from wastewater effluent. Triclosan (TCS; 5-chloro-2-[2,4-dichlorophenoxy]phenol) and triclocarban (TCC; 3,4,4?-trichlorocarbanillide) are antimicrobial agents added to a variety of consumer products whose accumulation patterns in constructed wetlands are poorly understood. Here, we report the accumulation of TCS, its metabolite methyl-triclosan (MTCS; 5-chloro-2-[2,4-dichlorophenoxy]), and TCC in wetland plant tissues and sediments. Three wetland macrophytes: Typha latifolia, Pontederia cordata, and Sagittaria graminea were sampled from a constructed wetland in Denton, Texas, USA. MTCS concentrations were below the method detection limit (MDL) for all species. TCS root tissue concentrations in T. latifolia were significantly greater than root concentrations in P. cordata (mean±SE in ngg^?1: 40.3±11.3 vs. 15.0±1.9, respectively), while for TCC, shoot tissue concentrations in S. graminea were significantly greater than in T. latifolia (22.8±9.3 vs. 9.0 (MDL), respectively). For both TCS and TCC, T. latifolia root tissue concentrations were significantly greater than shoot concentrations (TCS: 40.3±11.3 vs. 17.2±0.2, TCC: 26.0±3.6 vs. 9.0, (MDL)). TCC concentrations in P. cordata roots were significantly greater than in shoots (34.4±5.3 vs. 15.4±2.8, respectively). TCS concentrations in T. latifolia roots and sediments and TCC concentrations in sediments generally decreased from wetland inflow to outflow. To our knowledge, this is the first study documenting species and tissue specific differences in the accumulation of TCS and TCC in plants from an operational constructed wetland. The species specific differences in bioaccumulation suggest TCS and TCC removal from constructed wetlands could be enhanced through targeted plantings.

Highlights

Posted on 28 May 2012 | 12:52 pm

Phytotoxicity of low-weight carboxylic acids

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Marina Himanen, Petr Prochazka, Kari Hänninen, Aimo Oikari

Presence of low-weight carboxylic acids (LWCAs) can be the reason for phytotoxicity of green manures, treated bio-waste or digestates from biogas production applied to soils. As the phytotoxic concentrations of LWCA are poorly known, this work presents data on six acids (C1 C6: formic, acetic, propionic, butyric, valeric, and caproic). Phytotoxicity was measured in acute (72 or 120h) and subchronic (21 d) assays for seed germination, seedling elongation, and plant growth for garden cress Lepidium sativum and ryegrass Lolium multiflorum. The dose–response relationship was modeled using Weibull model. Results showed a trend that toxicity of LWCA increases with the length of the carbon chain, formic acid (C1) being the least and caproic acid (C6) the most toxic. EC50 values in the acute seed germination of cress ranged between 1.9 and 4.2mM and for ryegrass between 1.8 and 6.4mM. In subchronic assays EC50 values for germination were in a range from 11 to 46mMkg^?1 dm for cress, and from 18 to 127mMkg^?1 dm for ryegrass. EC50 values for early seedling growth of cress based on acute assays ranged from 0.7 to 2.3mM and that of ryegrass from 1.2 to 1.8mM. Range of EC50 values for shoot biomass of cress was between 8 and 40mMkg^?1 dm and of ryegrass between 12 and 93mMkg^?1 dm.

Highlights

Posted on 28 May 2012 | 12:52 pm

Antifeedant, larvicidal and growth inhibitory effects of ononitol monohydrate isolated from Cassia tora L. against Helicoverpa armigera (Hub.) and Spodoptera litura (Fab.) (Lepidoptera: Noctuidae)

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Kathirvelu Baskar, Savarimuthu Ignacimuthu

Ononitol monohydrate isolated from the ethyl acetate extract of Cassia tora L. using column chromatography was evaluated for its antifeedant, larvicidal and growth inhibitory activities against Helicoverpa armigera and Spodoptera litura at different concentrations of 125, 250, 500 and 1000ppm. Leaf disc no-choice method was used for the bioassay. The compound showed significant antifeedant, larvicidal and pupicidal activities against H. armigera and S. litura. The compound also prolonged the larval–pupal duration of the insect at all the tested concentrations. The activities were concentration dependent for both the insects. Ononitol could be used as an agent to prepare botanical new pesticidal formulations.

Highlights

Posted on 28 May 2012 | 12:52 pm

Dissolution kinetics of sub-millimeter Composition B detonation residues: Role of particle size and particle wetting

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Mark E. Fuller, Charles E. Schaefer, Christina Andaya, Volha Lazouskaya, Steve Fallis, Chao Wang, Yan Jin

The dissolution of the 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) from microscale particles (<250?m) of the explosive formulation Composition B was examined and compared to dissolution from macroscopic particles (>0.5mm). The dissolution of explosives from detonation soot was also examined. The measured mass transfer coefficients for the microscale particles were one to two orders of magnitude greater than the macroscopic particles. When normalized to particle surface area, mass transfer coefficients of microscale and macroscale particles were similar, indicating that the bulk dissolution processes were similar throughout the examined size range. However, an inverse relationship was observed between the particle diameter and the RDX:TNT mass transfer rate coefficient ratio for dry-attritted particles, which suggests that RDX may be more readily dissolved (relative to TNT) in microscale particles compared to macroscale particles. Aqueous weathering of larger Composition B residues generated particles that possessed mass transfer coefficients that were on the order of 5- to 20-fold higher than dry-attritted particles of all sizes, even when normalized to particle surface area. These aqueous weathered particles also possessed a fourfold lower absolute zeta-potential than dry-attritted particles, which is indicative that they were less hydrophobic (and hence, more wettable) than dry-attritted particles. The increased wettability of these particles provides a plausible explanation for the observed enhanced dissolution. The wetting history and the processes by which particles are produced (e.g., dry physical attrition vs. aqueous weathering) of Composition B residues should be considered when calculating mass transfer rates for fate and transport modeling.

Highlights

Posted on 28 May 2012 | 12:52 pm

Temporal trends (2005–2009) of PCDD/Fs, PCBs, PBDEs in rice hulls from an e-waste dismantling area after stricter environmental regulations

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Jianjie Fu, Thanh Wang, Pu Wang, Guangbo Qu, Yawei Wang, Qinghua Zhang, Aiqian Zhang, Guibin Jiang

Primitive e-waste dismantling activities have been of increasing concern due to serious environmental and human health problems, and therefore authorities in China have strengthened the regulations on illegal e-waste recycling activities. In this work, we used rice hull as a passive sampler and investigated temporal trends of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) in areas near e-waste recycling sites after the stricter regulations. Furthermore, the distribution patterns and composition profiles of these contaminants were also discussed. The average concentrations of the three groups of persistent organic pollutants (POPs) in rice hulls have markedly decreased during the period of 2005–2009. Specifically, from 12.9 (average value in 2005) to 0.37pg WHO-TEQ/g (dry weight, dw) (in 2009) for PCDD/Fs, 47.6 (2005) to 7.10ngg^?1 dw (2009) for PCBs, and 2.51 (2005) to 0.89ngg^?1, dw (2009) for PBDEs. The significant decrease of combustion markers 2,3,4,7,8-PeCDF, 1,2,3,6,7,8HxCDF and PCB126, and the PCDD/PCDF ratio from 1:9 (2005) to 7:3 (2009) is likely a result of stricter regulations on open combustion activities. This study suggests that stricter control measures, strengthened laws and regulations and more environmental friendly techniques could be effective measures in reducing the release and formation of related POPs in typical e-waste dismantling sites, and these measures could further improve the quality of the environment and health of the local inhabitants.

Highlights

Posted on 28 May 2012 | 12:52 pm

Release of pentachlorophenol from black carbon-inclusive sediments under different environmental conditions

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Liping Lou, Ling Luo, Qiang Yang, Guanghuan Cheng, Bei Xun, Xinhua Xu, Yingxu Chen

To investigate the feasibility of using black carbon (BC) in the control of hydrophobic organic contaminants (HOCs) in sediment, we added BCs from various sources (rice straw charcoal (RC), fly ash (FC) and soot (SC)) to sediment to create different BC-inclusive sediments and studied the release of pentachlorophenol (PCP) in the sediments under different condition. Different pH values had no obvious effect on the release of PCP in BC-inclusive sediment, but solid/liquid ratio, temperature, salinity and dissolved organic matter (DOM) content had significant influences on the release of PCP in all sediments except the RC-inclusive sediment. Adding 2% RC to sediment resulted in a 90% decrease in PCP release, which was a greater decrease than observed with FC- and SC-inclusive sediments. Therefore, from the standpoint of HOC release, the application of RC is feasible for organic pollution control in the water environment.

Graphical abstract

Graphical abstract Highlights

Posted on 28 May 2012 | 12:52 pm

Evidence for in situ production of chlorinated polycyclic aromatic hydrocarbons on tidal flats: Environmental monitoring and laboratory scale experiment

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Kenshi Sankoda, Kei Nomiyama, Takayuki Yonehara, Tomonori Kuribayashi, Ryota Shinohara

This study investigated environmental distributions and production mechanisms of chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs) in the sediments from some tidal flats located in Asia. Cl-PAHs were found in sediments taken from Arao tidal flat, Kikuchigawa River and Shirakawa River. The range of ?Cl-PAHs was from 25.5 to 483pgg^?1 for Kikuchigawa River and Arao tidal flat, respectively. Concentrations of PAHs and Cl-PAHs showed no significant correlations (r =0.134). This result suggests that the origins of these compounds differ. In the identified Cl-PAH isomers, the most abundant Cl-PAH isomer was 9,10-dichloroanthracene (9,10-di-Cl-ANT) in the three sites. In general, concentrations of Cl-ANTs in the coastal environment are about 3–5 orders of magnitude lower than those of anthracene (ANT). However, concentration ratios between Cl-ANTs and ANT (Cl-ANTs/ANT) in the sediments ranged from 4.1% to 24.6%. This result indicated that Cl-PAHs were not generated under industrial processes but the high concentration ratios have resulted from the contribution of photochemical production of Cl-ANTs in the sediments because ANT is known to have high photochemical reactivity. For examining this phenomenon, ANT adsorbed onto glass beads was irradiated with UV under the mimicked field conditions of tidal flats. As a result, it was noticed that, while chlorinated derivatives were negligible in a light-controlled group, production of 2-Cl-ANT, 9-Cl-ANT and 9,10-diCl-ANT on the irradiated surface were found in this study. These results suggest that photochemical reaction of PAHs can be a potential source of the occurrence of Cl-PAHs in the coastal environment.

Highlights

Posted on 28 May 2012 | 12:52 pm

Bottom sediment as a source of organic contaminants in Lake Mead, Nevada, USA

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

David A. Alvarez, Michael R. Rosen, Stephanie D. Perkins, Walter L. Cranor, Vickie L. Schroeder, Tammy L. Jones-Lepp

Treated wastewater effluent from Las Vegas, Nevada and surrounding communities’ flow through Las Vegas Wash (LVW) into the Lake Mead National Recreational Area at Las Vegas Bay (LVB). Lake sediment is a likely sink for many hydrophobic synthetic organic compounds (SOCs); however, partitioning between the sediment and the overlying water could result in the sediment acting as a secondary contaminant source. Locating the chemical plumes may be important to understanding possible chemical stressors to aquatic organisms. Passive sampling devices (SPMDs and POCIS) were suspended in LVB at depths of 3.0, 4.7, and 6.7 (lake bottom) meters in June of 2008 to determine the vertical distribution of SOCs in the water column. A custom sediment probe was used to also bury the samplers in the sediment at depths of 0–10, 10–20, and 20–30cm. The greatest number of detections in samplers buried in the sediment was at the 0–10cm depth. Concentrations of many hydrophobic SOCs were twice as high at the sediment–water interface than in the mid and upper water column. Many SOCs related to wastewater effluents, including fragrances, insect repellants, sun block agents, and phosphate flame retardants, were found at highest concentrations in the middle and upper water column. There was evidence to suggest that the water infiltrated into the sediment had a different chemical composition than the rest of the water column and could be a potential risk exposure to bottom-dwelling aquatic organisms.

Highlights

Posted on 28 May 2012 | 12:52 pm

Quantitative analysis of perfluorinated chemicals in media for in vitro fertilization and related samples

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Yusuke Iwasaki, Emi Terayama, Azusa Kato, Rie Ito, Koichi Saito, Tsunehisa Makino, Hiroyuki Nakazawa

The actual standard in vitro fertilization (IVF) protocol recommends an overnight gamete co-incubation. All of the culture media used for human IVF are supplemented with serum or albumin. In the present study, we determined the concentrations of perfluorinated chemicals (PFCs) in IVF media (IVFM) and related samples by liquid chromatography with tandem mass spectrometry (LC/MS/MS). The results indicated that the concentrations of PFOS and PFOA in the protein source were higher than those in the IVFM samples. Compared with human plasma concentrations of PFCs, PFCs in all of the IVFM samples, such as PFBS, PFHxS and PFOA, were either not detected or present at only trace levels, even when protein source was added. LC/MS/MS could be used to determine PFCs in IVFM samples in future studies of the effects of PFC exposure on intrauterine insemination.

Highlights

Posted on 28 May 2012 | 12:52 pm

Acute contact toxicity test of insecticides (Cipermetrina 25, Lorsban 48E, Thionex 35) on honeybees in the southwestern zone of Uruguay

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Leonidas Carrasco-Letelier, Yamandú Mendoza-Spina, María Belén Branchiccela

Glyphosate-resistant soybean cultivation is expanding rapidly in Uruguay, with its land area having increased by 95 times during the past 10years. Because of the region’s Neotropical conditions, insecticide use is required to ensure adequate soybean productivity. However, in areas shared by soybean crops and beekeepers – such as the southwestern zone of Uruguay (SWZU) – the use of insecticides can increase the risks of honeybee death and honey contamination. Uruguayan commercial and legal guidelines set out practices and field doses designed to prevent acute intoxication with insecticides. However, honeybees in the SWZU are predominantly a polyhybrid subspecies different from that used to set international reference values, and hence they may have a different acute toxicity response, thus rendering such precautions ineffective. The aim of this work was to assess the acute toxicity response of polyhybrid honeybees in the SWZU to cypermethrin (commercial formulation: Cipermetrina 25 Agrin®), chlorpyrifos (commercial formulation: Lorsban 48E®), and endosulfan (commercial formulation: Thionex 35®). Acute toxicity bioassays were conducted to determine the median lethal dose (LD50) of each insecticide for the honeybees. The results indicate that, compared with EU reference values, SWZU honeybees have a higher toxicological sensitivity to chlorpyrifos and endosulfan, and a lower toxicological sensitivity to cypermethrin, based on the commercial formulations tested. However, when these results were adjusted according to their field dose equivalents, only chlorpyrifos emerged as a potential problem for beekeeping, as the maximum recommended field dose of Lorsban 48E® for soybean crops in Uruguay is 23 times the corresponding LD50 for honeybees in the SWZU.

Highlights

Posted on 28 May 2012 | 12:52 pm

Copper toxicity to Lemna minor modelled using humic acid as a surrogate for the plant root

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Paula M.C. Antunes, Marcus L. Scornaienchi, Heather D. Roshon

Humic acids are chemically analogous to plant root cell walls in that their surface sites are principally comprised of carboxylic and phenolic acids which bind both metals and protons. Based on this analogy, we developed a biotic-ligand type of model to predict Cu toxicity to Lemna minor, using particulate humic acid (HApart) of the Windermere Humic Aqueous Model (WHAM), and 7d static-renewal exposures with five surface waters and one nutrient media which varied in DOC (1–10mgL^?1), pH (6.9–8.7), and water hardness (35–236mg equivalent CaCO3 L^?1). Although the range of waters tested resulted in a 36-fold variation in 50% inhibitory concentration (IC50) values, the calculated concentration of Cu bound to HApart using this framework was highly correlated with pooled percent net root elongation (%NRE) (R ² =0.95). Ten and fifty percent IC values based on [Cu-HApart] were additionally within a factor of ±1.5 and ±1.4, respectively, inclusive of 95% confidence limits. This model construct, which defines the free metal ion and the first hydrolysis product (but not metal carbonate complexes) as being bioavailable, provides an alternative means of defining the binding surface in bioavailability models, whereby a heterogeneous mixture of ligands collectively influence root-metal sorption and toxicity.

Highlights

Posted on 28 May 2012 | 12:52 pm

Seasonal fluctuations of DDTs and PCBs in zooplankton and fish of Lake Maggiore (Northern Italy)

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Roberta Bettinetti, Silvia Quadroni, Marina Manca, Roberta Piscia, Pietro Volta, Licia Guzzella, Claudio Roscioli, Silvana Galassi

Concentrations of DDTs and PCBs were determined in the zooplankton and in three different fish species (shad, whitefish and roach) collected seasonally during 2009 and 2010 in three sites in Lake Maggiore, a south-alpine lake that has been contaminated by DDT since 1996. As previously observed in 2008, even during 2009 DDTs concentrations were higher in zooplankton than in fish, probably due to the very unstable situation of the lake still influenced by local inputs. The situation changed in 2010, when all DDT compounds increased in fish to levels much higher than those measured in zooplankton. Biomagnification was statistically demonstrated for pp?DDE in all the three fish species, indicating a probable signal of recovery of the lake. Although with respect to total PCBs we observed that the contamination levels varied across time periods and across fish species, biomagnification was evident from zooplankton to fish both in 2009 and in 2010. As concern individual PCBs, biomagnification from zooplankton to all three fish species was significant for PCB 153 and PCB 138.

Highlights

Posted on 28 May 2012 | 12:52 pm

Formation of artefacts while sampling emissions of PCDD/PCDF from open burning of biomass

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

R.R. Black, C.P. (Mick) Meyer, A. Yates, L. Van Zweiten, J.F. Mueller

Emission factors for PCDD/PCDF determined from open combustion are used to estimate national emission budgets; therefore, it is important to have confidence in their accuracy. It has been suspected that artefacts may form due to the presence of hot metal surfaces of sampling equipment, thus skewing emission factors. In this study, emissions of PCDD/PCDF from open burning of forest biomass over a brick hearth were sampled. Five experiments were carried out using a portable sampler. Experiments were designed where the key variable, sample hood and inlet temperatures were manipulated. Other variables such as fuel origin, type and density were consistent. The measured concentration of PCDD/PCDF in the smoke samples ranged from 0.01?g TEQ (t fuel)^?1 at the lowest maximum hood temperature (185°C) to 15?g TEQ (t fuel)^?1 at the highest maximum hood temperature (598°C). when hood inlet temperatures exceeded 400°C emission factors were significantly elevated and this is attributed to the formation of artefacts that can cause the over estimation of emission factors. The increase in hood temperature also resulted in a change in the PCDD/PCDF congener and homologue profile of the emissions. For example at the lowest temperature (Fire 1) the PCDD/PCDF ratio measured was 50:1, whereas at the highest temperature (Fire 5) this ratio was about 0.53:1. When the sampler hood and inlet temperatures were kept in the normal operating range of <200°C, emission factors were comparable to those observed in many previous studies in Australia with emissions dominated by PCDD.

Highlights

Posted on 28 May 2012 | 12:52 pm

Biodegradation and detoxification of olive mill wastewater by selected strains of the mushroom genera Ganoderma and Pleurotus

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Spyridon Ntougias, Petr Baldrian, Constantinos Ehaliotis, Frantisek Nerud, Theodoros Antoniou, V?ra Merhautová, Georgios I. Zervakis

Thirty-nine white-rot fungi belonging to nine species of Agaricomycotina (Basidiomycota) were initially screened for their ability to decrease olive-mill wastewater (OMW) phenolics. Four strains of Ganoderma australe, Ganoderma carnosum, Pleurotus eryngii and Pleurotus ostreatus, were selected and further examined for key-aspects of the OMW biodegradation process. Fungal growth in OMW-containing batch cultures resulted in significant decolorization (by 40–46% and 60–65% for Ganoderma and Pleurotus spp. respectively) and reduction of phenolics (by 64–67% and 74–81% for Ganoderma and Pleurotus spp. respectively). COD decrease was less pronounced (12–29%). Cress-seeds germination increased by 30–40% when OMW was treated by Pleurotus strains. Toxicity expressed as inhibition of Aliivibrio fischeri luminescence was reduced in fungal-treated OMW samples by approximately 5–15times compared to the control. As regards the pertinent enzyme activities, laccase and Mn-independent peroxidase were detected for Ganoderma spp. during the entire incubation period. In contrast, Pleurotus spp. did not exhibit any enzyme activities at early growth stages; instead, high laccase (five times greater than those of Ganoderma spp.) and Mn peroxidases activities were determined at the end of treatment. OMW decolorization by Ganoderma strains was strongly correlated to the reduction of phenolics, whereas P. eryngii laccase activity was correlated with the effluent’s decolorization.

Highlights

Posted on 28 May 2012 | 12:52 pm

Effects of a catalytic converter on PCDD/F, chlorophenol and PAH emissions in residential wood combustion

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

T. Kaivosoja, A. Virén, J. Tissari, J. Ruuskanen, J. Tarhanen, O. Sippula, J. Jokiniemi

Catalytic converters can be used to decrease carbon monoxide, organic compounds and soot from small-scale wood-fired appliances. The reduction is based on the oxidation of gaseous and particulate pollutants promoted by catalytic transition metal surfaces. However, many transition metals have also strong catalytic effect on PCDD/F formation. In this study birch logs were burned in a wood-fired stove (18kW) with and without a catalytic converter with palladium and platinum as catalysts. PCDD/F, chlorophenol and PAH concentrations were analyzed from three phases of combustion (ignition, pyrolysis and burnout) and from the whole combustion cycle. PCDD/F emissions without the catalytic converter were at a level previously measured for wood combustion (0.15–0.74ngNm^?3). PAH emissions without the catalytic converter were high (47–85mgNm^?3) which is typical for batch combustion of wood logs. Total PAH concentrations were lower (on average 0.8-fold), and chlorophenol and PCDD/F levels were substantially higher (4.3-fold and 8.7-fold, respectively) when the catalytic converter was used. Increase in the chlorophenol and PCDD/F concentrations was most likely due to the catalytic effect of the platinum and palladium. Platinum and palladium may catalyze chlorination of PCDD/Fs via the Deacon reaction or an oxidation process. The influence of emissions from wood combustion to human health and the environment is a sum of effects caused by different compounds formed in the combustion. Therefore, the usage of platinum and palladium based catalytic converters to reduce emissions from residential wood combustion should be critically evaluated before wide-range utilization of the technology.

Highlights

Posted on 28 May 2012 | 12:52 pm

Binary mixtures of azinphos-methyl oxon and chlorpyrifos oxon produce in vitro synergistic cholinesterase inhibition in Planorbarius corneus

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Luis Claudio Cacciatore, Gisela Kristoff, Noemí R. Verrengia Guerrero, Adriana C. Cochón

In this study, the cholinesterase (ChE) and carboxylesterase (CES) activities present in whole organism homogenates from Planorbarius corneus and their in vitro sensitivity to organophosphorous (OP) pesticides were studied. Firstly, a characterization of ChE and CES activities using different substrates and selective inhibitors was performed. Secondly, the effects of azinphos-methyl oxon (AZM-oxon) and chlorpyrifos oxon (CPF-oxon), the active oxygen analogs of the OP insecticides AZM and CPF, on ChE and CES activities were evaluated. Finally, it was analyzed whether binary mixtures of the pesticide oxons cause additive, antagonistic or synergistic ChE inhibition in P. corneus homogenates. The results showed that the extracts of P. corneus preferentially hydrolyzed acetylthiocholine (AcSCh) over propionylthiocholine (PrSCh) and butyrylthiocholine (BuSCh). Besides, AcSCh hydrolyzing activity was inhibited by low concentrations of BW284c51, a selective inhibitor of AChE activity, and also by high concentrations of substrate. These facts suggest the presence of a typical AChE activity in this species. However, the different dose–response curves observed with BW284c51 when using PrSCh or BuSCh instead of AcSCh suggest the presence of at least another ChE activity. This would probably correspond to an atypical BuChE. Regarding CES activity, the highest specific activity was obtained when using 2-naphthyl acetate (2-NA), followed by 1-naphthyl acetate (1-NA); p-nitrophenyl acetate (p-NPA), and p-nitrophenyl butyrate (p-NPB). The comparison of the IC50 values revealed that, regardless of the substrate used, CES activity was approximately one order of magnitude more sensitive to AZM-oxon than ChE activity. Although ChE activity was very sensitive to CPF-oxon, CES activity measured with 1-NA, 2-NA, and p-NPA was poorly inhibited by this pesticide. In contrast, CES activity measured with p-NPB was equally sensitive to CPF-oxon than ChE activity. Several specific binary combinations of AZM-oxon and CPF-oxon caused a synergistic effect on the ChE inhibition in P. corneus homogenates. The degree of synergism tended to increase as the ratio of AZM-oxon to CPF-oxon decreased. These results suggest that synergism is likely to occur in P. corneus snails exposed in vivo to binary mixtures of the OPs AZM and CPF.

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Posted on 28 May 2012 | 12:52 pm

Environmental release of dioxins from reservoir sources during beach nourishment programs

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Yves Tondeur, Bryan Vining, Kimberly Mace, William Mills, Jerry Hart

In late 1990s, USEPA/FDA made an important connection regarding the presence of elevated levels of dioxins (e.g., 1500ngkg^?1 TEQ) in ball clays mined in Mississippi (USA) from a geological deposit dated to ?40million years (Mississippi Embayment) that stretches over several states (northern part of Mississippi to Kentucky) and levels of dioxins in selected animal food sources. Following a recent beach nourishment program along the mid-Atlantic coast of the US, a number of dark gray, blue tinted nuggets of varying sizes were found on beach strands and near the shoreline. Using the presence of these balls of clay (shape, color, and knowledge regarding their use in pottery) on the beach, together with our direct experience analyzing ball clays for dioxins, we made a possible association between these clays and elevated dioxins. Concerns regarding the potential of nourishment programs to cause severe damage to our beaches drove us to test the dioxin content of nourishment exposed clays. A number of the nuggets, along with freshly dredged and deposited sand (collected the morning after nourishment) with the same coloration, and others (sun-bleached), collected approximately 2weeks after the completion of the nourishment efforts, were analyzed for the presence of PCDD/Fs, PCBs, and selected semi-volatile chlorinated organics. The clay PCDD/F WHO2005-TEQs (dry weight; ND=DL; EMPC=EMPC) ranged from 0.41 to 5.78ngkg^?1 with an average of 2.64ngkg^?1, whereas the sand sample’s TEQs ranged from 0.18 to 0.31ngkg^?1 PCDD/F WHO-2005, with an average of 0.22ngkg^?1. The average total tetra- through octachlorinated dibenzo-p-dioxin concentration was 2700ngkg^?1 (with a maximum of 5800ngkg^?1) for the clays and 8.5ngkg^?1 (with a maximum of 16.8ngkg^?1) for the sand samples. The congener 2,3,7,8-TCDD (TEF=1) was detected in half of the clay samples (0.11–0.77ngkg^?1). All of the clay and sand samples displayed an unambiguous and dominating 1,4,6,9-chlorination pattern across homolog groups. No other chlorinated aromatics were detected above background levels. The observations, along with the absence or an extremely low level of polychlorinated dibenzofurans, together with the mineralogical analysis, supports the conclusion that off-shore dredging activities are reaching reservoir sources containing dioxin-tainted, smectic/kaolinite clay minerals. Subsequent beach erosion provides additional environmental releases over time, as buried balls of clay from previous nourishment efforts become exposed.

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Posted on 28 May 2012 | 12:52 pm

Photolysis of flumequine: Identification of the major phototransformation products and toxicity measures

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Carla Sirtori, Ana Zapata, Wolfgang Gernjak, Sixto Malato, Ana Agüera

Direct photolysis of flumequine (FLU, 20mgL^?1) in different types of water (demineralised water (DW) and synthetic seawater (SW)), was conducted in a Suntest CPS+solar simulator to evaluate its persistence and toxicity, and to identify the major phototransformation products (PTPs) generated during photolysis in DW. It was observed that FLU is susceptible to transformation when subjected to direct solar radiation. The composition of the water affects the FLU degradation kinetics, which is slower in SW. Photolytic transformation products generated during direct photolysis were identified by liquid chromatography–time of flight–mass spectrometry (LC–TOF–MS). Fourteen PTPs generated in DW were identified. The transformation of FLU begins with the opening of the heterocyclic ring by oxidation of the double bond. Loss of the fluorine atom and the hydroxylation of the aromatic ring also appear as the majority, especially in the early stages. Comparative acute toxicity evaluation by Vibrio fischeri and Daphnia magna bioassays was performed for the first and last irradiated solutions in both matrices studied. These bioassays demonstrated that in the SW matrix, the most persistent PTPs are highly toxic to D. magna but less so to V. fischeri.

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Posted on 28 May 2012 | 12:52 pm

Mechanochemistry of ibuprofen pharmaceutical

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Salvatore Andini, Adele Bolognese, Domenico Formisano, Michele Manfra, Fabio Montagnaro, Luciano Santoro

In this paper mechanochemistry has been studied in view of possible application to detoxification of expired pharmaceuticals. The experiments have been carried out with a commercial medication containing ibuprofen ((RS)-2-(4-(2-methylpropyl)phenyl)propanoic acid) which has been submitted to prolonged milling up to 40h. When Al(OH)3 is used as co-reagent, the first degradation step induced by the mechanochemical treatment is an acid-base reaction with the ibuprofen carboxylic acid group. The subsequent degradation follows a complex pathway leading to 1-(4-isobutylphenyl)ethanone, 1-isobutyl-4-vinylbenzene and 2-(4-(3-methylbutan-2-yl)phenyl)propan-1-ol after 10h milling and, in addition, 1-(4-acetylphenyl)-2-methylpropan-1-one, 1-(4-(1-hydroxy-2-methylpropyl)phenyl)ethanone and 1-(4-(2-hydroxy-2-methylpropyl)phenyl)ethanone after 40h milling. The degradation reaction path and products have been identified by means of FT-IR spectroscopy, thin layer chromatography, NMR spectroscopy, mass spectroscopy and elemental analysis. The observed ibuprofen decarboxylation makes the drug simultaneously lose both its pharmaceutical activity and toxicity.

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Posted on 28 May 2012 | 12:52 pm

Formation of dioxins during exposure of pesticide formulations to sunlight

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Eva Holt, Roland Weber, Gavin Stevenson, Caroline Gaus

Chlorinated pesticides can contain impurities of dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and their precursors, as a result of various manufacturing processes and conditions. As precursor formation of PCDD/Fs can also be mediated by ultraviolet light (UV), this study investigated whether PCDD/Fs are formed when currently used pesticides are exposed to natural sunlight. Formulations containing pentachloronitrobenzene (PCNB; n =2) and 2,4-dichlorophenoxyacetic acid (2,4-D; n =1) were exposed to sunlight in quartz tubes, and the concentration of 93 PCDD/F congeners were monitored over time. Considerable formation of PCDD/Fs was observed in both PCNB formulations (by up to 5600%, to a maximum concentration of 57000?g?PCDD/Fkg^?1) as well as the 2,4-D formulation (by 3000%, to 140?g?PCDD/Fkg^?1). TEQ also increased by up to 980%, to a maximum concentration of 28?gkg^?1 in PCNB, but did not change in the 2,4-D formulation. Assuming similar yields as observed in the present study as a worst case scenario the use of PCNB in Australia may result in the formation of 155gTEQ annum^?1, contributed primarily by OCDD formation. This warrants detailed evaluations on the contemporary release of PCDD/Fs to the environment after the use of pesticides. Changes in congener profiles (including the ratio of PCDDs to PCDFs (DF ratio)) suggest that pesticide sources of PCDD/Fs after sunlight exposure may not be recognized based on matching source fingerprints established from manufacturing impurities. These changes also provide preliminary insights into the possible formation routes and types of precursors involved.

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Posted on 28 May 2012 | 12:52 pm

Nitrate-induced photodegradation of atenolol in aqueous solution: Kinetics, toxicity and degradation pathways

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 5

Yuefei Ji, Chao Zeng, Corinne Ferronato, Jean-Marc Chovelon, Xi Yang

The extensive utilization of ?-blockers worldwide led to frequent detection in natural water. In this study the photolysis behavior of atenolol (ATL) and toxicity of its photodegradation products were investigated in the presence of nitrate ions. The results showed that ATL photodegradation followed pseudo-first-order kinetics upon simulated solar irradiation. The photodegradation was found to be dependent on nitrate concentration and increasing the nitrate from 0.5mML^?1 to 10mML^?1 led to the enhancement of rate constant from 0.00101min^?1 to 0.00716min^?1. Hydroxyl radical was determined to play a key role in the photolysis process by using isopropanol as molecular probe. Increasing the solution pH from 4.8 to 10.4, the photodegradation rate slightly decreased from 0.00246min^?1 to 0.00195min^?1, probably due to pH-dependent effect of nitrate-induced OH formation. Bicarbonate decreased the photodegradation of ATL in the presence of nitrate ions mainly through pH effect, while humic substance inhibited the photodegradation via both attenuating light and competing radicals. Upon irradiation for 240min, only 10% reduction of total organic carbon (TOC) can be achieved in spite of 72% transformation rate of ATL, implying a majority of ATL transformed into intermediate products rather than complete mineralization. The main photoproducts of ATL were identified by using solid phase extraction–liquid chromatography–mass spectrometry (SPE–LC–MS) techniques and possible nitrate-induced photodegradation pathways were proposed. The toxicity of the phototransformation products was evaluated using aquatic species Daphnia magna, and the results revealed that photodegradation was an effective mechanism for ATL toxicity reduction in natural waters.

Highlights

Posted on 28 May 2012 | 12:52 pm

Tolerance of lead by the fruiting body of Oudemansiella radicata

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 4

Weiwei Zhang, Yuanjia Hu, Yanru Cao, Fengguang Huang, Heng Xu

This study focused on the tolerance responses of the fruiting body of Oudemansiella radicata towards different concentrations of lead (250–1000mgkg^?1) for 2–6d. To know about the lead tolerance and detoxification strategy, the lead content, thiol content and the activities of antioxidant enzymes were investigated. The maximum level for the lead concentration in O. radicata was recorded in the 6d sample in each treatment, and for thiols, it was recorded in the 500mgkg^?1 Pb/2d sample, while for superoxide dismutases (SOD) and catalases (CAT) activities, it was reached at 1000mgkg^?1 Pb after 2d in the stipe and cap, respectively. Peroxidases (POD) activities showed a more complex trend and glutathione reductases (GR) reached the maximum at 500mgkg^?1 Pb after 2d in the stipe. Overall, the results showed that low concentration lead stimulated the fruiting body of O. radicata to produce the thiols and activate the antioxidant enzymes after 2d/4d, while high concentration Pb resulted in the decline/decrease of the thiols and the activities of antioxidant enzymes after 4d/6d. Benefiting from the metal accumulation, detoxification potential and the short lifetime, mushroom have the potential for bioaccumulation of heavy metal in polluted farmland.

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Posted on 28 May 2012 | 12:52 pm

Comparison of organohalogen compounds in a white-tailed sea eagle egg laid in 1941 with five eggs from 1996 to 2001

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Ulrika Nordlöf, Björn Helander, Ulla Eriksson, Yngve Zebühr, Lillemor Asplund

Eggs laid by white-tailed sea eagles (Haliaeetus albicilla), one in 1941 and five eggs between 1996 and 2001, all from the same geographical region of the Baltic Sea, were screened for organohalogen substances. The 1941 egg contained hexachlorobenzene (HCB), but did not contain either of the pesticides hexachlorocyclohexane (HCH) or p,p?-DDT, nor any metabolites of the latter. In contrast, the more recent eggs (REs) contained all of these compounds. Of the seven polychlorinated biphenyls (PCBs) analyzed (CB28, ?52, ?101, ?118, ?138/?163, ?153 and 180), only the more highly chlorinated congeners were detected in the 1941 sample, with CB153 followed by CB180 showing the highest concentrations. All eggs demonstrated the same congener pattern with respect to the more highly chlorinated PCBs, but concentrations were approximately 70–230 times higher in the REs. All of the polychlorinated-p-dioxin and dibenzofuran (PCDD/Fs) congeners analyzed were detected in the eggs, with the dominant congener being 2,3,4,7,8-PeCDF (1250pg/gl.w. in 1941 and 1540pg/gl.w. (GM) for the REs, respectively). None of the other congeners exceeded 400pg/gl.w., and the concentrations of 2,3,7,8-TCDD, 2,3,7,8-TCDF and 1,2,3,7,8-PeCDF were all lower in the REs. None of five congeners of polybrominated diphenyl ethers (PBDEs) found in the REs was detected in the egg from 1941. The three methoxylated brominated diphenyl ethers (MeO-BDEs) analyzed were found at similar levels and with a similar congener pattern in REs as in the egg from 1941. In conclusion, this study has shown the absence of DDE and PBDE and the presence of HCB and PCBs in a white-tailed sea eagle egg laid in 1941, and a strong increase of PCBs, DDE and PBDE in white-tailed sea eagle eggs from the same area in 1996–2001. The MeO-BDEs were found in similar concentrations in the analyzed eggs. The 1941 sample shows substantial concentrations of PCDD/Fs, noteworthy in the same magnitude as in the recent samples, illustrating the historical and recent exposure of these compounds.

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Posted on 28 May 2012 | 12:52 pm

Formation of PCDD/Fs from oxidation of 2-monochlorophenol over an Fe2O3/silica surface

Publication year: 2012
Source:Chemosphere, Volume 88, Issue 3

Shadrack Nganai, Slawo Lomnicki, Barry Dellinger

The role of iron in surface-mediated formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from 2-chlorophenol (2-MCP) was investigated over the temperature range of 200–550°C under oxidative conditions. In order to compare and contrast with previous work on copper and ferric oxide-mediated pyrolysis of 2-MCP, identical reaction conditions were maintained (50ppm 2-MCP, model fly-ash particles containing 5% Fe2O3 on silica). Observed products included dibenzo-p-dioxin (DD), 1-monochlorodibenzo-p-dioxin (1-MCDD), dibenzofuran (DF), 4,6-dichlorodibenzofuran (4,6-DCDF), 2,4- and 2,6-dichlorophenol, 2,4,6-trichlorophenol, quinone, catechol, chloro-o-quinone, chlorocatechol and polychlorinated benzenes. Yields of DD and 1-MCDD were 2 and 5 times higher than under pyolysis conditions, respectively. Although 4,6-DCDF was the major PCDD/F product formed with a yield that was 2.5× greater than under pyrolysis, the yield of non-chlorinated DF, which was the dominant PCDD/F product under pyrolysis, decreased by a factor of 3. Furthermore, the ?2× higher yield of PCDDs under oxidative conditions resulted in a PCDD to PCDF ratio of 0.75 compared to a relatively low ratio of 0.39 previously observed under pyrolytic conditions.

Highlights

Posted on 28 May 2012 | 12:52 pm